fs/ext4/ext4.h

   1 /*
   2  *  ext4.h
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/include/linux/minix_fs.h
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  */
  15
  16 #ifndef _EXT4_H
  17 #define _EXT4_H
  18
  19 #include <linux/types.h>
  20 #include <linux/blkdev.h>
  21 #include <linux/magic.h>
  22 #include <linux/jbd2.h>
  23 #include <linux/quota.h>
  24 #include "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         atomic_t free_inodes;
 174         atomic_t free_blocks;
 175         atomic_t used_dirs;
 176 };
 177
 178 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
 179 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
 180 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
 181
 182 #ifdef __KERNEL__
 183 #include "ext4_sb.h"
 184 #endif
 185 /*
 186  * Macro-instructions used to manage group descriptors
 187  */
 188 #define EXT4_MIN_DESC_SIZE              32
 189 #define EXT4_MIN_DESC_SIZE_64BIT        64
 190 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
 191 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
 192 #ifdef __KERNEL__
 193 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 194 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 195 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 196 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 197 #else
 198 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 199 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 200 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 201 #endif
 202
 203 /*
 204  * Constants relative to the data blocks
 205  */
 206 #define EXT4_NDIR_BLOCKS                12
 207 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 208 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 209 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 210 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 211
 212 /*
 213  * Inode flags
 214  */
 215 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 216 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 217 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 218 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 219 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 220 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 221 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 222 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 223 /* Reserved for compression usage... */
 224 #define EXT4_DIRTY_FL                   0x00000100
 225 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 226 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 227 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
 228 /* End compression flags --- maybe not all used */
 229 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 230 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 231 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 232 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 233 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 234 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 235 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 236 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 237 #define EXT4_EXT_MIGRATE                0x00100000 /* Inode is migrating */
 238 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 239
 240 #define EXT4_FL_USER_VISIBLE            0x000BDFFF /* User visible flags */
 241 #define EXT4_FL_USER_MODIFIABLE         0x000B80FF /* User modifiable flags */
 242
 243 /* Flags that should be inherited by new inodes from their parent. */
 244 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 245                            EXT4_SYNC_FL | EXT4_IMMUTABLE_FL | EXT4_APPEND_FL |\
 246                            EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 247                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 248                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
 249
 250 /* Flags that are appropriate for regular files (all but dir-specific ones). */
 251 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
 252
 253 /* Flags that are appropriate for non-directories/regular files. */
 254 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 255
 256 /* Mask out flags that are inappropriate for the given type of inode. */
 257 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 258 {
 259         if (S_ISDIR(mode))
 260                 return flags;
 261         else if (S_ISREG(mode))
 262                 return flags & EXT4_REG_FLMASK;
 263         else
 264                 return flags & EXT4_OTHER_FLMASK;
 265 }
 266
 267 /*
 268  * Inode dynamic state flags
 269  */
 270 #define EXT4_STATE_JDATA                0x00000001 /* journaled data exists */
 271 #define EXT4_STATE_NEW                  0x00000002 /* inode is newly created */
 272 #define EXT4_STATE_XATTR                0x00000004 /* has in-inode xattrs */
 273 #define EXT4_STATE_NO_EXPAND            0x00000008 /* No space for expansion */
 274 #define EXT4_STATE_DA_ALLOC_CLOSE       0x00000010 /* Alloc DA blks on close */
 275
 276 /* Used to pass group descriptor data when online resize is done */
 277 struct ext4_new_group_input {
 278         __u32 group;            /* Group number for this data */
 279         __u64 block_bitmap;     /* Absolute block number of block bitmap */
 280         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
 281         __u64 inode_table;      /* Absolute block number of inode table start */
 282         __u32 blocks_count;     /* Total number of blocks in this group */
 283         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 284         __u16 unused;
 285 };
 286
 287 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 288 struct ext4_new_group_data {
 289         __u32 group;
 290         __u64 block_bitmap;
 291         __u64 inode_bitmap;
 292         __u64 inode_table;
 293         __u32 blocks_count;
 294         __u16 reserved_blocks;
 295         __u16 unused;
 296         __u32 free_blocks_count;
 297 };
 298
 299 /*
 300  * Following is used by preallocation code to tell get_blocks() that we
 301  * want uninitialzed extents.
