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   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 "ext4_i.h"
  24
  25 /*
  26  * The fourth extended filesystem constants/structures
  27  */
  28
  29 /*
  30  * Define EXT4FS_DEBUG to produce debug messages
  31  */
  32 #undef EXT4FS_DEBUG
  33
  34 /*
  35  * Define EXT4_RESERVATION to reserve data blocks for expanding files
  36  */
  37 #define EXT4_DEFAULT_RESERVE_BLOCKS     8
  38 /*max window size: 1024(direct blocks) + 3([t,d]indirect blocks) */
  39 #define EXT4_MAX_RESERVE_BLOCKS         1027
  40 #define EXT4_RESERVE_WINDOW_NOT_ALLOCATED 0
  41
  42 /*
  43  * Debug code
  44  */
  45 #ifdef EXT4FS_DEBUG
  46 #define ext4_debug(f, a...)                                             \
  47         do {                                                            \
  48                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
  49                         __FILE__, __LINE__, __func__);                  \
  50                 printk(KERN_DEBUG f, ## a);                             \
  51         } while (0)
  52 #else
  53 #define ext4_debug(f, a...)     do {} while (0)
  54 #endif
  55
  56 #define EXT4_MULTIBLOCK_ALLOCATOR       1
  57
  58 /* prefer goal again. length */
  59 #define EXT4_MB_HINT_MERGE              1
  60 /* blocks already reserved */
  61 #define EXT4_MB_HINT_RESERVED           2
  62 /* metadata is being allocated */
  63 #define EXT4_MB_HINT_METADATA           4
  64 /* first blocks in the file */
  65 #define EXT4_MB_HINT_FIRST              8
  66 /* search for the best chunk */
  67 #define EXT4_MB_HINT_BEST               16
  68 /* data is being allocated */
  69 #define EXT4_MB_HINT_DATA               32
  70 /* don't preallocate (for tails) */
  71 #define EXT4_MB_HINT_NOPREALLOC         64
  72 /* allocate for locality group */
  73 #define EXT4_MB_HINT_GROUP_ALLOC        128
  74 /* allocate goal blocks or none */
  75 #define EXT4_MB_HINT_GOAL_ONLY          256
  76 /* goal is meaningful */
  77 #define EXT4_MB_HINT_TRY_GOAL           512
  78 /* blocks already pre-reserved by delayed allocation */
  79 #define EXT4_MB_DELALLOC_RESERVED      1024
  80
  81
  82 struct ext4_allocation_request {
  83         /* target inode for block we're allocating */
  84         struct inode *inode;
  85         /* logical block in target inode */
  86         ext4_lblk_t logical;
  87         /* phys. target (a hint) */
  88         ext4_fsblk_t goal;
  89         /* the closest logical allocated block to the left */
  90         ext4_lblk_t lleft;
  91         /* phys. block for ^^^ */
  92         ext4_fsblk_t pleft;
  93         /* the closest logical allocated block to the right */
  94         ext4_lblk_t lright;
  95         /* phys. block for ^^^ */
  96         ext4_fsblk_t pright;
  97         /* how many blocks we want to allocate */
  98         unsigned int len;
  99         /* flags. see above EXT4_MB_HINT_* */
 100         unsigned int flags;
 101 };
 102
 103 /*
 104  * Special inodes numbers
 105  */
 106 #define EXT4_BAD_INO             1      /* Bad blocks inode */
 107 #define EXT4_ROOT_INO            2      /* Root inode */
 108 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
 109 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
 110 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
 111 #define EXT4_JOURNAL_INO         8      /* Journal inode */
 112
 113 /* First non-reserved inode for old ext4 filesystems */
 114 #define EXT4_GOOD_OLD_FIRST_INO 11
 115
 116 /*
 117  * Maximal count of links to a file
 118  */
 119 #define EXT4_LINK_MAX           65000
 120
 121 /*
 122  * Macro-instructions used to manage several block sizes
 123  */
 124 #define EXT4_MIN_BLOCK_SIZE             1024
 125 #define EXT4_MAX_BLOCK_SIZE             65536
 126 #define EXT4_MIN_BLOCK_LOG_SIZE         10
 127 #ifdef __KERNEL__
 128 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
 129 #else
 130 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 131 #endif
 132 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 133 #ifdef __KERNEL__
 134 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
 135 #else
 136 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
 137 #endif
 138 #ifdef __KERNEL__
 139 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
 140 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
 141 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
 142 #else
 143 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 144                                  EXT4_GOOD_OLD_INODE_SIZE : \
 145                                  (s)->s_inode_size)
 146 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 147                                  EXT4_GOOD_OLD_FIRST_INO : \
 148                                  (s)->s_first_ino)
 149 #endif
 150 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
 151
 152 /*
 153  * Structure of a blocks group descriptor
 154  */
 155 struct ext4_group_desc
 156 {
 157         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
 158         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
 159         __le32  bg_inode_table_lo;      /* Inodes table block */
 160         __le16  bg_free_blocks_count_lo;/* Free blocks count */
 161         __le16  bg_free_inodes_count_lo;/* Free inodes count */
 162         __le16  bg_used_dirs_count_lo;  /* Directories count */
 163         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
 164         __u32   bg_reserved[2];         /* Likely block/inode bitmap checksum */
 165         __le16  bg_itable_unused_lo;    /* Unused inodes count */
 166         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
 167         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
 168         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
 169         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
 170         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
 171         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
 172         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
 173         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 174         __u32   bg_reserved2[3];
 175 };
 176
 177 /*
 178  * Structure of a flex block group info
 179  */
 180
 181 struct flex_groups {
 182         __u32 free_inodes;
 183         __u32 free_blocks;
 184 };
 185
 186 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
 187 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
 188 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
 189
 190 #ifdef __KERNEL__
 191 #include "ext4_sb.h"
 192 #endif
 193 /*
 194  * Macro-instructions used to manage group descriptors
 195  */
 196 #define EXT4_MIN_DESC_SIZE              32
 197 #define EXT4_MIN_DESC_SIZE_64BIT        64
 198 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
 199 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
 200 #ifdef __KERNEL__
 201 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 202 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 203 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 204 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 205 #else
 206 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 207 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 208 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 209 #endif
 210
 211 /*
 212  * Constants relative to the data blocks
 213  */
 214 #define EXT4_NDIR_BLOCKS                12
 215 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 216 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 217 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 218 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 219
 220 /*
 221  * Inode flags
 222  */
 223 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 224 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 225 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 226 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 227 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 228 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 229 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 230 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 231 /* Reserved for compression usage... */
