fs/ext4/ext4.h

   1 /*
   2  *  ext4.h
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/include/linux/minix_fs.h
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  */
  15
  16 #ifndef _EXT4_H
  17 #define _EXT4_H
  18
  19 #include <linux/types.h>
  20 #include <linux/blkdev.h>
  21 #include <linux/magic.h>
  22 #include <linux/jbd2.h>
  23 #include <linux/quota.h>
  24 #include <linux/rwsem.h>
  25 #include <linux/rbtree.h>
  26 #include <linux/seqlock.h>
  27 #include <linux/mutex.h>
  28 #include <linux/timer.h>
  29 #include <linux/wait.h>
  30 #include <linux/blockgroup_lock.h>
  31 #include <linux/percpu_counter.h>
  32
  33 /*
  34  * The fourth extended filesystem constants/structures
  35  */
  36
  37 /*
  38  * Define EXT4FS_DEBUG to produce debug messages
  39  */
  40 #undef EXT4FS_DEBUG
  41
  42 /*
  43  * Debug code
  44  */
  45 #ifdef EXT4FS_DEBUG
  46 #define ext4_debug(f, a...)                                             \
  47         do {                                                            \
  48                 printk(KERN_DEBUG "EXT4-fs DEBUG (%s, %d): %s:",        \
  49                         __FILE__, __LINE__, __func__);                  \
  50                 printk(KERN_DEBUG f, ## a);                             \
  51         } while (0)
  52 #else
  53 #define ext4_debug(f, a...)     do {} while (0)
  54 #endif
  55
  56 /* data type for block offset of block group */
  57 typedef int ext4_grpblk_t;
  58
  59 /* data type for filesystem-wide blocks number */
  60 typedef unsigned long long ext4_fsblk_t;
  61
  62 /* data type for file logical block number */
  63 typedef __u32 ext4_lblk_t;
  64
  65 /* data type for block group number */
  66 typedef unsigned int ext4_group_t;
  67
  68 /*
  69  * Flags used in mballoc's allocation_context flags field.
  70  *
  71  * Also used to show what's going on for debugging purposes when the
  72  * flag field is exported via the traceport interface
  73  */
  74
  75 /* prefer goal again. length */
  76 #define EXT4_MB_HINT_MERGE              0x0001
  77 /* blocks already reserved */
  78 #define EXT4_MB_HINT_RESERVED           0x0002
  79 /* metadata is being allocated */
  80 #define EXT4_MB_HINT_METADATA           0x0004
  81 /* first blocks in the file */
  82 #define EXT4_MB_HINT_FIRST              0x0008
  83 /* search for the best chunk */
  84 #define EXT4_MB_HINT_BEST               0x0010
  85 /* data is being allocated */
  86 #define EXT4_MB_HINT_DATA               0x0020
  87 /* don't preallocate (for tails) */
  88 #define EXT4_MB_HINT_NOPREALLOC         0x0040
  89 /* allocate for locality group */
  90 #define EXT4_MB_HINT_GROUP_ALLOC        0x0080
  91 /* allocate goal blocks or none */
  92 #define EXT4_MB_HINT_GOAL_ONLY          0x0100
  93 /* goal is meaningful */
  94 #define EXT4_MB_HINT_TRY_GOAL           0x0200
  95 /* blocks already pre-reserved by delayed allocation */
  96 #define EXT4_MB_DELALLOC_RESERVED       0x0400
  97 /* We are doing stream allocation */
  98 #define EXT4_MB_STREAM_ALLOC            0x0800
  99
 100
 101 struct ext4_allocation_request {
 102         /* target inode for block we're allocating */
 103         struct inode *inode;
 104         /* how many blocks we want to allocate */
 105         unsigned int len;
 106         /* logical block in target inode */
 107         ext4_lblk_t logical;
 108         /* the closest logical allocated block to the left */
 109         ext4_lblk_t lleft;
 110         /* the closest logical allocated block to the right */
 111         ext4_lblk_t lright;
 112         /* phys. target (a hint) */
 113         ext4_fsblk_t goal;
 114         /* phys. block for the closest logical allocated block to the left */
 115         ext4_fsblk_t pleft;
 116         /* phys. block for the closest logical allocated block to the right */
 117         ext4_fsblk_t pright;
 118         /* flags. see above EXT4_MB_HINT_* */
 119         unsigned int flags;