 302  */
 303 #define EXT4_CREATE_UNINITIALIZED_EXT           2
 304
 305 /*
 306  * ioctl commands
 307  */
 308 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
 309 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
 310 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 311 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 312 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 313 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 314 #ifdef CONFIG_JBD2_DEBUG
 315 #define EXT4_IOC_WAIT_FOR_READONLY      _IOR('f', 99, long)
 316 #endif
 317 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 318 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 319 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 320 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
 321 #define EXT4_IOC_MIGRATE                _IO('f', 9)
 322  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
 323  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 324 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
 325
 326 /*
 327  * ioctl commands in 32 bit emulation
 328  */
 329 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
 330 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
 331 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 332 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 333 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 334 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 335 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 336 #ifdef CONFIG_JBD2_DEBUG
 337 #define EXT4_IOC32_WAIT_FOR_READONLY    _IOR('f', 99, int)
 338 #endif
 339 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 340 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 341
 342
 343 /*
 344  *  Mount options
 345  */
 346 struct ext4_mount_options {
 347         unsigned long s_mount_opt;
 348         uid_t s_resuid;
 349         gid_t s_resgid;
 350         unsigned long s_commit_interval;
 351         u32 s_min_batch_time, s_max_batch_time;
 352 #ifdef CONFIG_QUOTA
 353         int s_jquota_fmt;
 354         char *s_qf_names[MAXQUOTAS];
 355 #endif
 356 };
 357
 358 /*
 359  * Structure of an inode on the disk
 360  */
 361 struct ext4_inode {
 362         __le16  i_mode;         /* File mode */
 363         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 364         __le32  i_size_lo;      /* Size in bytes */
 365         __le32  i_atime;        /* Access time */
 366         __le32  i_ctime;        /* Inode Change time */
 367         __le32  i_mtime;        /* Modification time */
 368         __le32  i_dtime;        /* Deletion Time */
 369         __le16  i_gid;          /* Low 16 bits of Group Id */
 370         __le16  i_links_count;  /* Links count */
 371         __le32  i_blocks_lo;    /* Blocks count */
 372         __le32  i_flags;        /* File flags */
 373         union {
 374                 struct {
 375                         __le32  l_i_version;
 376                 } linux1;
 377                 struct {
 378                         __u32  h_i_translator;
 379                 } hurd1;
 380                 struct {
 381                         __u32  m_i_reserved1;
 382                 } masix1;
 383         } osd1;                         /* OS dependent 1 */
 384         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 385         __le32  i_generation;   /* File version (for NFS) */
 386         __le32  i_file_acl_lo;  /* File ACL */
 387         __le32  i_size_high;
 388         __le32  i_obso_faddr;   /* Obsoleted fragment address */
 389         union {
 390                 struct {
 391                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
 392                         __le16  l_i_file_acl_high;
 393                         __le16  l_i_uid_high;   /* these 2 fields */
 394                         __le16  l_i_gid_high;   /* were reserved2[0] */
 395                         __u32   l_i_reserved2;
 396                 } linux2;
 397                 struct {
 398                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 399                         __u16   h_i_mode_high;
 400                         __u16   h_i_uid_high;
 401                         __u16   h_i_gid_high;
 402                         __u32   h_i_author;
 403                 } hurd2;
 404                 struct {
 405                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 406                         __le16  m_i_file_acl_high;
 407                         __u32   m_i_reserved2[2];
 408                 } masix2;
 409         } osd2;                         /* OS dependent 2 */
 410         __le16  i_extra_isize;
 411         __le16  i_pad1;
 412         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 413         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 414         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 415         __le32  i_crtime;       /* File Creation time */
 416         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 417         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 418 };
 419
 420
 421 #define EXT4_EPOCH_BITS 2
 422 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 423 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 424
 425 /*
 426  * Extended fields will fit into an inode if the filesystem was formatted
 427  * with large inodes (-I 256 or larger) and there are not currently any EAs
 428  * consuming all of the available space. For new inodes we always reserve
 429  * enough space for the kernel's known extended fields, but for inodes
 430  * created with an old kernel this might not have been the case. None of
 431  * the extended inode fields is critical for correct filesystem operation.
 432  * This macro checks if a certain field fits in the inode. Note that
 433  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 434  */
 435 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 436         ((offsetof(typeof(*ext4_inode), field) +        \
 437           sizeof((ext4_inode)->field))                  \
 438         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 439             (einode)->i_extra_isize))                   \
 440
 441 static inline __le32 ext4_encode_extra_time(struct timespec *time)
 442 {
 443        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 444                            time->tv_sec >> 32 : 0) |
 445                            ((time->tv_nsec << 2) & EXT4_NSEC_MASK));
 446 }
 447
 448 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 449 {
 450        if (sizeof(time->tv_sec) > 4)
 451                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 452                                << 32;
 453        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> 2;
 454 }
 455
 456 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
 457 do {                                                                           \
 458         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
 459         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 460                 (raw_inode)->xtime ## _extra =                                 \
 461                                 ext4_encode_extra_time(&(inode)->xtime);       \
 462 } while (0)
 463
 464 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 465 do {                                                                           \
 466         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 467                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 468         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 469                 (raw_inode)->xtime ## _extra =                                 \
 470                                 ext4_encode_extra_time(&(einode)->xtime);      \
 471 } while (0)
 472
