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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 <linux/quota.h>
  24 #include "ext4_i.h"
  25
  26 /*
  27  * The fourth extended filesystem constants/structures
  28  */
  29
  30 /*
  31  * Define EXT4FS_DEBUG to produce debug messages
  32  */
  33 #undef EXT4FS_DEBUG
  34
  35 /*
  36  * Debug code
  37  */
  38 #ifdef EXT4FS_DEBUG
  39 #define ext4_debug(f, a...)                                             \
  40         do {                                                            \
  41                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
  42                         __FILE__, __LINE__, __func__);                  \
  43                 printk(KERN_DEBUG f, ## a);                             \
  44         } while (0)
  45 #else
  46 #define ext4_debug(f, a...)     do {} while (0)
  47 #endif
  48
  49 /* prefer goal again. length */
  50 #define EXT4_MB_HINT_MERGE              1
  51 /* blocks already reserved */
  52 #define EXT4_MB_HINT_RESERVED           2
  53 /* metadata is being allocated */
  54 #define EXT4_MB_HINT_METADATA           4
  55 /* first blocks in the file */
  56 #define EXT4_MB_HINT_FIRST              8
  57 /* search for the best chunk */
  58 #define EXT4_MB_HINT_BEST               16
  59 /* data is being allocated */
  60 #define EXT4_MB_HINT_DATA               32
  61 /* don't preallocate (for tails) */
  62 #define EXT4_MB_HINT_NOPREALLOC         64
  63 /* allocate for locality group */
  64 #define EXT4_MB_HINT_GROUP_ALLOC        128
  65 /* allocate goal blocks or none */
  66 #define EXT4_MB_HINT_GOAL_ONLY          256
  67 /* goal is meaningful */
  68 #define EXT4_MB_HINT_TRY_GOAL           512
  69 /* blocks already pre-reserved by delayed allocation */
  70 #define EXT4_MB_DELALLOC_RESERVED      1024
  71
  72
  73 struct ext4_allocation_request {
  74         /* target inode for block we're allocating */
  75         struct inode *inode;
  76         /* logical block in target inode */
  77         ext4_lblk_t logical;
  78         /* phys. target (a hint) */
  79         ext4_fsblk_t goal;
  80         /* the closest logical allocated block to the left */
  81         ext4_lblk_t lleft;
  82         /* phys. block for ^^^ */
  83         ext4_fsblk_t pleft;
  84         /* the closest logical allocated block to the right */
  85         ext4_lblk_t lright;
  86         /* phys. block for ^^^ */
  87         ext4_fsblk_t pright;
  88         /* how many blocks we want to allocate */
  89         unsigned int len;
  90         /* flags. see above EXT4_MB_HINT_* */
  91         unsigned int flags;
  92 };
  93
  94 /*
  95  * Special inodes numbers
  96  */
  97 #define EXT4_BAD_INO             1      /* Bad blocks inode */
  98 #define EXT4_ROOT_INO            2      /* Root inode */
  99 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
 100 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
 101 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
 102 #define EXT4_JOURNAL_INO         8      /* Journal inode */
 103
 104 /* First non-reserved inode for old ext4 filesystems */
 105 #define EXT4_GOOD_OLD_FIRST_INO 11
 106
 107 /*
 108  * Maximal count of links to a file
 109  */
 110 #define EXT4_LINK_MAX           65000
 111
 112 /*
 113  * Macro-instructions used to manage several block sizes
 114  */
 115 #define EXT4_MIN_BLOCK_SIZE             1024
 116 #define EXT4_MAX_BLOCK_SIZE             65536
 117 #define EXT4_MIN_BLOCK_LOG_SIZE         10
 118 #ifdef __KERNEL__
 119 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
 120 #else
 121 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 122 #endif
 123 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 124 #ifdef __KERNEL__
 125 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
 126 #else
 127 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
 128 #endif
 129 #ifdef __KERNEL__
 130 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
 131 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
 132 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
 133 #else
 134 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 135                                  EXT4_GOOD_OLD_INODE_SIZE : \
 136                                  (s)->s_inode_size)
 137 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 138                                  EXT4_GOOD_OLD_FIRST_INO : \
 139                                  (s)->s_first_ino)
 140 #endif
 141 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
 142
 143 /*
 144  * Structure of a blocks group descriptor
 145  */
 146 struct ext4_group_desc
 147 {
 148         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
 149         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
 150         __le32  bg_inode_table_lo;      /* Inodes table block */
 151         __le16  bg_free_blocks_count_lo;/* Free blocks count */
 152         __le16  bg_free_inodes_count_lo;/* Free inodes count */
 153         __le16  bg_used_dirs_count_lo;  /* Directories count */
 154         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
 155         __u32   bg_reserved[2];         /* Likely block/inode bitmap checksum */
 156         __le16  bg_itable_unused_lo;    /* Unused inodes count */
 157         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
 158         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
 159         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
 160         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
 161         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
 162         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
 163         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
 164         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 165         __u32   bg_reserved2[3];
 166 };
 167
 168 /*
 169  * Structure of a flex block group info
 170  */
 171
 172 struct flex_groups {
 173         __u32 free_inodes;
 174         __u32 free_blocks;
 175 };
 176
 177 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
 178 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
 179 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
 180
 181 #ifdef __KERNEL__
 182 #include "ext4_sb.h"
 183 #endif
 184 /*
 185  * Macro-instructions used to manage group descriptors
 186  */
 187 #define EXT4_MIN_DESC_SIZE              32
 188 #define EXT4_MIN_DESC_SIZE_64BIT        64
 189 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
 190 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
 191 #ifdef __KERNEL__
 192 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 193 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 194 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 195 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 196 #else
 197 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 198 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 199 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 200 #endif
 201
 202 /*
 203  * Constants relative to the data blocks
 204  */
 205 #define EXT4_NDIR_BLOCKS                12
 206 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 207 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 208 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 209 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 210
 211 /*
 212  * Inode flags
 213  */
 214 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 215 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 216 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 217 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 218 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 219 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 220 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 221 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 222 /* Reserved for compression usage... */
 223 #define EXT4_DIRTY_FL                   0x00000100
 224 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 225 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 226 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
 227 /* End compression flags --- maybe not all used */
 228 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 229 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 230 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 231 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 232 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 233 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 234 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 235 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 236 #define EXT4_EXT_MIGRATE                0x00100000 /* Inode is migrating */