 120 };
 121
 122 /*
 123  * For delayed allocation tracking
 124  */
 125 struct mpage_da_data {
 126         struct inode *inode;
 127         sector_t b_blocknr;             /* start block number of extent */
 128         size_t b_size;                  /* size of extent */
 129         unsigned long b_state;          /* state of the extent */
 130         unsigned long first_page, next_page;    /* extent of pages */
 131         struct writeback_control *wbc;
 132         int io_done;
 133         int pages_written;
 134         int retval;
 135 };
 136 #define DIO_AIO_UNWRITTEN       0x1
 137 typedef struct ext4_io_end {
 138         struct list_head        list;           /* per-file finished AIO list */
 139         struct inode            *inode;         /* file being written to */
 140         unsigned int            flag;           /* unwritten or not */
 141         int                     error;          /* I/O error code */
 142         loff_t                  offset;         /* offset in the file */
 143         ssize_t                 size;           /* size of the extent */
 144         struct work_struct      work;           /* data work queue */
 145 } ext4_io_end_t;
 146
 147 /*
 148  * Special inodes numbers
 149  */
 150 #define EXT4_BAD_INO             1      /* Bad blocks inode */
 151 #define EXT4_ROOT_INO            2      /* Root inode */
 152 #define EXT4_BOOT_LOADER_INO     5      /* Boot loader inode */
 153 #define EXT4_UNDEL_DIR_INO       6      /* Undelete directory inode */
 154 #define EXT4_RESIZE_INO          7      /* Reserved group descriptors inode */
 155 #define EXT4_JOURNAL_INO         8      /* Journal inode */
 156
 157 /* First non-reserved inode for old ext4 filesystems */
 158 #define EXT4_GOOD_OLD_FIRST_INO 11
 159
 160 /*
 161  * Maximal count of links to a file
 162  */
 163 #define EXT4_LINK_MAX           65000
 164
 165 /*
 166  * Macro-instructions used to manage several block sizes
 167  */
 168 #define EXT4_MIN_BLOCK_SIZE             1024
 169 #define EXT4_MAX_BLOCK_SIZE             65536
 170 #define EXT4_MIN_BLOCK_LOG_SIZE         10
 171 #ifdef __KERNEL__
 172 # define EXT4_BLOCK_SIZE(s)             ((s)->s_blocksize)
 173 #else
 174 # define EXT4_BLOCK_SIZE(s)             (EXT4_MIN_BLOCK_SIZE << (s)->s_log_block_size)
 175 #endif
 176 #define EXT4_ADDR_PER_BLOCK(s)          (EXT4_BLOCK_SIZE(s) / sizeof(__u32))
 177 #ifdef __KERNEL__
 178 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_blocksize_bits)
 179 #else
 180 # define EXT4_BLOCK_SIZE_BITS(s)        ((s)->s_log_block_size + 10)
 181 #endif
 182 #ifdef __KERNEL__
 183 #define EXT4_ADDR_PER_BLOCK_BITS(s)     (EXT4_SB(s)->s_addr_per_block_bits)
 184 #define EXT4_INODE_SIZE(s)              (EXT4_SB(s)->s_inode_size)
 185 #define EXT4_FIRST_INO(s)               (EXT4_SB(s)->s_first_ino)
 186 #else
 187 #define EXT4_INODE_SIZE(s)      (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 188                                  EXT4_GOOD_OLD_INODE_SIZE : \
 189                                  (s)->s_inode_size)
 190 #define EXT4_FIRST_INO(s)       (((s)->s_rev_level == EXT4_GOOD_OLD_REV) ? \
 191                                  EXT4_GOOD_OLD_FIRST_INO : \
 192                                  (s)->s_first_ino)
 193 #endif
 194 #define EXT4_BLOCK_ALIGN(size, blkbits)         ALIGN((size), (1 << (blkbits)))
 195
 196 /*
 197  * Structure of a blocks group descriptor
 198  */
 199 struct ext4_group_desc
 200 {
 201         __le32  bg_block_bitmap_lo;     /* Blocks bitmap block */
 202         __le32  bg_inode_bitmap_lo;     /* Inodes bitmap block */
 203         __le32  bg_inode_table_lo;      /* Inodes table block */
 204         __le16  bg_free_blocks_count_lo;/* Free blocks count */
 205         __le16  bg_free_inodes_count_lo;/* Free inodes count */
 206         __le16  bg_used_dirs_count_lo;  /* Directories count */
 207         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