 473 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
 474 do {                                                                           \
 475         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 476         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 477                 ext4_decode_extra_time(&(inode)->xtime,                        \
 478                                        raw_inode->xtime ## _extra);            \
 479 } while (0)
 480
 481 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 482 do {                                                                           \
 483         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 484                 (einode)->xtime.tv_sec =                                       \
 485                         (signed)le32_to_cpu((raw_inode)->xtime);               \
 486         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 487                 ext4_decode_extra_time(&(einode)->xtime,                       \
 488                                        raw_inode->xtime ## _extra);            \
 489 } while (0)
 490
 491 #define i_disk_version osd1.linux1.l_i_version
 492
 493 #if defined(__KERNEL__) || defined(__linux__)
 494 #define i_reserved1     osd1.linux1.l_i_reserved1
 495 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 496 #define i_blocks_high   osd2.linux2.l_i_blocks_high
 497 #define i_uid_low       i_uid
 498 #define i_gid_low       i_gid
 499 #define i_uid_high      osd2.linux2.l_i_uid_high
 500 #define i_gid_high      osd2.linux2.l_i_gid_high
 501 #define i_reserved2     osd2.linux2.l_i_reserved2
 502
 503 #elif defined(__GNU__)
 504
 505 #define i_translator    osd1.hurd1.h_i_translator
 506 #define i_uid_high      osd2.hurd2.h_i_uid_high
 507 #define i_gid_high      osd2.hurd2.h_i_gid_high
 508 #define i_author        osd2.hurd2.h_i_author
 509
 510 #elif defined(__masix__)
 511
 512 #define i_reserved1     osd1.masix1.m_i_reserved1
 513 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 514 #define i_reserved2     osd2.masix2.m_i_reserved2
 515
 516 #endif /* defined(__KERNEL__) || defined(__linux__) */
 517
 518 /*
 519  * File system states
 520  */
 521 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
 522 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
 523 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 524
 525 /*
 526  * Misc. filesystem flags
 527  */
 528 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
 529 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
 530 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
 531
 532 /*
 533  * Mount flags
 534  */
 535 #define EXT4_MOUNT_OLDALLOC             0x00002  /* Don't use the new Orlov allocator */
 536 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
 537 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
 538 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
 539 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
 540 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
 541 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
 542 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
 543 #define EXT4_MOUNT_ABORT                0x00200 /* Fatal error detected */
 544 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
 545 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
 546 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
 547 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
 548 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
 549 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
 550 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
 551 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
 552 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
 553 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
 554 #define EXT4_MOUNT_NOBH                 0x40000 /* No bufferheads */
 555 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
 556 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
 557 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
 558 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
 559 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
 560 #define EXT4_MOUNT_I_VERSION            0x2000000 /* i_version support */
 561 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
 562 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
 563
 564 /* Compatibility, for having both ext2_fs.h and ext4_fs.h included at once */
 565 #ifndef _LINUX_EXT2_FS_H
 566 #define clear_opt(o, opt)               o &= ~EXT4_MOUNT_##opt
 567 #define set_opt(o, opt)                 o |= EXT4_MOUNT_##opt
 568 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
 569                                          EXT4_MOUNT_##opt)
 570 #else
 571 #define EXT2_MOUNT_NOLOAD               EXT4_MOUNT_NOLOAD
 572 #define EXT2_MOUNT_ABORT                EXT4_MOUNT_ABORT
 573 #define EXT2_MOUNT_DATA_FLAGS           EXT4_MOUNT_DATA_FLAGS
 574 #endif
 575
 576 #define ext4_set_bit                    ext2_set_bit
 577 #define ext4_set_bit_atomic             ext2_set_bit_atomic
 578 #define ext4_clear_bit                  ext2_clear_bit
 579 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
 580 #define ext4_test_bit                   ext2_test_bit
 581 #define ext4_find_first_zero_bit        ext2_find_first_zero_bit
 582 #define ext4_find_next_zero_bit         ext2_find_next_zero_bit
 583 #define ext4_find_next_bit              ext2_find_next_bit
 584
 585 /*
 586  * Maximal mount counts between two filesystem checks
 587  */
 588 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
 589 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
 590
 591 /*
 592  * Behaviour when detecting errors
 593  */
 594 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
 595 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
 596 #define EXT4_ERRORS_PANIC               3       /* Panic */
 597 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
 598
 599 /*
 600  * Structure of the super block
 601  */
 602 struct ext4_super_block {
 603 /*00*/  __le32  s_inodes_count;         /* Inodes count */
 604         __le32  s_blocks_count_lo;      /* Blocks count */
 605         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
 606         __le32  s_free_blocks_count_lo; /* Free blocks count */
 607 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
 608         __le32  s_first_data_block;     /* First Data Block */
 609         __le32  s_log_block_size;       /* Block size */
 610         __le32  s_obso_log_frag_size;   /* Obsoleted fragment size */
 611 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
 612         __le32  s_obso_frags_per_group; /* Obsoleted fragments per group */
 613         __le32  s_inodes_per_group;     /* # Inodes per group */
 614         __le32  s_mtime;                /* Mount time */
 615 /*30*/  __le32  s_wtime;                /* Write time */
 616         __le16  s_mnt_count;            /* Mount count */
 617         __le16  s_max_mnt_count;        /* Maximal mount count */
 618         __le16  s_magic;                /* Magic signature */
 619         __le16  s_state;                /* File system state */
 620         __le16  s_errors;               /* Behaviour when detecting errors */
 621         __le16  s_minor_rev_level;      /* minor revision level */
 622 /*40*/  __le32  s_lastcheck;            /* time of last check */
 623         __le32  s_checkinterval;        /* max. time between checks */
 624         __le32  s_creator_os;           /* OS */
 625         __le32  s_rev_level;            /* Revision level */
 626 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
 627         __le16  s_def_resgid;           /* Default gid for reserved blocks */
 628         /*
 629          * These fields are for EXT4_DYNAMIC_REV superblocks only.