 237 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 238
 239 #define EXT4_FL_USER_VISIBLE            0x000BDFFF /* User visible flags */
 240 #define EXT4_FL_USER_MODIFIABLE         0x000B80FF /* User modifiable flags */
 241
 242 /* Flags that should be inherited by new inodes from their parent. */
 243 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 244                            EXT4_SYNC_FL | EXT4_IMMUTABLE_FL | EXT4_APPEND_FL |\
 245                            EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 246                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 247                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
 248
 249 /* Flags that are appropriate for regular files (all but dir-specific ones). */
 250 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
 251
 252 /* Flags that are appropriate for non-directories/regular files. */
 253 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 254
 255 /* Mask out flags that are inappropriate for the given type of inode. */
 256 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 257 {
 258         if (S_ISDIR(mode))
 259                 return flags;
 260         else if (S_ISREG(mode))
 261                 return flags & EXT4_REG_FLMASK;
 262         else
 263                 return flags & EXT4_OTHER_FLMASK;
 264 }
 265
 266 /*
 267  * Inode dynamic state flags
 268  */
 269 #define EXT4_STATE_JDATA                0x00000001 /* journaled data exists */
 270 #define EXT4_STATE_NEW                  0x00000002 /* inode is newly created */
 271 #define EXT4_STATE_XATTR                0x00000004 /* has in-inode xattrs */
 272 #define EXT4_STATE_NO_EXPAND            0x00000008 /* No space for expansion */
 273
 274 /* Used to pass group descriptor data when online resize is done */
 275 struct ext4_new_group_input {
 276         __u32 group;            /* Group number for this data */
 277         __u64 block_bitmap;     /* Absolute block number of block bitmap */
 278         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
 279         __u64 inode_table;      /* Absolute block number of inode table start */
 280         __u32 blocks_count;     /* Total number of blocks in this group */
 281         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 282         __u16 unused;
 283 };
 284
 285 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 286 struct ext4_new_group_data {
 287         __u32 group;
 288         __u64 block_bitmap;
 289         __u64 inode_bitmap;
 290         __u64 inode_table;
 291         __u32 blocks_count;
 292         __u16 reserved_blocks;
 293         __u16 unused;
 294         __u32 free_blocks_count;
 295 };
 296
 297 /*
 298  * Following is used by preallocation code to tell get_blocks() that we
 299  * want uninitialzed extents.
 300  */
 301 #define EXT4_CREATE_UNINITIALIZED_EXT           2
 302
 303 /*
 304  * ioctl commands
 305  */
 306 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
 307 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
 308 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 309 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 310 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 311 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 312 #ifdef CONFIG_JBD2_DEBUG
 313 #define EXT4_IOC_WAIT_FOR_READONLY      _IOR('f', 99, long)
 314 #endif
 315 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 316 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 317 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 318 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
 319 #define EXT4_IOC_MIGRATE                _IO('f', 9)
 320  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 321
 322 /*
 323  * ioctl commands in 32 bit emulation
 324  */
 325 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
 326 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
 327 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 328 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 329 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 330 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 331 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 332 #ifdef CONFIG_JBD2_DEBUG
 333 #define EXT4_IOC32_WAIT_FOR_READONLY    _IOR('f', 99, int)
 334 #endif
 335 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 336 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 337
 338
 339 /*
 340  *  Mount options
 341  */
 342 struct ext4_mount_options {
 343         unsigned long s_mount_opt;
 344         uid_t s_resuid;
 345         gid_t s_resgid;
 346         unsigned long s_commit_interval;
 347         u32 s_min_batch_time, s_max_batch_time;
 348 #ifdef CONFIG_QUOTA
 349         int s_jquota_fmt;
 350         char *s_qf_names[MAXQUOTAS];
 351 #endif
 352 };
 353
 354 /*
 355  * Structure of an inode on the disk
 356  */
 357 struct ext4_inode {
 358         __le16  i_mode;         /* File mode */
 359         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 360         __le32  i_size_lo;      /* Size in bytes */
 361         __le32  i_atime;        /* Access time */
 362         __le32  i_ctime;        /* Inode Change time */
 363         __le32  i_mtime;        /* Modification time */
 364         __le32  i_dtime;        /* Deletion Time */
 365         __le16  i_gid;          /* Low 16 bits of Group Id */
 366         __le16  i_links_count;  /* Links count */
 367         __le32  i_blocks_lo;    /* Blocks count */
 368         __le32  i_flags;        /* File flags */
 369         union {
 370                 struct {
 371                         __le32  l_i_version;
 372                 } linux1;
 373                 struct {
 374                         __u32  h_i_translator;
 375                 } hurd1;
 376                 struct {
 377                         __u32  m_i_reserved1;
 378                 } masix1;
 379         } osd1;                         /* OS dependent 1 */
 380         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 381         __le32  i_generation;   /* File version (for NFS) */
 382         __le32  i_file_acl_lo;  /* File ACL */
 383         __le32  i_size_high;
 384         __le32  i_obso_faddr;   /* Obsoleted fragment address */
 385         union {
 386                 struct {
 387                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
 388                         __le16  l_i_file_acl_high;
 389                         __le16  l_i_uid_high;   /* these 2 fields */
 390                         __le16  l_i_gid_high;   /* were reserved2[0] */
 391                         __u32   l_i_reserved2;
 392                 } linux2;
 393                 struct {
 394                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 395                         __u16   h_i_mode_high;
 396                         __u16   h_i_uid_high;
 397                         __u16   h_i_gid_high;
 398                         __u32   h_i_author;
 399                 } hurd2;
 400                 struct {
 401                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 402                         __le16  m_i_file_acl_high;
 403                         __u32   m_i_reserved2[2];
 404                 } masix2;
 405         } osd2;                         /* OS dependent 2 */
 406         __le16  i_extra_isize;
 407         __le16  i_pad1;
 408         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 409         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 410         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 411         __le32  i_crtime;       /* File Creation time */
 412         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 413         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 414 };
 415
 416
 417 #define EXT4_EPOCH_BITS 2
 418 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 419 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 420
 421 /*
 422  * Extended fields will fit into an inode if the filesystem was formatted
 423  * with large inodes (-I 256 or larger) and there are not currently any EAs
 424  * consuming all of the available space. For new inodes we always reserve
 425  * enough space for the kernel's known extended fields, but for inodes
 426  * created with an old kernel this might not have been the case. None of
 427  * the extended inode fields is critical for correct filesystem operation.