 232 #define EXT4_DIRTY_FL                   0x00000100
 233 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 234 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 235 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
 236 /* End compression flags --- maybe not all used */
 237 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 238 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 239 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 240 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 241 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 242 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 243 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 244 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 245 #define EXT4_EXT_MIGRATE                0x00100000 /* Inode is migrating */
 246 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 247
 248 #define EXT4_FL_USER_VISIBLE            0x000BDFFF /* User visible flags */
 249 #define EXT4_FL_USER_MODIFIABLE         0x000B80FF /* User modifiable flags */
 250
 251 /*
 252  * Inode dynamic state flags
 253  */
 254 #define EXT4_STATE_JDATA                0x00000001 /* journaled data exists */
 255 #define EXT4_STATE_NEW                  0x00000002 /* inode is newly created */
 256 #define EXT4_STATE_XATTR                0x00000004 /* has in-inode xattrs */
 257 #define EXT4_STATE_NO_EXPAND            0x00000008 /* No space for expansion */
 258
 259 /* Used to pass group descriptor data when online resize is done */
 260 struct ext4_new_group_input {
 261         __u32 group;            /* Group number for this data */
 262         __u64 block_bitmap;     /* Absolute block number of block bitmap */
 263         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
 264         __u64 inode_table;      /* Absolute block number of inode table start */
 265         __u32 blocks_count;     /* Total number of blocks in this group */
 266         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 267         __u16 unused;
 268 };
 269
 270 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 271 struct ext4_new_group_data {
 272         __u32 group;
 273         __u64 block_bitmap;
 274         __u64 inode_bitmap;
 275         __u64 inode_table;
 276         __u32 blocks_count;
 277         __u16 reserved_blocks;
 278         __u16 unused;
 279         __u32 free_blocks_count;
 280 };
 281
 282 /*
 283  * Following is used by preallocation code to tell get_blocks() that we
 284  * want uninitialzed extents.
 285  */
 286 #define EXT4_CREATE_UNINITIALIZED_EXT           2
 287
 288 /*
 289  * ioctl commands
 290  */
 291 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
 292 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
 293 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 294 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 295 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 296 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 297 #ifdef CONFIG_JBD2_DEBUG
 298 #define EXT4_IOC_WAIT_FOR_READONLY      _IOR('f', 99, long)
 299 #endif
 300 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 301 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 302 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 303 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
 304 #define EXT4_IOC_MIGRATE                _IO('f', 9)
 305  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 306
 307 /*
 308  * ioctl commands in 32 bit emulation
 309  */
 310 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
 311 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
 312 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 313 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 314 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 315 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 316 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 317 #ifdef CONFIG_JBD2_DEBUG
 318 #define EXT4_IOC32_WAIT_FOR_READONLY    _IOR('f', 99, int)
 319 #endif
 320 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 321 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 322
 323
 324 /*
 325  *  Mount options
 326  */
 327 struct ext4_mount_options {
 328         unsigned long s_mount_opt;
 329         uid_t s_resuid;
 330         gid_t s_resgid;
 331         unsigned long s_commit_interval;
 332         u32 s_min_batch_time, s_max_batch_time;
 333 #ifdef CONFIG_QUOTA
 334         int s_jquota_fmt;
 335         char *s_qf_names[MAXQUOTAS];
 336 #endif
 337 };
 338
 339 /*
 340  * Structure of an inode on the disk
 341  */
 342 struct ext4_inode {
 343         __le16  i_mode;         /* File mode */
 344         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 345         __le32  i_size_lo;      /* Size in bytes */
 346         __le32  i_atime;        /* Access time */
 347         __le32  i_ctime;        /* Inode Change time */
 348         __le32  i_mtime;        /* Modification time */
 349         __le32  i_dtime;        /* Deletion Time */
 350         __le16  i_gid;          /* Low 16 bits of Group Id */
 351         __le16  i_links_count;  /* Links count */
 352         __le32  i_blocks_lo;    /* Blocks count */
 353         __le32  i_flags;        /* File flags */
 354         union {
 355                 struct {
 356                         __le32  l_i_version;
 357                 } linux1;
 358                 struct {
 359                         __u32  h_i_translator;
 360                 } hurd1;
 361                 struct {
 362                         __u32  m_i_reserved1;
 363                 } masix1;
 364         } osd1;                         /* OS dependent 1 */
 365         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 366         __le32  i_generation;   /* File version (for NFS) */
 367         __le32  i_file_acl_lo;  /* File ACL */
 368         __le32  i_size_high;
 369         __le32  i_obso_faddr;   /* Obsoleted fragment address */
 370         union {
 371                 struct {
 372                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
 373                         __le16  l_i_file_acl_high;
 374                         __le16  l_i_uid_high;   /* these 2 fields */
 375                         __le16  l_i_gid_high;   /* were reserved2[0] */
 376                         __u32   l_i_reserved2;
 377                 } linux2;
 378                 struct {
 379                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 380                         __u16   h_i_mode_high;
 381                         __u16   h_i_uid_high;
 382                         __u16   h_i_gid_high;
 383                         __u32   h_i_author;
 384                 } hurd2;
 385                 struct {
 386                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 387                         __le16  m_i_file_acl_high;
 388                         __u32   m_i_reserved2[2];
 389                 } masix2;
 390         } osd2;                         /* OS dependent 2 */
 391         __le16  i_extra_isize;
 392         __le16  i_pad1;
 393         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 394         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 395         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 396         __le32  i_crtime;       /* File Creation time */
 397         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 398         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 399 };
 400
 401
 402 #define EXT4_EPOCH_BITS 2
 403 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 404 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 405
 406 /*
 407  * Extended fields will fit into an inode if the filesystem was formatted
 408  * with large inodes (-I 256 or larger) and there are not currently any EAs
 409  * consuming all of the available space. For new inodes we always reserve
 410  * enough space for the kernel's known extended fields, but for inodes
 411  * created with an old kernel this might not have been the case. None of
 412  * the extended inode fields is critical for correct filesystem operation.