 630          *
 631          * Note: the difference between the compatible feature set and
 632          * the incompatible feature set is that if there is a bit set
 633          * in the incompatible feature set that the kernel doesn't
 634          * know about, it should refuse to mount the filesystem.
 635          *
 636          * e2fsck's requirements are more strict; if it doesn't know
 637          * about a feature in either the compatible or incompatible
 638          * feature set, it must abort and not try to meddle with
 639          * things it doesn't understand...
 640          */
 641         __le32  s_first_ino;            /* First non-reserved inode */
 642         __le16  s_inode_size;           /* size of inode structure */
 643         __le16  s_block_group_nr;       /* block group # of this superblock */
 644         __le32  s_feature_compat;       /* compatible feature set */
 645 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
 646         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
 647 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
 648 /*78*/  char    s_volume_name[16];      /* volume name */
 649 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
 650 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
 651         /*
 652          * Performance hints.  Directory preallocation should only
 653          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
 654          */
 655         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
 656         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
 657         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
 658         /*
 659          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
 660          */
 661 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
 662 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
 663         __le32  s_journal_dev;          /* device number of journal file */
 664         __le32  s_last_orphan;          /* start of list of inodes to delete */
 665         __le32  s_hash_seed[4];         /* HTREE hash seed */
 666         __u8    s_def_hash_version;     /* Default hash version to use */
 667         __u8    s_reserved_char_pad;
 668         __le16  s_desc_size;            /* size of group descriptor */
 669 /*100*/ __le32  s_default_mount_opts;
 670         __le32  s_first_meta_bg;        /* First metablock block group */
 671         __le32  s_mkfs_time;            /* When the filesystem was created */
 672         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
 673         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
 674 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
 675         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
 676         __le32  s_free_blocks_count_hi; /* Free blocks count */
 677         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
 678         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
 679         __le32  s_flags;                /* Miscellaneous flags */
 680         __le16  s_raid_stride;          /* RAID stride */
 681         __le16  s_mmp_interval;         /* # seconds to wait in MMP checking */
 682         __le64  s_mmp_block;            /* Block for multi-mount protection */
 683         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
 684         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
 685         __u8    s_reserved_char_pad2;
 686         __le16  s_reserved_pad;
 687         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
 688         __u32   s_reserved[160];        /* Padding to the end of the block */
 689 };
 690
 691 #ifdef __KERNEL__
 692 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
 693 {
 694         return sb->s_fs_info;
 695 }
 696 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
 697 {
 698         return container_of(inode, struct ext4_inode_info, vfs_inode);
 699 }
 700
 701 static inline struct timespec ext4_current_time(struct inode *inode)
 702 {
 703         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
 704                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
 705 }
 706
 707
 708 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
 709 {
 710         return ino == EXT4_ROOT_INO ||
 711                 ino == EXT4_JOURNAL_INO ||
 712                 ino == EXT4_RESIZE_INO ||
 713                 (ino >= EXT4_FIRST_INO(sb) &&
 714                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
 715 }
 716 #else
 717 /* Assume that user mode programs are passing in an ext4fs superblock, not
 718  * a kernel struct super_block.  This will allow us to call the feature-test
 719  * macros from user land. */
 720 #define EXT4_SB(sb)     (sb)
 721 #endif
 722
 723 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
 724
 725 /*
 726  * Codes for operating systems
 727  */
 728 #define EXT4_OS_LINUX           0
 729 #define EXT4_OS_HURD            1
 730 #define EXT4_OS_MASIX           2
 731 #define EXT4_OS_FREEBSD         3
 732 #define EXT4_OS_LITES           4
 733
 734 /*
 735  * Revision levels
 736  */
 737 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
 738 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
 739
 740 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
 741 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
 742
 743 #define EXT4_GOOD_OLD_INODE_SIZE 128
 744
 745 /*
 746  * Feature set definitions
 747  */
 748
 749 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
 750         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
 751 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
 752         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
 753 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
 754         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
 755 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
 756         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
 757 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
 758         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
 759 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
 760         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
 761 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
 762         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
 763 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
 764         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
 765 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
 766         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
 767
 768 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
 769 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
 770 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
 771 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