 428  * This macro checks if a certain field fits in the inode. Note that
 429  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 430  */
 431 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 432         ((offsetof(typeof(*ext4_inode), field) +        \
 433           sizeof((ext4_inode)->field))                  \
 434         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 435             (einode)->i_extra_isize))                   \
 436
 437 static inline __le32 ext4_encode_extra_time(struct timespec *time)
 438 {
 439        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 440                            time->tv_sec >> 32 : 0) |
 441                            ((time->tv_nsec << 2) & EXT4_NSEC_MASK));
 442 }
 443
 444 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 445 {
 446        if (sizeof(time->tv_sec) > 4)
 447                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 448                                << 32;
 449        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> 2;
 450 }
 451
 452 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
 453 do {                                                                           \
 454         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
 455         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 456                 (raw_inode)->xtime ## _extra =                                 \
 457                                 ext4_encode_extra_time(&(inode)->xtime);       \
 458 } while (0)
 459
 460 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 461 do {                                                                           \
 462         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 463                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 464         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 465                 (raw_inode)->xtime ## _extra =                                 \
 466                                 ext4_encode_extra_time(&(einode)->xtime);      \
 467 } while (0)
 468
 469 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
 470 do {                                                                           \
 471         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 472         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 473                 ext4_decode_extra_time(&(inode)->xtime,                        \
 474                                        raw_inode->xtime ## _extra);            \
 475 } while (0)
 476
 477 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 478 do {                                                                           \
 479         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 480                 (einode)->xtime.tv_sec =                                       \
 481                         (signed)le32_to_cpu((raw_inode)->xtime);               \
 482         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 483                 ext4_decode_extra_time(&(einode)->xtime,                       \
 484                                        raw_inode->xtime ## _extra);            \
 485 } while (0)
 486
 487 #define i_disk_version osd1.linux1.l_i_version
 488
 489 #if defined(__KERNEL__) || defined(__linux__)
 490 #define i_reserved1     osd1.linux1.l_i_reserved1
 491 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 492 #define i_blocks_high   osd2.linux2.l_i_blocks_high
 493 #define i_uid_low       i_uid
 494 #define i_gid_low       i_gid
 495 #define i_uid_high      osd2.linux2.l_i_uid_high
 496 #define i_gid_high      osd2.linux2.l_i_gid_high
 497 #define i_reserved2     osd2.linux2.l_i_reserved2
 498
 499 #elif defined(__GNU__)
 500
 501 #define i_translator    osd1.hurd1.h_i_translator
 502 #define i_uid_high      osd2.hurd2.h_i_uid_high
 503 #define i_gid_high      osd2.hurd2.h_i_gid_high
 504 #define i_author        osd2.hurd2.h_i_author
 505
 506 #elif defined(__masix__)
 507
 508 #define i_reserved1     osd1.masix1.m_i_reserved1
 509 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 510 #define i_reserved2     osd2.masix2.m_i_reserved2
 511
 512 #endif /* defined(__KERNEL__) || defined(__linux__) */
 513
 514 /*
 515  * File system states
 516  */
 517 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
 518 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
 519 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 520
 521 /*
 522  * Misc. filesystem flags
 523  */
 524 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
 525 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
 526 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
 527
 528 /*
 529  * Mount flags
 530  */
 531 #define EXT4_MOUNT_OLDALLOC             0x00002  /* Don't use the new Orlov allocator */
 532 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
 533 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
 534 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
 535 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
 536 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
 537 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
 538 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
 539 #define EXT4_MOUNT_ABORT                0x00200 /* Fatal error detected */
 540 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
 541 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
 542 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
 543 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
 544 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
 545 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
 546 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
 547 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
 548 #define EXT4_MOUNT_RESERVATION          0x10000 /* Preallocation */
 549 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
 550 #define EXT4_MOUNT_NOBH                 0x40000 /* No bufferheads */
 551 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
 552 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
 553 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
 554 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
 555 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
 556 #define EXT4_MOUNT_I_VERSION            0x2000000 /* i_version support */
 557 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
 558 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
 559
 560 /* Compatibility, for having both ext2_fs.h and ext4_fs.h included at once */
 561 #ifndef _LINUX_EXT2_FS_H
 562 #define clear_opt(o, opt)               o &= ~EXT4_MOUNT_##opt
 563 #define set_opt(o, opt)                 o |= EXT4_MOUNT_##opt
 564 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
 565                                          EXT4_MOUNT_##opt)
 566 #else
 567 #define EXT2_MOUNT_NOLOAD               EXT4_MOUNT_NOLOAD
 568 #define EXT2_MOUNT_ABORT                EXT4_MOUNT_ABORT
 569 #define EXT2_MOUNT_DATA_FLAGS           EXT4_MOUNT_DATA_FLAGS
 570 #endif
 571
 572 #define ext4_set_bit                    ext2_set_bit
 573 #define ext4_set_bit_atomic             ext2_set_bit_atomic
 574 #define ext4_clear_bit                  ext2_clear_bit
 575 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
 576 #define ext4_test_bit                   ext2_test_bit
 577 #define ext4_find_first_zero_bit        ext2_find_first_zero_bit
 578 #define ext4_find_next_zero_bit         ext2_find_next_zero_bit
 579 #define ext4_find_next_bit              ext2_find_next_bit
 580
 581 /*
 582  * Maximal mount counts between two filesystem checks
 583  */
 584 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
 585 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
 586
 587 /*