 413  * This macro checks if a certain field fits in the inode. Note that
 414  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 415  */
 416 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 417         ((offsetof(typeof(*ext4_inode), field) +        \
 418           sizeof((ext4_inode)->field))                  \
 419         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 420             (einode)->i_extra_isize))                   \
 421
 422 static inline __le32 ext4_encode_extra_time(struct timespec *time)
 423 {
 424        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 425                            time->tv_sec >> 32 : 0) |
 426                            ((time->tv_nsec << 2) & EXT4_NSEC_MASK));
 427 }
 428
 429 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 430 {
 431        if (sizeof(time->tv_sec) > 4)
 432                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 433                                << 32;
 434        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> 2;
 435 }
 436
 437 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
 438 do {                                                                           \
 439         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
 440         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 441                 (raw_inode)->xtime ## _extra =                                 \
 442                                 ext4_encode_extra_time(&(inode)->xtime);       \
 443 } while (0)
 444
 445 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 446 do {                                                                           \
 447         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 448                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 449         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 450                 (raw_inode)->xtime ## _extra =                                 \
 451                                 ext4_encode_extra_time(&(einode)->xtime);      \
 452 } while (0)
 453
 454 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
 455 do {                                                                           \
 456         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 457         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 458                 ext4_decode_extra_time(&(inode)->xtime,                        \
 459                                        raw_inode->xtime ## _extra);            \
 460 } while (0)
 461
 462 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 463 do {                                                                           \
 464         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 465                 (einode)->xtime.tv_sec =                                       \
 466                         (signed)le32_to_cpu((raw_inode)->xtime);               \
 467         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 468                 ext4_decode_extra_time(&(einode)->xtime,                       \
 469                                        raw_inode->xtime ## _extra);            \
 470 } while (0)
 471
 472 #define i_disk_version osd1.linux1.l_i_version
 473
 474 #if defined(__KERNEL__) || defined(__linux__)
 475 #define i_reserved1     osd1.linux1.l_i_reserved1
 476 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 477 #define i_blocks_high   osd2.linux2.l_i_blocks_high
 478 #define i_uid_low       i_uid
 479 #define i_gid_low       i_gid
 480 #define i_uid_high      osd2.linux2.l_i_uid_high
 481 #define i_gid_high      osd2.linux2.l_i_gid_high
 482 #define i_reserved2     osd2.linux2.l_i_reserved2
 483
 484 #elif defined(__GNU__)
 485
 486 #define i_translator    osd1.hurd1.h_i_translator
 487 #define i_uid_high      osd2.hurd2.h_i_uid_high
 488 #define i_gid_high      osd2.hurd2.h_i_gid_high
 489 #define i_author        osd2.hurd2.h_i_author
 490
 491 #elif defined(__masix__)
 492
 493 #define i_reserved1     osd1.masix1.m_i_reserved1
 494 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 495 #define i_reserved2     osd2.masix2.m_i_reserved2
 496
 497 #endif /* defined(__KERNEL__) || defined(__linux__) */
 498
 499 /*
 500  * File system states
 501  */
 502 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
 503 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
 504 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 505
 506 /*
 507  * Misc. filesystem flags
 508  */
 509 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
 510 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
 511 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
 512
 513 /*
 514  * Mount flags
 515  */
 516 #define EXT4_MOUNT_OLDALLOC             0x00002  /* Don't use the new Orlov allocator */
 517 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
 518 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
 519 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
 520 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
 521 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
 522 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
 523 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
 524 #define EXT4_MOUNT_ABORT                0x00200 /* Fatal error detected */
 525 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
 526 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
 527 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
 528 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
 529 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
 530 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
 531 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
 532 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
 533 #define EXT4_MOUNT_RESERVATION          0x10000 /* Preallocation */
 534 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
 535 #define EXT4_MOUNT_NOBH                 0x40000 /* No bufferheads */
 536 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
 537 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
 538 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
 539 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
 540 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
 541 #define EXT4_MOUNT_I_VERSION            0x2000000 /* i_version support */
 542 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
 543 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
 544
 545 /* Compatibility, for having both ext2_fs.h and ext4_fs.h included at once */
 546 #ifndef _LINUX_EXT2_FS_H
 547 #define clear_opt(o, opt)               o &= ~EXT4_MOUNT_##opt
 548 #define set_opt(o, opt)                 o |= EXT4_MOUNT_##opt
 549 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
 550                                          EXT4_MOUNT_##opt)
 551 #else
 552 #define EXT2_MOUNT_NOLOAD               EXT4_MOUNT_NOLOAD
 553 #define EXT2_MOUNT_ABORT                EXT4_MOUNT_ABORT
 554 #define EXT2_MOUNT_DATA_FLAGS           EXT4_MOUNT_DATA_FLAGS
 555 #endif
 556
 557 #define ext4_set_bit                    ext2_set_bit
 558 #define ext4_set_bit_atomic             ext2_set_bit_atomic
 559 #define ext4_clear_bit                  ext2_clear_bit
 560 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
 561 #define ext4_test_bit                   ext2_test_bit
 562 #define ext4_find_first_zero_bit        ext2_find_first_zero_bit
 563 #define ext4_find_next_zero_bit         ext2_find_next_zero_bit
 564 #define ext4_find_next_bit              ext2_find_next_bit
 565
 566 /*
 567  * Maximal mount counts between two filesystem checks
 568  */
 569 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
 570 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
 571
 572 /*
 573  * Behaviour when detecting errors
 574  */
 575 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
 576 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