 772 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
 773 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
 774
 775 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
 776 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
 777 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
 778 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
 779 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
 780 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
 781 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
 782
 783 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
 784 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
 785 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
 786 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
 787 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
 788 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
 789 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
 790 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
 791 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
 792
 793 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
 794 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
 795                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
 796                                          EXT4_FEATURE_INCOMPAT_META_BG| \
 797                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
 798                                          EXT4_FEATURE_INCOMPAT_64BIT| \
 799                                          EXT4_FEATURE_INCOMPAT_FLEX_BG)
 800 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
 801                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
 802                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
 803                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
 804                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
 805                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
 806                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
 807
 808 /*
 809  * Default values for user and/or group using reserved blocks
 810  */
 811 #define EXT4_DEF_RESUID         0
 812 #define EXT4_DEF_RESGID         0
 813
 814 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
 815
 816 /*
 817  * Default mount options
 818  */
 819 #define EXT4_DEFM_DEBUG         0x0001
 820 #define EXT4_DEFM_BSDGROUPS     0x0002
 821 #define EXT4_DEFM_XATTR_USER    0x0004
 822 #define EXT4_DEFM_ACL           0x0008
 823 #define EXT4_DEFM_UID16         0x0010
 824 #define EXT4_DEFM_JMODE         0x0060
 825 #define EXT4_DEFM_JMODE_DATA    0x0020
 826 #define EXT4_DEFM_JMODE_ORDERED 0x0040
 827 #define EXT4_DEFM_JMODE_WBACK   0x0060
 828
 829 /*
 830  * Default journal batch times
 831  */
 832 #define EXT4_DEF_MIN_BATCH_TIME 0
 833 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
 834
 835 /*
 836  * Minimum number of groups in a flexgroup before we separate out
 837  * directories into the first block group of a flexgroup
 838  */
 839 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
 840
 841 /*
 842  * Structure of a directory entry
 843  */
 844 #define EXT4_NAME_LEN 255
 845
 846 struct ext4_dir_entry {
 847         __le32  inode;                  /* Inode number */
 848         __le16  rec_len;                /* Directory entry length */
 849         __le16  name_len;               /* Name length */
 850         char    name[EXT4_NAME_LEN];    /* File name */
 851 };
 852
 853 /*
 854  * The new version of the directory entry.  Since EXT4 structures are
 855  * stored in intel byte order, and the name_len field could never be
 856  * bigger than 255 chars, it's safe to reclaim the extra byte for the
 857  * file_type field.
 858  */
 859 struct ext4_dir_entry_2 {
 860         __le32  inode;                  /* Inode number */
 861         __le16  rec_len;                /* Directory entry length */
 862         __u8    name_len;               /* Name length */
 863         __u8    file_type;
 864         char    name[EXT4_NAME_LEN];    /* File name */
 865 };
 866
 867 /*
 868  * Ext4 directory file types.  Only the low 3 bits are used.  The
 869  * other bits are reserved for now.
 870  */
 871 #define EXT4_FT_UNKNOWN         0
 872 #define EXT4_FT_REG_FILE        1
 873 #define EXT4_FT_DIR             2
 874 #define EXT4_FT_CHRDEV          3
 875 #define EXT4_FT_BLKDEV          4
 876 #define EXT4_FT_FIFO            5
 877 #define EXT4_FT_SOCK            6
 878 #define EXT4_FT_SYMLINK         7
 879
 880 #define EXT4_FT_MAX             8
 881
 882 /*
 883  * EXT4_DIR_PAD defines the directory entries boundaries
 884  *
 885  * NOTE: It must be a multiple of 4
 886  */
 887 #define EXT4_DIR_PAD                    4
 888 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
 889 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
 890                                          ~EXT4_DIR_ROUND)
 891 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
 892
 893 /*
 894  * Hash Tree Directory indexing
 895  * (c) Daniel Phillips, 2001
 896  */
 897
 898 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
 899                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
 900                       (EXT4_I(dir)->i_flags & EXT4_INDEX_FL))
 901 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
 902 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
 903
 904 /* Legal values for the dx_root hash_version field: */
 905
 906 #define DX_HASH_LEGACY          0
 907 #define DX_HASH_HALF_MD4        1
 908 #define DX_HASH_TEA             2
 909 #define DX_HASH_LEGACY_UNSIGNED 3
 910 #define DX_HASH_HALF_MD4_UNSIGNED       4
 911 #define DX_HASH_TEA_UNSIGNED            5
 912
 913 #ifdef __KERNEL__
 914
 915 /* hash info structure used by the directory hash */
 916 struct dx_hash_info
 917 {
 918         u32             hash;
 919         u32             minor_hash;
 920         int             hash_version;
 921         u32             *seed;
 922 };
 923
 924 #define EXT4_HTREE_EOF  0x7fffffff
 925
 926 /*
 927  * Control parameters used by ext4_htree_next_block
 928  */
 929 #define HASH_NB_ALWAYS          1
 930
 931
 932 /*
 933  * Describe an inode's exact location on disk and in memory
 934  */
 935 struct ext4_iloc
 936 {
 937         struct buffer_head *bh;
 938         unsigned long offset;
 939         ext4_group_t block_group;
 940 };
 941
 942 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
 943 {
 944         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
 945 }
 946
 947 /*
 948  * This structure is stuffed into the struct file's private_data field
 949  * for directories.  It is where we put information so that we can do
 950  * readdir operations in hash tree order.