 588  * Behaviour when detecting errors
 589  */
 590 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
 591 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
 592 #define EXT4_ERRORS_PANIC               3       /* Panic */
 593 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
 594
 595 /*
 596  * Structure of the super block
 597  */
 598 struct ext4_super_block {
 599 /*00*/  __le32  s_inodes_count;         /* Inodes count */
 600         __le32  s_blocks_count_lo;      /* Blocks count */
 601         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
 602         __le32  s_free_blocks_count_lo; /* Free blocks count */
 603 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
 604         __le32  s_first_data_block;     /* First Data Block */
 605         __le32  s_log_block_size;       /* Block size */
 606         __le32  s_obso_log_frag_size;   /* Obsoleted fragment size */
 607 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
 608         __le32  s_obso_frags_per_group; /* Obsoleted fragments per group */
 609         __le32  s_inodes_per_group;     /* # Inodes per group */
 610         __le32  s_mtime;                /* Mount time */
 611 /*30*/  __le32  s_wtime;                /* Write time */
 612         __le16  s_mnt_count;            /* Mount count */
 613         __le16  s_max_mnt_count;        /* Maximal mount count */
 614         __le16  s_magic;                /* Magic signature */
 615         __le16  s_state;                /* File system state */
 616         __le16  s_errors;               /* Behaviour when detecting errors */
 617         __le16  s_minor_rev_level;      /* minor revision level */
 618 /*40*/  __le32  s_lastcheck;            /* time of last check */
 619         __le32  s_checkinterval;        /* max. time between checks */
 620         __le32  s_creator_os;           /* OS */
 621         __le32  s_rev_level;            /* Revision level */
 622 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
 623         __le16  s_def_resgid;           /* Default gid for reserved blocks */
 624         /*
 625          * These fields are for EXT4_DYNAMIC_REV superblocks only.
 626          *
 627          * Note: the difference between the compatible feature set and
 628          * the incompatible feature set is that if there is a bit set
 629          * in the incompatible feature set that the kernel doesn't
 630          * know about, it should refuse to mount the filesystem.
 631          *
 632          * e2fsck's requirements are more strict; if it doesn't know
 633          * about a feature in either the compatible or incompatible
 634          * feature set, it must abort and not try to meddle with
 635          * things it doesn't understand...
 636          */
 637         __le32  s_first_ino;            /* First non-reserved inode */
 638         __le16  s_inode_size;           /* size of inode structure */
 639         __le16  s_block_group_nr;       /* block group # of this superblock */
 640         __le32  s_feature_compat;       /* compatible feature set */
 641 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
 642         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
 643 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
 644 /*78*/  char    s_volume_name[16];      /* volume name */
 645 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
 646 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
 647         /*
 648          * Performance hints.  Directory preallocation should only
 649          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
 650          */
 651         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
 652         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
 653         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
 654         /*
 655          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
 656          */
 657 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
 658 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
 659         __le32  s_journal_dev;          /* device number of journal file */
 660         __le32  s_last_orphan;          /* start of list of inodes to delete */
 661         __le32  s_hash_seed[4];         /* HTREE hash seed */
 662         __u8    s_def_hash_version;     /* Default hash version to use */
 663         __u8    s_reserved_char_pad;
 664         __le16  s_desc_size;            /* size of group descriptor */
 665 /*100*/ __le32  s_default_mount_opts;
 666         __le32  s_first_meta_bg;        /* First metablock block group */
 667         __le32  s_mkfs_time;            /* When the filesystem was created */
 668         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
 669         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
 670 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
 671         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
 672         __le32  s_free_blocks_count_hi; /* Free blocks count */
 673         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
 674         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
 675         __le32  s_flags;                /* Miscellaneous flags */
 676         __le16  s_raid_stride;          /* RAID stride */
 677         __le16  s_mmp_interval;         /* # seconds to wait in MMP checking */
 678         __le64  s_mmp_block;            /* Block for multi-mount protection */
 679         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
 680         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
 681         __u8    s_reserved_char_pad2;
 682         __le16  s_reserved_pad;
 683         __u32   s_reserved[162];        /* Padding to the end of the block */
 684 };
 685
 686 #ifdef __KERNEL__
 687 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
 688 {
 689         return sb->s_fs_info;
 690 }
 691 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
 692 {
 693         return container_of(inode, struct ext4_inode_info, vfs_inode);
 694 }
 695
 696 static inline struct timespec ext4_current_time(struct inode *inode)
 697 {
 698         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
 699                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
 700 }
 701
 702
 703 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
 704 {
 705         return ino == EXT4_ROOT_INO ||
 706                 ino == EXT4_JOURNAL_INO ||
 707                 ino == EXT4_RESIZE_INO ||
 708                 (ino >= EXT4_FIRST_INO(sb) &&
 709                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
 710 }
 711 #else
 712 /* Assume that user mode programs are passing in an ext4fs superblock, not
 713  * a kernel struct super_block.  This will allow us to call the feature-test
 714  * macros from user land. */
 715 #define EXT4_SB(sb)     (sb)
 716 #endif
 717
 718 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
 719
 720 /*
 721  * Codes for operating systems
 722  */
 723 #define EXT4_OS_LINUX           0
 724 #define EXT4_OS_HURD            1
 725 #define EXT4_OS_MASIX           2
 726 #define EXT4_OS_FREEBSD         3
 727 #define EXT4_OS_LITES           4
 728
 729 /*
 730  * Revision levels
 731  */
 732 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
 733 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
 734
 735 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
 736 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
 737
 738 #define EXT4_GOOD_OLD_INODE_SIZE 128
 739
 740 /*
 741  * Feature set definitions
 742  */
 743
 744 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
 745         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
 746 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