 577 #define EXT4_ERRORS_PANIC               3       /* Panic */
 578 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
 579
 580 /*
 581  * Structure of the super block
 582  */
 583 struct ext4_super_block {
 584 /*00*/  __le32  s_inodes_count;         /* Inodes count */
 585         __le32  s_blocks_count_lo;      /* Blocks count */
 586         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
 587         __le32  s_free_blocks_count_lo; /* Free blocks count */
 588 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
 589         __le32  s_first_data_block;     /* First Data Block */
 590         __le32  s_log_block_size;       /* Block size */
 591         __le32  s_obso_log_frag_size;   /* Obsoleted fragment size */
 592 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
 593         __le32  s_obso_frags_per_group; /* Obsoleted fragments per group */
 594         __le32  s_inodes_per_group;     /* # Inodes per group */
 595         __le32  s_mtime;                /* Mount time */
 596 /*30*/  __le32  s_wtime;                /* Write time */
 597         __le16  s_mnt_count;            /* Mount count */
 598         __le16  s_max_mnt_count;        /* Maximal mount count */
 599         __le16  s_magic;                /* Magic signature */
 600         __le16  s_state;                /* File system state */
 601         __le16  s_errors;               /* Behaviour when detecting errors */
 602         __le16  s_minor_rev_level;      /* minor revision level */
 603 /*40*/  __le32  s_lastcheck;            /* time of last check */
 604         __le32  s_checkinterval;        /* max. time between checks */
 605         __le32  s_creator_os;           /* OS */
 606         __le32  s_rev_level;            /* Revision level */
 607 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
 608         __le16  s_def_resgid;           /* Default gid for reserved blocks */
 609         /*
 610          * These fields are for EXT4_DYNAMIC_REV superblocks only.
 611          *
 612          * Note: the difference between the compatible feature set and
 613          * the incompatible feature set is that if there is a bit set
 614          * in the incompatible feature set that the kernel doesn't
 615          * know about, it should refuse to mount the filesystem.
 616          *
 617          * e2fsck's requirements are more strict; if it doesn't know
 618          * about a feature in either the compatible or incompatible
 619          * feature set, it must abort and not try to meddle with
 620          * things it doesn't understand...
 621          */
 622         __le32  s_first_ino;            /* First non-reserved inode */
 623         __le16  s_inode_size;           /* size of inode structure */
 624         __le16  s_block_group_nr;       /* block group # of this superblock */
 625         __le32  s_feature_compat;       /* compatible feature set */
 626 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
 627         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
 628 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
 629 /*78*/  char    s_volume_name[16];      /* volume name */
 630 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
 631 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
 632         /*
 633          * Performance hints.  Directory preallocation should only
 634          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
 635          */
 636         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
 637         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
 638         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
 639         /*
 640          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
 641          */
 642 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
 643 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
 644         __le32  s_journal_dev;          /* device number of journal file */
 645         __le32  s_last_orphan;          /* start of list of inodes to delete */
 646         __le32  s_hash_seed[4];         /* HTREE hash seed */
 647         __u8    s_def_hash_version;     /* Default hash version to use */
 648         __u8    s_reserved_char_pad;
 649         __le16  s_desc_size;            /* size of group descriptor */
 650 /*100*/ __le32  s_default_mount_opts;
 651         __le32  s_first_meta_bg;        /* First metablock block group */
 652         __le32  s_mkfs_time;            /* When the filesystem was created */
 653         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
 654         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
 655 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
 656         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
 657         __le32  s_free_blocks_count_hi; /* Free blocks count */
 658         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
 659         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
 660         __le32  s_flags;                /* Miscellaneous flags */
 661         __le16  s_raid_stride;          /* RAID stride */
 662         __le16  s_mmp_interval;         /* # seconds to wait in MMP checking */
 663         __le64  s_mmp_block;            /* Block for multi-mount protection */
 664         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
 665         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
 666         __u8    s_reserved_char_pad2;
 667         __le16  s_reserved_pad;
 668         __u32   s_reserved[162];        /* Padding to the end of the block */
 669 };
 670
 671 #ifdef __KERNEL__
 672 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
 673 {
 674         return sb->s_fs_info;
 675 }
 676 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
 677 {
 678         return container_of(inode, struct ext4_inode_info, vfs_inode);
 679 }
 680
 681 static inline struct timespec ext4_current_time(struct inode *inode)
 682 {
 683         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
 684                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
 685 }
 686
 687
 688 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
 689 {
 690         return ino == EXT4_ROOT_INO ||
 691                 ino == EXT4_JOURNAL_INO ||
 692                 ino == EXT4_RESIZE_INO ||
 693                 (ino >= EXT4_FIRST_INO(sb) &&
 694                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
 695 }
 696 #else
 697 /* Assume that user mode programs are passing in an ext4fs superblock, not
 698  * a kernel struct super_block.  This will allow us to call the feature-test
 699  * macros from user land. */
 700 #define EXT4_SB(sb)     (sb)
 701 #endif
 702
 703 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
 704
 705 /*
 706  * Codes for operating systems
 707  */
 708 #define EXT4_OS_LINUX           0
 709 #define EXT4_OS_HURD            1
 710 #define EXT4_OS_MASIX           2
 711 #define EXT4_OS_FREEBSD         3
 712 #define EXT4_OS_LITES           4
 713
 714 /*
 715  * Revision levels
 716  */
 717 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
 718 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
 719
 720 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
 721 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
 722
 723 #define EXT4_GOOD_OLD_INODE_SIZE 128
 724
 725 /*
 726  * Feature set definitions
 727  */
 728
 729 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
 730         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
 731 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
 732         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
 733 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
 734         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
 735 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
 736         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
 737 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