 951  */
 952 struct dir_private_info {
 953         struct rb_root  root;
 954         struct rb_node  *curr_node;
 955         struct fname    *extra_fname;
 956         loff_t          last_pos;
 957         __u32           curr_hash;
 958         __u32           curr_minor_hash;
 959         __u32           next_hash;
 960 };
 961
 962 /* calculate the first block number of the group */
 963 static inline ext4_fsblk_t
 964 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
 965 {
 966         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
 967                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
 968 }
 969
 970 /*
 971  * Special error return code only used by dx_probe() and its callers.
 972  */
 973 #define ERR_BAD_DX_DIR  -75000
 974
 975 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
 976                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
 977
 978 extern struct proc_dir_entry *ext4_proc_root;
 979
 980 /*
 981  * Function prototypes
 982  */
 983
 984 /*
 985  * Ok, these declarations are also in <linux/kernel.h> but none of the
 986  * ext4 source programs needs to include it so they are duplicated here.
 987  */
 988 # define NORET_TYPE     /**/
 989 # define ATTRIB_NORET   __attribute__((noreturn))
 990 # define NORET_AND      noreturn,
 991
 992 /* bitmap.c */
 993 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
 994
 995 /* balloc.c */
 996 extern unsigned int ext4_block_group(struct super_block *sb,
 997                         ext4_fsblk_t blocknr);
 998 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
 999                         ext4_fsblk_t blocknr);
1000 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1001 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1002                         ext4_group_t group);
1003 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1004                         ext4_fsblk_t goal, unsigned long *count, int *errp);
1005 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1006 extern int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1007 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1008                         ext4_fsblk_t block, unsigned long count, int metadata);
1009 extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
1010                                 ext4_fsblk_t block, unsigned long count);
1011 extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);
1012 extern void ext4_check_blocks_bitmap(struct super_block *);
1013 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1014                                                     ext4_group_t block_group,
1015                                                     struct buffer_head ** bh);
1016 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1017
1018 /* dir.c */
1019 extern int ext4_check_dir_entry(const char *, struct inode *,
1020                                 struct ext4_dir_entry_2 *,
1021                                 struct buffer_head *, unsigned int);
1022 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1023                                     __u32 minor_hash,
1024                                     struct ext4_dir_entry_2 *dirent);
1025 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1026
1027 /* fsync.c */
1028 extern int ext4_sync_file(struct file *, struct dentry *, int);
1029
1030 /* hash.c */
1031 extern int ext4fs_dirhash(const char *name, int len, struct
1032                           dx_hash_info *hinfo);
1033
1034 /* ialloc.c */
1035 extern struct inode * ext4_new_inode(handle_t *, struct inode *, int);
1036 extern void ext4_free_inode(handle_t *, struct inode *);
1037 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1038 extern unsigned long ext4_count_free_inodes(struct super_block *);
1039 extern unsigned long ext4_count_dirs(struct super_block *);
1040 extern void ext4_check_inodes_bitmap(struct super_block *);
1041
1042 /* mballoc.c */
1043 extern long ext4_mb_stats;
1044 extern long ext4_mb_max_to_scan;
1045 extern int ext4_mb_init(struct super_block *, int);
1046 extern int ext4_mb_release(struct super_block *);
1047 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1048                                 struct ext4_allocation_request *, int *);
1049 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1050 extern void ext4_discard_preallocations(struct inode *);
1051 extern int __init init_ext4_mballoc(void);
1052 extern void exit_ext4_mballoc(void);
1053 extern void ext4_mb_free_blocks(handle_t *, struct inode *,
1054                 unsigned long, unsigned long, int, unsigned long *);
1055 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1056                 ext4_group_t i, struct ext4_group_desc *desc);
1057 extern void ext4_mb_update_group_info(struct ext4_group_info *grp,
1058                 ext4_grpblk_t add);
1059 extern int ext4_mb_get_buddy_cache_lock(struct super_block *, ext4_group_t);
1060 extern void ext4_mb_put_buddy_cache_lock(struct super_block *,
1061                                                 ext4_group_t, int);
1062 /* inode.c */
1063 int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode,
1064                 struct buffer_head *bh, ext4_fsblk_t blocknr);
1065 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1066                                                 ext4_lblk_t, int, int *);
1067 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1068                                                 ext4_lblk_t, int, int *);
1069 int ext4_get_block(struct inode *inode, sector_t iblock,
1070                                 struct buffer_head *bh_result, int create);
1071
1072 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1073 extern int  ext4_write_inode(struct inode *, int);
1074 extern int  ext4_setattr(struct dentry *, struct iattr *);
1075 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1076                                 struct kstat *stat);
1077 extern void ext4_delete_inode(struct inode *);
1078 extern int  ext4_sync_inode(handle_t *, struct inode *);
1079 extern void ext4_dirty_inode(struct inode *);
1080 extern int ext4_change_inode_journal_flag(struct inode *, int);
1081 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1082 extern int ext4_can_truncate(struct inode *inode);
1083 extern void ext4_truncate(struct inode *);
1084 extern void ext4_set_inode_flags(struct inode *);
1085 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1086 extern int ext4_alloc_da_blocks(struct inode *inode);
1087 extern void ext4_set_aops(struct inode *inode);
1088 extern int ext4_writepage_trans_blocks(struct inode *);
1089 extern int ext4_meta_trans_blocks(struct inode *, int nrblocks, int idxblocks);
1090 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1091 extern int ext4_block_truncate_page(handle_t *handle,
1092                 struct address_space *mapping, loff_t from);
1093 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1094 extern qsize_t ext4_get_reserved_space(struct inode *inode);
1095
1096 /* ioctl.c */
1097 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1098 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1099
1100 /* migrate.c */
1101 extern int ext4_ext_migrate(struct inode *);
1102
1103 /* namei.c */
1104 extern unsigned int ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize);
1105 extern __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize);
1106 extern int ext4_orphan_add(handle_t *, struct inode *);
1107 extern int ext4_orphan_del(handle_t *, struct inode *);
1108 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1109                                 __u32 start_minor_hash, __u32 *next_hash);
1110
1111 /* resize.c */
1112 extern int ext4_group_add(struct super_block *sb,
1113                                 struct ext4_new_group_data *input);
1114 extern int ext4_group_extend(struct super_block *sb,
1115                                 struct ext4_super_block *es,
1116                                 ext4_fsblk_t n_blocks_count);
1117
1118 /* super.c */
1119 extern void ext4_error(struct super_block *, const char *, const char *, ...)