 747         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
 748 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
 749         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
 750 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
 751         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
 752 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
 753         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
 754 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
 755         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
 756 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
 757         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
 758 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
 759         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
 760 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
 761         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
 762
 763 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
 764 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
 765 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
 766 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
 767 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
 768 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
 769
 770 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
 771 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
 772 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
 773 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
 774 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
 775 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
 776 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
 777
 778 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
 779 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
 780 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
 781 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
 782 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
 783 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
 784 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
 785 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
 786 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
 787
 788 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
 789 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
 790                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
 791                                          EXT4_FEATURE_INCOMPAT_META_BG| \
 792                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
 793                                          EXT4_FEATURE_INCOMPAT_64BIT| \
 794                                          EXT4_FEATURE_INCOMPAT_FLEX_BG)
 795 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
 796                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
 797                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
 798                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
 799                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
 800                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
 801                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
 802
 803 /*
 804  * Default values for user and/or group using reserved blocks
 805  */
 806 #define EXT4_DEF_RESUID         0
 807 #define EXT4_DEF_RESGID         0
 808
 809 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
 810
 811 /*
 812  * Default mount options
 813  */
 814 #define EXT4_DEFM_DEBUG         0x0001
 815 #define EXT4_DEFM_BSDGROUPS     0x0002
 816 #define EXT4_DEFM_XATTR_USER    0x0004
 817 #define EXT4_DEFM_ACL           0x0008
 818 #define EXT4_DEFM_UID16         0x0010
 819 #define EXT4_DEFM_JMODE         0x0060
 820 #define EXT4_DEFM_JMODE_DATA    0x0020
 821 #define EXT4_DEFM_JMODE_ORDERED 0x0040
 822 #define EXT4_DEFM_JMODE_WBACK   0x0060
 823
 824 /*
 825  * Default journal batch times
 826  */
 827 #define EXT4_DEF_MIN_BATCH_TIME 0
 828 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
 829
 830 /*
 831  * Structure of a directory entry
 832  */
 833 #define EXT4_NAME_LEN 255
 834
 835 struct ext4_dir_entry {
 836         __le32  inode;                  /* Inode number */
 837         __le16  rec_len;                /* Directory entry length */
 838         __le16  name_len;               /* Name length */
 839         char    name[EXT4_NAME_LEN];    /* File name */
 840 };
 841
 842 /*
 843  * The new version of the directory entry.  Since EXT4 structures are
 844  * stored in intel byte order, and the name_len field could never be
 845  * bigger than 255 chars, it's safe to reclaim the extra byte for the
 846  * file_type field.
 847  */
 848 struct ext4_dir_entry_2 {
 849         __le32  inode;                  /* Inode number */
 850         __le16  rec_len;                /* Directory entry length */
 851         __u8    name_len;               /* Name length */
 852         __u8    file_type;
 853         char    name[EXT4_NAME_LEN];    /* File name */
 854 };
 855
 856 /*
 857  * Ext4 directory file types.  Only the low 3 bits are used.  The
 858  * other bits are reserved for now.
 859  */
 860 #define EXT4_FT_UNKNOWN         0
 861 #define EXT4_FT_REG_FILE        1
 862 #define EXT4_FT_DIR             2
 863 #define EXT4_FT_CHRDEV          3
 864 #define EXT4_FT_BLKDEV          4
 865 #define EXT4_FT_FIFO            5
 866 #define EXT4_FT_SOCK            6
 867 #define EXT4_FT_SYMLINK         7
 868
 869 #define EXT4_FT_MAX             8
 870
 871 /*
 872  * EXT4_DIR_PAD defines the directory entries boundaries
 873  *
 874  * NOTE: It must be a multiple of 4
 875  */
 876 #define EXT4_DIR_PAD                    4
 877 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
 878 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
 879                                          ~EXT4_DIR_ROUND)
 880 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
 881
 882 /*
 883  * Hash Tree Directory indexing
 884  * (c) Daniel Phillips, 2001
 885  */
 886
 887 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
 888                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
 889                       (EXT4_I(dir)->i_flags & EXT4_INDEX_FL))
 890 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
 891 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
 892
 893 /* Legal values for the dx_root hash_version field: */
 894
 895 #define DX_HASH_LEGACY          0
 896 #define DX_HASH_HALF_MD4        1
 897 #define DX_HASH_TEA             2
 898 #define DX_HASH_LEGACY_UNSIGNED 3
 899 #define DX_HASH_HALF_MD4_UNSIGNED       4
 900 #define DX_HASH_TEA_UNSIGNED            5
 901
 902 #ifdef __KERNEL__
 903
 904 /* hash info structure used by the directory hash */
 905 struct dx_hash_info
 906 {
 907         u32             hash;
 908         u32             minor_hash;
 909         int             hash_version;
 910         u32             *seed;
 911 };
 912
 913 #define EXT4_HTREE_EOF  0x7fffffff
 914
 915 /*
 916  * Control parameters used by ext4_htree_next_block
 917  */
 918 #define HASH_NB_ALWAYS          1
 919
 920
 921 /*
 922  * Describe an inode's exact location on disk and in memory
 923  */
 924 struct ext4_iloc
 925 {
 926         struct buffer_head *bh;
 927         unsigned long offset;
 928         ext4_group_t block_group;
 929 };
 930
 931 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
 932 {
 933         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
 934 }
 935
 936 /*
 937  * This structure is stuffed into the struct file's private_data field
 938  * for directories.  It is where we put information so that we can do
 939  * readdir operations in hash tree order.