 738         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
 739 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
 740         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
 741 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
 742         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
 743 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
 744         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
 745 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
 746         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
 747
 748 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
 749 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
 750 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
 751 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
 752 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
 753 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
 754
 755 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
 756 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
 757 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
 758 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
 759 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
 760 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
 761 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
 762
 763 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
 764 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
 765 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
 766 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
 767 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
 768 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
 769 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
 770 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
 771 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
 772
 773 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
 774 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
 775                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
 776                                          EXT4_FEATURE_INCOMPAT_META_BG| \
 777                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
 778                                          EXT4_FEATURE_INCOMPAT_64BIT| \
 779                                          EXT4_FEATURE_INCOMPAT_FLEX_BG)
 780 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
 781                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
 782                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
 783                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
 784                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
 785                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
 786                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
 787
 788 /*
 789  * Default values for user and/or group using reserved blocks
 790  */
 791 #define EXT4_DEF_RESUID         0
 792 #define EXT4_DEF_RESGID         0
 793
 794 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
 795
 796 /*
 797  * Default mount options
 798  */
 799 #define EXT4_DEFM_DEBUG         0x0001
 800 #define EXT4_DEFM_BSDGROUPS     0x0002
 801 #define EXT4_DEFM_XATTR_USER    0x0004
 802 #define EXT4_DEFM_ACL           0x0008
 803 #define EXT4_DEFM_UID16         0x0010
 804 #define EXT4_DEFM_JMODE         0x0060
 805 #define EXT4_DEFM_JMODE_DATA    0x0020
 806 #define EXT4_DEFM_JMODE_ORDERED 0x0040
 807 #define EXT4_DEFM_JMODE_WBACK   0x0060
 808
 809 /*
 810  * Default journal batch times
 811  */
 812 #define EXT4_DEF_MIN_BATCH_TIME 0
 813 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
 814
 815 /*
 816  * Structure of a directory entry
 817  */
 818 #define EXT4_NAME_LEN 255
 819
 820 struct ext4_dir_entry {
 821         __le32  inode;                  /* Inode number */
 822         __le16  rec_len;                /* Directory entry length */
 823         __le16  name_len;               /* Name length */
 824         char    name[EXT4_NAME_LEN];    /* File name */
 825 };
 826
 827 /*
 828  * The new version of the directory entry.  Since EXT4 structures are
 829  * stored in intel byte order, and the name_len field could never be
 830  * bigger than 255 chars, it's safe to reclaim the extra byte for the
 831  * file_type field.
 832  */
 833 struct ext4_dir_entry_2 {
 834         __le32  inode;                  /* Inode number */
 835         __le16  rec_len;                /* Directory entry length */
 836         __u8    name_len;               /* Name length */
 837         __u8    file_type;
 838         char    name[EXT4_NAME_LEN];    /* File name */
 839 };
 840
 841 /*
 842  * Ext4 directory file types.  Only the low 3 bits are used.  The
 843  * other bits are reserved for now.
 844  */
 845 #define EXT4_FT_UNKNOWN         0
 846 #define EXT4_FT_REG_FILE        1
 847 #define EXT4_FT_DIR             2
 848 #define EXT4_FT_CHRDEV          3
 849 #define EXT4_FT_BLKDEV          4
 850 #define EXT4_FT_FIFO            5
 851 #define EXT4_FT_SOCK            6
 852 #define EXT4_FT_SYMLINK         7
 853
 854 #define EXT4_FT_MAX             8
 855
 856 /*
 857  * EXT4_DIR_PAD defines the directory entries boundaries
 858  *
 859  * NOTE: It must be a multiple of 4
 860  */
 861 #define EXT4_DIR_PAD                    4
 862 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
 863 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
 864                                          ~EXT4_DIR_ROUND)
 865 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
 866
 867 static inline unsigned ext4_rec_len_from_disk(__le16 dlen)
 868 {
 869         unsigned len = le16_to_cpu(dlen);
 870
 871         if (len == EXT4_MAX_REC_LEN || len == 0)
 872                 return 1 << 16;
 873         return len;
 874 }
 875
 876 static inline __le16 ext4_rec_len_to_disk(unsigned len)
 877 {
 878         if (len == (1 << 16))
 879                 return cpu_to_le16(EXT4_MAX_REC_LEN);
 880         else if (len > (1 << 16))
 881                 BUG();
 882         return cpu_to_le16(len);
 883 }
 884
 885 /*
 886  * Hash Tree Directory indexing
 887  * (c) Daniel Phillips, 2001
 888  */
 889
 890 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
 891                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
 892                       (EXT4_I(dir)->i_flags & EXT4_INDEX_FL))
 893 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
 894 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
 895
 896 /* Legal values for the dx_root hash_version field: */
 897
 898 #define DX_HASH_LEGACY          0
 899 #define DX_HASH_HALF_MD4        1
 900 #define DX_HASH_TEA             2
 901 #define DX_HASH_LEGACY_UNSIGNED 3
 902 #define DX_HASH_HALF_MD4_UNSIGNED       4
 903 #define DX_HASH_TEA_UNSIGNED            5
 904
 905 #ifdef __KERNEL__
 906
 907 /* hash info structure used by the directory hash */
 908 struct dx_hash_info
 909 {
 910         u32             hash;
 911         u32             minor_hash;
 912         int             hash_version;
 913         u32             *seed;
 914 };
 915
 916 #define EXT4_HTREE_EOF  0x7fffffff
 917
 918 /*
 919  * Control parameters used by ext4_htree_next_block
 920  */
 921 #define HASH_NB_ALWAYS          1
 922
 923
 924 /*
 925  * Describe an inode's exact location on disk and in memory
 926  */
 927 struct ext4_iloc
 928 {
 929         struct buffer_head *bh;
 930         unsigned long offset;
 931         ext4_group_t block_group;
 932 };
 933
 934 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
 935 {
 936         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
 937 }
 938
 939 /*
 940  * This structure is stuffed into the struct file's private_data field
 941  * for directories.  It is where we put information so that we can do
 942  * readdir operations in hash tree order.