1120         __attribute__ ((format (printf, 3, 4)));
1121 extern void __ext4_std_error(struct super_block *, const char *, int);
1122 extern void ext4_abort(struct super_block *, const char *, const char *, ...)
1123         __attribute__ ((format (printf, 3, 4)));
1124 extern void ext4_warning(struct super_block *, const char *, const char *, ...)
1125         __attribute__ ((format (printf, 3, 4)));
1126 extern void ext4_grp_locked_error(struct super_block *, ext4_group_t,
1127                                 const char *, const char *, ...)
1128         __attribute__ ((format (printf, 4, 5)));
1129 extern void ext4_update_dynamic_rev(struct super_block *sb);
1130 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1131                                         __u32 compat);
1132 extern int ext4_update_rocompat_feature(handle_t *handle,
1133                                         struct super_block *sb, __u32 rocompat);
1134 extern int ext4_update_incompat_feature(handle_t *handle,
1135                                         struct super_block *sb, __u32 incompat);
1136 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
1137                                       struct ext4_group_desc *bg);
1138 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
1139                                       struct ext4_group_desc *bg);
1140 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
1141                                      struct ext4_group_desc *bg);
1142 extern __u32 ext4_free_blks_count(struct super_block *sb,
1143                                 struct ext4_group_desc *bg);
1144 extern __u32 ext4_free_inodes_count(struct super_block *sb,
1145                                  struct ext4_group_desc *bg);
1146 extern __u32 ext4_used_dirs_count(struct super_block *sb,
1147                                 struct ext4_group_desc *bg);
1148 extern __u32 ext4_itable_unused_count(struct super_block *sb,
1149                                    struct ext4_group_desc *bg);
1150 extern void ext4_block_bitmap_set(struct super_block *sb,
1151                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1152 extern void ext4_inode_bitmap_set(struct super_block *sb,
1153                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1154 extern void ext4_inode_table_set(struct super_block *sb,
1155                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
1156 extern void ext4_free_blks_set(struct super_block *sb,
1157                                struct ext4_group_desc *bg, __u32 count);
1158 extern void ext4_free_inodes_set(struct super_block *sb,
1159                                 struct ext4_group_desc *bg, __u32 count);
1160 extern void ext4_used_dirs_set(struct super_block *sb,
1161                                 struct ext4_group_desc *bg, __u32 count);
1162 extern void ext4_itable_unused_set(struct super_block *sb,
1163                                    struct ext4_group_desc *bg, __u32 count);
1164
1165 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
1166 {
1167         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
1168                 le32_to_cpu(es->s_blocks_count_lo);
1169 }
1170
1171 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
1172 {
1173         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
1174                 le32_to_cpu(es->s_r_blocks_count_lo);
1175 }
1176
1177 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
1178 {
1179         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
1180                 le32_to_cpu(es->s_free_blocks_count_lo);
1181 }
1182
1183 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
1184                                          ext4_fsblk_t blk)
1185 {
1186         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
1187         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
1188 }
1189
1190 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
1191                                               ext4_fsblk_t blk)
1192 {
1193         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
1194         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
1195 }
1196
1197 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
1198                                            ext4_fsblk_t blk)
1199 {
1200         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
1201         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
1202 }
1203
1204 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
1205 {
1206         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
1207                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
1208                         le32_to_cpu(raw_inode->i_size_lo);
1209         else
1210                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
1211 }
1212
1213 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
1214 {
1215         raw_inode->i_size_lo = cpu_to_le32(i_size);
1216         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
1217 }
1218
1219 static inline
1220 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
1221                                             ext4_group_t group)
1222 {
1223          struct ext4_group_info ***grp_info;
1224          long indexv, indexh;
1225          grp_info = EXT4_SB(sb)->s_group_info;
1226          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
1227          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
1228          return grp_info[indexv][indexh];
1229 }
1230
1231
1232 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