 940  */
 941 struct dir_private_info {
 942         struct rb_root  root;
 943         struct rb_node  *curr_node;
 944         struct fname    *extra_fname;
 945         loff_t          last_pos;
 946         __u32           curr_hash;
 947         __u32           curr_minor_hash;
 948         __u32           next_hash;
 949 };
 950
 951 /* calculate the first block number of the group */
 952 static inline ext4_fsblk_t
 953 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
 954 {
 955         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
 956                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
 957 }
 958
 959 /*
 960  * Special error return code only used by dx_probe() and its callers.
 961  */
 962 #define ERR_BAD_DX_DIR  -75000
 963
 964 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
 965                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
 966
 967 extern struct proc_dir_entry *ext4_proc_root;
 968
 969 #ifdef CONFIG_PROC_FS
 970 extern const struct file_operations ext4_ui_proc_fops;
 971
 972 #define EXT4_PROC_HANDLER(name, var)                                    \
 973 do {                                                                    \
 974         proc = proc_create_data(name, mode, sbi->s_proc,                \
 975                                 &ext4_ui_proc_fops, &sbi->s_##var);     \
 976         if (proc == NULL) {                                             \
 977                 printk(KERN_ERR "EXT4-fs: can't create %s\n", name);    \
 978                 goto err_out;                                           \
 979         }                                                               \
 980 } while (0)
 981 #else
 982 #define EXT4_PROC_HANDLER(name, var)
 983 #endif
 984
 985 /*
 986  * Function prototypes
 987  */
 988
 989 /*
 990  * Ok, these declarations are also in <linux/kernel.h> but none of the
 991  * ext4 source programs needs to include it so they are duplicated here.
 992  */
 993 # define NORET_TYPE     /**/
 994 # define ATTRIB_NORET   __attribute__((noreturn))
 995 # define NORET_AND      noreturn,
 996
 997 /* bitmap.c */
 998 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
 999
1000 /* balloc.c */
1001 extern unsigned int ext4_block_group(struct super_block *sb,
1002                         ext4_fsblk_t blocknr);
1003 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1004                         ext4_fsblk_t blocknr);
1005 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1006 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1007                         ext4_group_t group);
1008 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1009                         ext4_fsblk_t goal, unsigned long *count, int *errp);
1010 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1011 extern int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1012 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1013                         ext4_fsblk_t block, unsigned long count, int metadata);
1014 extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
1015                                 ext4_fsblk_t block, unsigned long count);
1016 extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);
1017 extern void ext4_check_blocks_bitmap(struct super_block *);
1018 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1019                                                     ext4_group_t block_group,
1020                                                     struct buffer_head ** bh);
1021 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1022
1023 /* dir.c */
1024 extern int ext4_check_dir_entry(const char *, struct inode *,
1025                                 struct ext4_dir_entry_2 *,
1026                                 struct buffer_head *, unsigned int);
1027 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1028                                     __u32 minor_hash,
1029                                     struct ext4_dir_entry_2 *dirent);
1030 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1031
1032 /* fsync.c */
1033 extern int ext4_sync_file(struct file *, struct dentry *, int);
1034
1035 /* hash.c */
1036 extern int ext4fs_dirhash(const char *name, int len, struct
1037                           dx_hash_info *hinfo);
1038
1039 /* ialloc.c */
1040 extern struct inode * ext4_new_inode(handle_t *, struct inode *, int);
1041 extern void ext4_free_inode(handle_t *, struct inode *);
1042 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1043 extern unsigned long ext4_count_free_inodes(struct super_block *);
1044 extern unsigned long ext4_count_dirs(struct super_block *);
1045 extern void ext4_check_inodes_bitmap(struct super_block *);
1046
1047 /* mballoc.c */
1048 extern long ext4_mb_stats;
1049 extern long ext4_mb_max_to_scan;
1050 extern int ext4_mb_init(struct super_block *, int);
1051 extern int ext4_mb_release(struct super_block *);
1052 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1053                                 struct ext4_allocation_request *, int *);
1054 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1055 extern void ext4_discard_preallocations(struct inode *);
1056 extern int __init init_ext4_mballoc(void);
1057 extern void exit_ext4_mballoc(void);
1058 extern void ext4_mb_free_blocks(handle_t *, struct inode *,
1059                 unsigned long, unsigned long, int, unsigned long *);
1060 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1061                 ext4_group_t i, struct ext4_group_desc *desc);
1062 extern void ext4_mb_update_group_info(struct ext4_group_info *grp,
1063                 ext4_grpblk_t add);
1064 extern int ext4_mb_get_buddy_cache_lock(struct super_block *, ext4_group_t);
1065 extern void ext4_mb_put_buddy_cache_lock(struct super_block *,
1066                                                 ext4_group_t, int);
1067 /* inode.c */
1068 int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode,
1069                 struct buffer_head *bh, ext4_fsblk_t blocknr);
1070 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1071                                                 ext4_lblk_t, int, int *);
1072 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1073                                                 ext4_lblk_t, int, int *);
1074 int ext4_get_block(struct inode *inode, sector_t iblock,
1075                                 struct buffer_head *bh_result, int create);
1076
1077 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1078 extern int  ext4_write_inode(struct inode *, int);
1079 extern int  ext4_setattr(struct dentry *, struct iattr *);