 943  */
 944 struct dir_private_info {
 945         struct rb_root  root;
 946         struct rb_node  *curr_node;
 947         struct fname    *extra_fname;
 948         loff_t          last_pos;
 949         __u32           curr_hash;
 950         __u32           curr_minor_hash;
 951         __u32           next_hash;
 952 };
 953
 954 /* calculate the first block number of the group */
 955 static inline ext4_fsblk_t
 956 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
 957 {
 958         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
 959                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
 960 }
 961
 962 /*
 963  * Special error return code only used by dx_probe() and its callers.
 964  */
 965 #define ERR_BAD_DX_DIR  -75000
 966
 967 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
 968                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
 969
 970 extern struct proc_dir_entry *ext4_proc_root;
 971
 972 #ifdef CONFIG_PROC_FS
 973 extern const struct file_operations ext4_ui_proc_fops;
 974
 975 #define EXT4_PROC_HANDLER(name, var)                                    \
 976 do {                                                                    \
 977         proc = proc_create_data(name, mode, sbi->s_proc,                \
 978                                 &ext4_ui_proc_fops, &sbi->s_##var);     \
 979         if (proc == NULL) {                                             \
 980                 printk(KERN_ERR "EXT4-fs: can't create %s\n", name);    \
 981                 goto err_out;                                           \
 982         }                                                               \
 983 } while (0)
 984 #else
 985 #define EXT4_PROC_HANDLER(name, var)
 986 #endif
 987
 988 /*
 989  * Function prototypes
 990  */
 991
 992 /*
 993  * Ok, these declarations are also in <linux/kernel.h> but none of the
 994  * ext4 source programs needs to include it so they are duplicated here.
 995  */
 996 # define NORET_TYPE     /**/
 997 # define ATTRIB_NORET   __attribute__((noreturn))
 998 # define NORET_AND      noreturn,
 999
1000 /* bitmap.c */
1001 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
1002
1003 /* balloc.c */
1004 extern unsigned int ext4_block_group(struct super_block *sb,
1005                         ext4_fsblk_t blocknr);
1006 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1007                         ext4_fsblk_t blocknr);
1008 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1009 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1010                         ext4_group_t group);
1011 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1012                         ext4_fsblk_t goal, unsigned long *count, int *errp);
1013 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1014 extern int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1015 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1016                         ext4_fsblk_t block, unsigned long count, int metadata);
1017 extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
1018                                 ext4_fsblk_t block, unsigned long count);
1019 extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);
1020 extern void ext4_check_blocks_bitmap(struct super_block *);
1021 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1022                                                     ext4_group_t block_group,
1023                                                     struct buffer_head ** bh);
1024 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1025
1026 /* dir.c */
1027 extern int ext4_check_dir_entry(const char *, struct inode *,
1028                                 struct ext4_dir_entry_2 *,
1029                                 struct buffer_head *, unsigned int);
1030 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1031                                     __u32 minor_hash,
1032                                     struct ext4_dir_entry_2 *dirent);
1033 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1034
1035 /* fsync.c */
1036 extern int ext4_sync_file(struct file *, struct dentry *, int);
1037
1038 /* hash.c */
1039 extern int ext4fs_dirhash(const char *name, int len, struct
1040                           dx_hash_info *hinfo);
1041
1042 /* ialloc.c */
1043 extern struct inode * ext4_new_inode(handle_t *, struct inode *, int);
1044 extern void ext4_free_inode(handle_t *, struct inode *);
1045 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1046 extern unsigned long ext4_count_free_inodes(struct super_block *);
1047 extern unsigned long ext4_count_dirs(struct super_block *);
1048 extern void ext4_check_inodes_bitmap(struct super_block *);
1049
1050 /* mballoc.c */
1051 extern long ext4_mb_stats;
1052 extern long ext4_mb_max_to_scan;
1053 extern int ext4_mb_init(struct super_block *, int);
1054 extern int ext4_mb_release(struct super_block *);
1055 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1056                                 struct ext4_allocation_request *, int *);
1057 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1058 extern void ext4_discard_preallocations(struct inode *);
1059 extern int __init init_ext4_mballoc(void);
1060 extern void exit_ext4_mballoc(void);
1061 extern void ext4_mb_free_blocks(handle_t *, struct inode *,
1062                 unsigned long, unsigned long, int, unsigned long *);
1063 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1064                 ext4_group_t i, struct ext4_group_desc *desc);
1065 extern void ext4_mb_update_group_info(struct ext4_group_info *grp,
1066                 ext4_grpblk_t add);
1067 extern int ext4_mb_get_buddy_cache_lock(struct super_block *, ext4_group_t);
1068 extern void ext4_mb_put_buddy_cache_lock(struct super_block *,
1069                                                 ext4_group_t, int);
1070 /* inode.c */
1071 int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode,
1072                 struct buffer_head *bh, ext4_fsblk_t blocknr);
1073 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1074                                                 ext4_lblk_t, int, int *);
1075 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1076                                                 ext4_lblk_t, int, int *);
1077 int ext4_get_block(struct inode *inode, sector_t iblock,
1078                                 struct buffer_head *bh_result, int create);
1079
1080 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1081 extern int  ext4_write_inode(struct inode *, int);