1233                                              ext4_group_t block_group)
1234 {
1235         return block_group >> sbi->s_log_groups_per_flex;
1236 }
1237
1238 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
1239 {
1240         return 1 << sbi->s_log_groups_per_flex;
1241 }
1242
1243 #define ext4_std_error(sb, errno)                               \
1244 do {                                                            \
1245         if ((errno))                                            \
1246                 __ext4_std_error((sb), __func__, (errno));      \
1247 } while (0)
1248
1249 #ifdef CONFIG_SMP
1250 /* Each CPU can accumulate percpu_counter_batch blocks in their local
1251  * counters. So we need to make sure we have free blocks more
1252  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
1253  */
1254 #define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
1255 #else
1256 #define EXT4_FREEBLOCKS_WATERMARK 0
1257 #endif
1258
1259 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
1260 {
1261         /*
1262          * XXX: replace with spinlock if seen contended -bzzz
1263          */
1264         down_write(&EXT4_I(inode)->i_data_sem);
1265         if (newsize > EXT4_I(inode)->i_disksize)
1266                 EXT4_I(inode)->i_disksize = newsize;
1267         up_write(&EXT4_I(inode)->i_data_sem);
1268         return ;
1269 }
1270
1271 struct ext4_group_info {
1272         unsigned long   bb_state;
1273         struct rb_root  bb_free_root;
1274         unsigned short  bb_first_free;
1275         unsigned short  bb_free;
1276         unsigned short  bb_fragments;
1277         struct          list_head bb_prealloc_list;
1278 #ifdef DOUBLE_CHECK
1279         void            *bb_bitmap;
1280 #endif
1281         struct rw_semaphore alloc_sem;
1282         unsigned short  bb_counters[];
1283 };
1284
1285 #define EXT4_GROUP_INFO_NEED_INIT_BIT   0
1286 #define EXT4_GROUP_INFO_LOCKED_BIT      1
1287
1288 #define EXT4_MB_GRP_NEED_INIT(grp)      \
1289         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
1290
1291 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
1292 {
1293         struct ext4_group_info *grinfo = ext4_get_group_info(sb, group);
1294
1295         bit_spin_lock(EXT4_GROUP_INFO_LOCKED_BIT, &(grinfo->bb_state));
1296 }
1297
1298 static inline void ext4_unlock_group(struct super_block *sb,
1299                                         ext4_group_t group)
1300 {
1301         struct ext4_group_info *grinfo = ext4_get_group_info(sb, group);
1302
1303         bit_spin_unlock(EXT4_GROUP_INFO_LOCKED_BIT, &(grinfo->bb_state));
1304 }
1305
1306 static inline int ext4_is_group_locked(struct super_block *sb,
1307                                         ext4_group_t group)
1308 {
1309         struct ext4_group_info *grinfo = ext4_get_group_info(sb, group);
1310
1311         return bit_spin_is_locked(EXT4_GROUP_INFO_LOCKED_BIT,
1312                                                 &(grinfo->bb_state));
1313 }
1314
1315 /*
1316  * Inodes and files operations
1317  */
1318
1319 /* dir.c */
1320 extern const struct file_operations ext4_dir_operations;
1321
1322 /* file.c */
1323 extern const struct inode_operations ext4_file_inode_operations;
1324 extern const struct file_operations ext4_file_operations;
1325
1326 /* namei.c */
1327 extern const struct inode_operations ext4_dir_inode_operations;
1328 extern const struct inode_operations ext4_special_inode_operations;
1329
1330 /* symlink.c */
1331 extern const struct inode_operations ext4_symlink_inode_operations;
1332 extern const struct inode_operations ext4_fast_symlink_inode_operations;
1333
1334 /* extents.c */
1335 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
1336 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
1337 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
1338                                        int chunk);
1339 extern int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
1340                                ext4_lblk_t iblock, unsigned int max_blocks,
1341                                struct buffer_head *bh_result,
1342                                int create, int extend_disksize);
1343 extern void ext4_ext_truncate(struct inode *);
1344 extern void ext4_ext_init(struct super_block *);
1345 extern void ext4_ext_release(struct super_block *);
1346 extern long ext4_fallocate(struct inode *inode, int mode, loff_t offset,
1347                           loff_t len);
1348 extern int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode,
1349                         sector_t block, unsigned int max_blocks,
1350                         struct buffer_head *bh, int create,
1351                         int extend_disksize, int flag);
1352 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1353                         __u64 start, __u64 len);
1354
1355 /*
1356  * Add new method to test wether block and inode bitmaps are properly
1357  * initialized. With uninit_bg reading the block from disk is not enough
1358  * to mark the bitmap uptodate. We need to also zero-out the bitmap
1359  */
1360 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
1361
1362 static inline int bitmap_uptodate(struct buffer_head *bh)
1363 {
1364         return (buffer_uptodate(bh) &&
1365                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
1366 }
1367 static inline void set_bitmap_uptodate(struct buffer_head *bh)
1368 {
1369         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
1370 }
1371
1372 #endif  /* __KERNEL__ */
1373
1374 #endif  /* _EXT4_H */