1080 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1081                                 struct kstat *stat);
1082 extern void ext4_delete_inode(struct inode *);
1083 extern int  ext4_sync_inode(handle_t *, struct inode *);
1084 extern void ext4_dirty_inode(struct inode *);
1085 extern int ext4_change_inode_journal_flag(struct inode *, int);
1086 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1087 extern int ext4_can_truncate(struct inode *inode);
1088 extern void ext4_truncate(struct inode *);
1089 extern void ext4_set_inode_flags(struct inode *);
1090 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1091 extern void ext4_set_aops(struct inode *inode);
1092 extern int ext4_writepage_trans_blocks(struct inode *);
1093 extern int ext4_meta_trans_blocks(struct inode *, int nrblocks, int idxblocks);
1094 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1095 extern int ext4_block_truncate_page(handle_t *handle,
1096                 struct address_space *mapping, loff_t from);
1097 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct page *page);
1098 extern qsize_t ext4_get_reserved_space(struct inode *inode);
1099
1100 /* ioctl.c */
1101 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1102 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1103
1104 /* migrate.c */
1105 extern int ext4_ext_migrate(struct inode *);
1106
1107 /* namei.c */
1108 extern unsigned int ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize);
1109 extern __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize);
1110 extern int ext4_orphan_add(handle_t *, struct inode *);
1111 extern int ext4_orphan_del(handle_t *, struct inode *);
1112 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1113                                 __u32 start_minor_hash, __u32 *next_hash);
1114
1115 /* resize.c */
1116 extern int ext4_group_add(struct super_block *sb,
1117                                 struct ext4_new_group_data *input);
1118 extern int ext4_group_extend(struct super_block *sb,
1119                                 struct ext4_super_block *es,
1120                                 ext4_fsblk_t n_blocks_count);
1121
1122 /* super.c */
1123 extern void ext4_error(struct super_block *, const char *, const char *, ...)
1124         __attribute__ ((format (printf, 3, 4)));
1125 extern void __ext4_std_error(struct super_block *, const char *, int);
1126 extern void ext4_abort(struct super_block *, const char *, const char *, ...)
1127         __attribute__ ((format (printf, 3, 4)));
1128 extern void ext4_warning(struct super_block *, const char *, const char *, ...)
1129         __attribute__ ((format (printf, 3, 4)));
1130 extern void ext4_grp_locked_error(struct super_block *, ext4_group_t,
1131                                 const char *, const char *, ...)
1132         __attribute__ ((format (printf, 4, 5)));
1133 extern void ext4_update_dynamic_rev(struct super_block *sb);
1134 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1135                                         __u32 compat);
1136 extern int ext4_update_rocompat_feature(handle_t *handle,
1137                                         struct super_block *sb, __u32 rocompat);
1138 extern int ext4_update_incompat_feature(handle_t *handle,
1139                                         struct super_block *sb, __u32 incompat);
1140 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
1141                                       struct ext4_group_desc *bg);
1142 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
1143                                       struct ext4_group_desc *bg);
1144 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
1145                                      struct ext4_group_desc *bg);
1146 extern __u32 ext4_free_blks_count(struct super_block *sb,
1147                                 struct ext4_group_desc *bg);
1148 extern __u32 ext4_free_inodes_count(struct super_block *sb,
1149                                  struct ext4_group_desc *bg);
1150 extern __u32 ext4_used_dirs_count(struct super_block *sb,
1151                                 struct ext4_group_desc *bg);
1152 extern __u32 ext4_itable_unused_count(struct super_block *sb,
1153                                    struct ext4_group_desc *bg);
1154 extern void ext4_block_bitmap_set(struct super_block *sb,
1155                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1156 extern void ext4_inode_bitmap_set(struct super_block *sb,
1157                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1158 extern void ext4_inode_table_set(struct super_block *sb,
1159                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
1160 extern void ext4_free_blks_set(struct super_block *sb,
1161                                struct ext4_group_desc *bg, __u32 count);
1162 extern void ext4_free_inodes_set(struct super_block *sb,
1163                                 struct ext4_group_desc *bg, __u32 count);
1164 extern void ext4_used_dirs_set(struct super_block *sb,
1165                                 struct ext4_group_desc *bg, __u32 count);
1166 extern void ext4_itable_unused_set(struct super_block *sb,
1167                                    struct ext4_group_desc *bg, __u32 count);
1168
1169 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
1170 {
1171         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
1172                 le32_to_cpu(es->s_blocks_count_lo);
1173 }
1174
1175 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
1176 {
1177         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
1178                 le32_to_cpu(es->s_r_blocks_count_lo);
1179 }
1180
1181 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
1182 {
1183         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
1184                 le32_to_cpu(es->s_free_blocks_count_lo);
1185 }
1186
1187 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
1188                                          ext4_fsblk_t blk)
1189 {
1190         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
1191         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
1192 }
1193
1194 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
1195                                               ext4_fsblk_t blk)
1196 {
1197         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
1198         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
1199 }
1200
1201 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
1202                                            ext4_fsblk_t blk)
1203 {
1204         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
1205         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
1206 }
1207