1082 extern int  ext4_setattr(struct dentry *, struct iattr *);
1083 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1084                                 struct kstat *stat);
1085 extern void ext4_delete_inode(struct inode *);
1086 extern int  ext4_sync_inode(handle_t *, struct inode *);
1087 extern void ext4_dirty_inode(struct inode *);
1088 extern int ext4_change_inode_journal_flag(struct inode *, int);
1089 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1090 extern int ext4_can_truncate(struct inode *inode);
1091 extern void ext4_truncate(struct inode *);
1092 extern void ext4_set_inode_flags(struct inode *);
1093 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1094 extern void ext4_set_aops(struct inode *inode);
1095 extern int ext4_writepage_trans_blocks(struct inode *);
1096 extern int ext4_meta_trans_blocks(struct inode *, int nrblocks, int idxblocks);
1097 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1098 extern int ext4_block_truncate_page(handle_t *handle,
1099                 struct address_space *mapping, loff_t from);
1100 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct page *page);
1101
1102 /* ioctl.c */
1103 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1104 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1105
1106 /* migrate.c */
1107 extern int ext4_ext_migrate(struct inode *);
1108 /* namei.c */
1109 extern int ext4_orphan_add(handle_t *, struct inode *);
1110 extern int ext4_orphan_del(handle_t *, struct inode *);
1111 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1112                                 __u32 start_minor_hash, __u32 *next_hash);
1113
1114 /* resize.c */
1115 extern int ext4_group_add(struct super_block *sb,
1116                                 struct ext4_new_group_data *input);
1117 extern int ext4_group_extend(struct super_block *sb,
1118                                 struct ext4_super_block *es,
1119                                 ext4_fsblk_t n_blocks_count);
1120
1121 /* super.c */
1122 extern void ext4_error(struct super_block *, const char *, const char *, ...)
1123         __attribute__ ((format (printf, 3, 4)));
1124 extern void __ext4_std_error(struct super_block *, const char *, int);
1125 extern void ext4_abort(struct super_block *, const char *, const char *, ...)
1126         __attribute__ ((format (printf, 3, 4)));
1127 extern void ext4_warning(struct super_block *, const char *, const char *, ...)
1128         __attribute__ ((format (printf, 3, 4)));
1129 extern void ext4_grp_locked_error(struct super_block *, ext4_group_t,
1130                                 const char *, const char *, ...)
1131         __attribute__ ((format (printf, 4, 5)));
1132 extern void ext4_update_dynamic_rev(struct super_block *sb);
1133 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1134                                         __u32 compat);
1135 extern int ext4_update_rocompat_feature(handle_t *handle,
1136                                         struct super_block *sb, __u32 rocompat);
1137 extern int ext4_update_incompat_feature(handle_t *handle,
1138                                         struct super_block *sb, __u32 incompat);
1139 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
1140                                       struct ext4_group_desc *bg);
1141 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
1142                                       struct ext4_group_desc *bg);
1143 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
1144                                      struct ext4_group_desc *bg);
1145 extern __u32 ext4_free_blks_count(struct super_block *sb,
1146                                 struct ext4_group_desc *bg);
1147 extern __u32 ext4_free_inodes_count(struct super_block *sb,
1148                                  struct ext4_group_desc *bg);
1149 extern __u32 ext4_used_dirs_count(struct super_block *sb,
1150                                 struct ext4_group_desc *bg);
1151 extern __u32 ext4_itable_unused_count(struct super_block *sb,
1152                                    struct ext4_group_desc *bg);
1153 extern void ext4_block_bitmap_set(struct super_block *sb,
1154                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1155 extern void ext4_inode_bitmap_set(struct super_block *sb,
1156                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1157 extern void ext4_inode_table_set(struct super_block *sb,
1158                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
1159 extern void ext4_free_blks_set(struct super_block *sb,
1160                                struct ext4_group_desc *bg, __u32 count);
1161 extern void ext4_free_inodes_set(struct super_block *sb,
1162                                 struct ext4_group_desc *bg, __u32 count);
1163 extern void ext4_used_dirs_set(struct super_block *sb,
1164                                 struct ext4_group_desc *bg, __u32 count);
1165 extern void ext4_itable_unused_set(struct super_block *sb,
1166                                    struct ext4_group_desc *bg, __u32 count);
1167
1168 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
1169 {
1170         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
1171                 le32_to_cpu(es->s_blocks_count_lo);
1172 }
1173
1174 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
1175 {
1176         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
1177                 le32_to_cpu(es->s_r_blocks_count_lo);
1178 }
1179
1180 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
1181 {
1182         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
1183                 le32_to_cpu(es->s_free_blocks_count_lo);
1184 }
1185
1186 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
1187                                          ext4_fsblk_t blk)
1188 {
1189         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
1190         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
1191 }
1192
1193 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
1194                                               ext4_fsblk_t blk)
1195 {
1196         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
1197         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
1198 }
1199
1200 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
1201                                            ext4_fsblk_t blk)
1202 {
1203         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
1204         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
1205 }
1206
1207 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
1208 {