1208 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
1209 {
1210         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
1211                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
1212                         le32_to_cpu(raw_inode->i_size_lo);
1213         else
1214                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
1215 }
1216
1217 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
1218 {
1219         raw_inode->i_size_lo = cpu_to_le32(i_size);
1220         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
1221 }
1222
1223 static inline
1224 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
1225                                             ext4_group_t group)
1226 {
1227          struct ext4_group_info ***grp_info;
1228          long indexv, indexh;
1229          grp_info = EXT4_SB(sb)->s_group_info;
1230          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
1231          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
1232          return grp_info[indexv][indexh];
1233 }
1234
1235
1236 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
1237                                              ext4_group_t block_group)
1238 {
1239         return block_group >> sbi->s_log_groups_per_flex;
1240 }
1241
1242 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
1243 {
1244         return 1 << sbi->s_log_groups_per_flex;
1245 }
1246
1247 #define ext4_std_error(sb, errno)                               \
1248 do {                                                            \
1249         if ((errno))                                            \
1250                 __ext4_std_error((sb), __func__, (errno));      \
1251 } while (0)
1252
1253 #ifdef CONFIG_SMP
1254 /* Each CPU can accumulate percpu_counter_batch blocks in their local
1255  * counters. So we need to make sure we have free blocks more
1256  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
1257  */
1258 #define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
1259 #else
1260 #define EXT4_FREEBLOCKS_WATERMARK 0
1261 #endif
1262
1263 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
1264 {
1265         /*
1266          * XXX: replace with spinlock if seen contended -bzzz
1267          */
1268         down_write(&EXT4_I(inode)->i_data_sem);
1269         if (newsize > EXT4_I(inode)->i_disksize)
1270                 EXT4_I(inode)->i_disksize = newsize;
1271         up_write(&EXT4_I(inode)->i_data_sem);
1272         return ;
1273 }
1274
1275 struct ext4_group_info {
1276         unsigned long   bb_state;
1277         struct rb_root  bb_free_root;
1278         unsigned short  bb_first_free;
1279         unsigned short  bb_free;
1280         unsigned short  bb_fragments;
1281         struct          list_head bb_prealloc_list;
1282 #ifdef DOUBLE_CHECK
1283         void            *bb_bitmap;
1284 #endif
1285         struct rw_semaphore alloc_sem;
1286         unsigned short  bb_counters[];
1287 };
1288
1289 #define EXT4_GROUP_INFO_NEED_INIT_BIT   0
1290 #define EXT4_GROUP_INFO_LOCKED_BIT      1
1291
1292 #define EXT4_MB_GRP_NEED_INIT(grp)      \
1293         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
1294
1295 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
1296 {
1297         struct ext4_group_info *grinfo = ext4_get_group_info(sb, group);
1298
1299         bit_spin_lock(EXT4_GROUP_INFO_LOCKED_BIT, &(grinfo->bb_state));
1300 }
1301
1302 static inline void ext4_unlock_group(struct super_block *sb,
1303                                         ext4_group_t group)
1304 {
1305         struct ext4_group_info *grinfo = ext4_get_group_info(sb, group);
1306
1307         bit_spin_unlock(EXT4_GROUP_INFO_LOCKED_BIT, &(grinfo->bb_state));
1308 }
1309
1310 static inline int ext4_is_group_locked(struct super_block *sb,
1311                                         ext4_group_t group)
1312 {
1313         struct ext4_group_info *grinfo = ext4_get_group_info(sb, group);
1314
1315         return bit_spin_is_locked(EXT4_GROUP_INFO_LOCKED_BIT,
1316                                                 &(grinfo->bb_state));
1317 }
1318
1319 /*
1320  * Inodes and files operations
1321  */
1322
1323 /* dir.c */
1324 extern const struct file_operations ext4_dir_operations;
1325
1326 /* file.c */
1327 extern const struct inode_operations ext4_file_inode_operations;
1328 extern const struct file_operations ext4_file_operations;
1329
1330 /* namei.c */
1331 extern const struct inode_operations ext4_dir_inode_operations;
1332 extern const struct inode_operations ext4_special_inode_operations;
1333
1334 /* symlink.c */
1335 extern const struct inode_operations ext4_symlink_inode_operations;
1336 extern const struct inode_operations ext4_fast_symlink_inode_operations;
1337
1338 /* extents.c */
1339 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
1340 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
1341 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
1342                                        int chunk);
1343 extern int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
1344                                ext4_lblk_t iblock, unsigned int max_blocks,
1345                                struct buffer_head *bh_result,
1346                                int create, int extend_disksize);
1347 extern void ext4_ext_truncate(struct inode *);
1348 extern void ext4_ext_init(struct super_block *);
1349 extern void ext4_ext_release(struct super_block *);
1350 extern long ext4_fallocate(struct inode *inode, int mode, loff_t offset,
1351                           loff_t len);
1352 extern int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode,
1353                         sector_t block, unsigned int max_blocks,
1354                         struct buffer_head *bh, int create,
1355                         int extend_disksize, int flag);
1356 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1357                         __u64 start, __u64 len);
1358
1359 /*
1360  * Add new method to test wether block and inode bitmaps are properly
1361  * initialized. With uninit_bg reading the block from disk is not enough
1362  * to mark the bitmap uptodate. We need to also zero-out the bitmap
1363  */
1364 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
1365
1366 static inline int bitmap_uptodate(struct buffer_head *bh)
1367 {
1368         return (buffer_uptodate(bh) &&
1369                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
1370 }
1371 static inline void set_bitmap_uptodate(struct buffer_head *bh)
1372 {
1373         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
1374 }
1375
1376 #endif  /* __KERNEL__ */
1377
1378 #endif  /* _EXT4_H */