1209         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
1210                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
1211                         le32_to_cpu(raw_inode->i_size_lo);
1212         else
1213                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
1214 }
1215
1216 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
1217 {
1218         raw_inode->i_size_lo = cpu_to_le32(i_size);
1219         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
1220 }
1221
1222 static inline
1223 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
1224                                             ext4_group_t group)
1225 {
1226          struct ext4_group_info ***grp_info;
1227          long indexv, indexh;
1228          grp_info = EXT4_SB(sb)->s_group_info;
1229          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
1230          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
1231          return grp_info[indexv][indexh];
1232 }
1233
1234
1235 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
1236                                              ext4_group_t block_group)
1237 {
1238         return block_group >> sbi->s_log_groups_per_flex;
1239 }
1240
1241 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
1242 {
1243         return 1 << sbi->s_log_groups_per_flex;
1244 }
1245
1246 #define ext4_std_error(sb, errno)                               \
1247 do {                                                            \
1248         if ((errno))                                            \
1249                 __ext4_std_error((sb), __func__, (errno));      \
1250 } while (0)
1251
1252 #ifdef CONFIG_SMP
1253 /* Each CPU can accumulate percpu_counter_batch blocks in their local
1254  * counters. So we need to make sure we have free blocks more
1255  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
1256  */
1257 #define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
1258 #else
1259 #define EXT4_FREEBLOCKS_WATERMARK 0
1260 #endif
1261
1262 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
1263 {
1264         /*
1265          * XXX: replace with spinlock if seen contended -bzzz
1266          */
1267         down_write(&EXT4_I(inode)->i_data_sem);
1268         if (newsize > EXT4_I(inode)->i_disksize)
1269                 EXT4_I(inode)->i_disksize = newsize;
1270         up_write(&EXT4_I(inode)->i_data_sem);
1271         return ;
1272 }
1273
1274 struct ext4_group_info {
1275         unsigned long   bb_state;
1276         struct rb_root  bb_free_root;
1277         unsigned short  bb_first_free;
1278         unsigned short  bb_free;
1279         unsigned short  bb_fragments;
1280         struct          list_head bb_prealloc_list;
1281 #ifdef DOUBLE_CHECK
1282         void            *bb_bitmap;
1283 #endif
1284         struct rw_semaphore alloc_sem;
1285         unsigned short  bb_counters[];
1286 };
1287
1288 #define EXT4_GROUP_INFO_NEED_INIT_BIT   0
1289 #define EXT4_GROUP_INFO_LOCKED_BIT      1
1290
1291 #define EXT4_MB_GRP_NEED_INIT(grp)      \
1292         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
1293
1294 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
1295 {
1296         struct ext4_group_info *grinfo = ext4_get_group_info(sb, group);
1297
1298         bit_spin_lock(EXT4_GROUP_INFO_LOCKED_BIT, &(grinfo->bb_state));
1299 }
1300
1301 static inline void ext4_unlock_group(struct super_block *sb,
1302                                         ext4_group_t group)
1303 {
1304         struct ext4_group_info *grinfo = ext4_get_group_info(sb, group);
1305
1306         bit_spin_unlock(EXT4_GROUP_INFO_LOCKED_BIT, &(grinfo->bb_state));
1307 }
1308
1309 static inline int ext4_is_group_locked(struct super_block *sb,
1310                                         ext4_group_t group)
1311 {
1312         struct ext4_group_info *grinfo = ext4_get_group_info(sb, group);
1313
1314         return bit_spin_is_locked(EXT4_GROUP_INFO_LOCKED_BIT,
1315                                                 &(grinfo->bb_state));
1316 }
1317
1318 /*
1319  * Inodes and files operations
1320  */
1321
1322 /* dir.c */
1323 extern const struct file_operations ext4_dir_operations;
1324
1325 /* file.c */
1326 extern const struct inode_operations ext4_file_inode_operations;
1327 extern const struct file_operations ext4_file_operations;
1328
1329 /* namei.c */
1330 extern const struct inode_operations ext4_dir_inode_operations;
1331 extern const struct inode_operations ext4_special_inode_operations;
1332
1333 /* symlink.c */
1334 extern const struct inode_operations ext4_symlink_inode_operations;
1335 extern const struct inode_operations ext4_fast_symlink_inode_operations;
1336
1337 /* extents.c */
1338 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
1339 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
1340 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
1341                                        int chunk);
1342 extern int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
1343                                ext4_lblk_t iblock, unsigned int max_blocks,
1344                                struct buffer_head *bh_result,
1345                                int create, int extend_disksize);
1346 extern void ext4_ext_truncate(struct inode *);
1347 extern void ext4_ext_init(struct super_block *);
1348 extern void ext4_ext_release(struct super_block *);
1349 extern long ext4_fallocate(struct inode *inode, int mode, loff_t offset,
1350                           loff_t len);
1351 extern int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode,
1352                         sector_t block, unsigned int max_blocks,
1353                         struct buffer_head *bh, int create,
1354                         int extend_disksize, int flag);
1355 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1356                         __u64 start, __u64 len);
1357
1358 /*
1359  * Add new method to test wether block and inode bitmaps are properly
1360  * initialized. With uninit_bg reading the block from disk is not enough
1361  * to mark the bitmap uptodate. We need to also zero-out the bitmap
1362  */
1363 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
1364
1365 static inline int bitmap_uptodate(struct buffer_head *bh)
1366 {
1367         return (buffer_uptodate(bh) &&
1368                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
1369 }
1370 static inline void set_bitmap_uptodate(struct buffer_head *bh)
1371 {
1372         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
1373 }
1374
1375 #endif  /* __KERNEL__ */
1376
1377 #endif  /* _EXT4_H */