 208         __u32   bg_reserved[2];         /* Likely block/inode bitmap checksum */
 209         __le16  bg_itable_unused_lo;    /* Unused inodes count */
 210         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
 211         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
 212         __le32  bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
 213         __le32  bg_inode_table_hi;      /* Inodes table block MSB */
 214         __le16  bg_free_blocks_count_hi;/* Free blocks count MSB */
 215         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
 216         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
 217         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
 218         __u32   bg_reserved2[3];
 219 };
 220
 221 /*
 222  * Structure of a flex block group info
 223  */
 224
 225 struct flex_groups {
 226         atomic_t free_inodes;
 227         atomic_t free_blocks;
 228         atomic_t used_dirs;
 229 };
 230
 231 #define EXT4_BG_INODE_UNINIT    0x0001 /* Inode table/bitmap not in use */
 232 #define EXT4_BG_BLOCK_UNINIT    0x0002 /* Block bitmap not in use */
 233 #define EXT4_BG_INODE_ZEROED    0x0004 /* On-disk itable initialized to zero */
 234
 235 /*
 236  * Macro-instructions used to manage group descriptors
 237  */
 238 #define EXT4_MIN_DESC_SIZE              32
 239 #define EXT4_MIN_DESC_SIZE_64BIT        64
 240 #define EXT4_MAX_DESC_SIZE              EXT4_MIN_BLOCK_SIZE
 241 #define EXT4_DESC_SIZE(s)               (EXT4_SB(s)->s_desc_size)
 242 #ifdef __KERNEL__
 243 # define EXT4_BLOCKS_PER_GROUP(s)       (EXT4_SB(s)->s_blocks_per_group)
 244 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_SB(s)->s_desc_per_block)
 245 # define EXT4_INODES_PER_GROUP(s)       (EXT4_SB(s)->s_inodes_per_group)
 246 # define EXT4_DESC_PER_BLOCK_BITS(s)    (EXT4_SB(s)->s_desc_per_block_bits)
 247 #else
 248 # define EXT4_BLOCKS_PER_GROUP(s)       ((s)->s_blocks_per_group)
 249 # define EXT4_DESC_PER_BLOCK(s)         (EXT4_BLOCK_SIZE(s) / EXT4_DESC_SIZE(s))
 250 # define EXT4_INODES_PER_GROUP(s)       ((s)->s_inodes_per_group)
 251 #endif
 252
 253 /*
 254  * Constants relative to the data blocks
 255  */
 256 #define EXT4_NDIR_BLOCKS                12
 257 #define EXT4_IND_BLOCK                  EXT4_NDIR_BLOCKS
 258 #define EXT4_DIND_BLOCK                 (EXT4_IND_BLOCK + 1)
 259 #define EXT4_TIND_BLOCK                 (EXT4_DIND_BLOCK + 1)
 260 #define EXT4_N_BLOCKS                   (EXT4_TIND_BLOCK + 1)
 261
 262 /*
 263  * Inode flags
 264  */
 265 #define EXT4_SECRM_FL                   0x00000001 /* Secure deletion */
 266 #define EXT4_UNRM_FL                    0x00000002 /* Undelete */
 267 #define EXT4_COMPR_FL                   0x00000004 /* Compress file */
 268 #define EXT4_SYNC_FL                    0x00000008 /* Synchronous updates */
 269 #define EXT4_IMMUTABLE_FL               0x00000010 /* Immutable file */
 270 #define EXT4_APPEND_FL                  0x00000020 /* writes to file may only append */
 271 #define EXT4_NODUMP_FL                  0x00000040 /* do not dump file */
 272 #define EXT4_NOATIME_FL                 0x00000080 /* do not update atime */
 273 /* Reserved for compression usage... */
 274 #define EXT4_DIRTY_FL                   0x00000100
 275 #define EXT4_COMPRBLK_FL                0x00000200 /* One or more compressed clusters */
 276 #define EXT4_NOCOMPR_FL                 0x00000400 /* Don't compress */
 277 #define EXT4_ECOMPR_FL                  0x00000800 /* Compression error */
 278 /* End compression flags --- maybe not all used */
 279 #define EXT4_INDEX_FL                   0x00001000 /* hash-indexed directory */
 280 #define EXT4_IMAGIC_FL                  0x00002000 /* AFS directory */
 281 #define EXT4_JOURNAL_DATA_FL            0x00004000 /* file data should be journaled */
 282 #define EXT4_NOTAIL_FL                  0x00008000 /* file tail should not be merged */
 283 #define EXT4_DIRSYNC_FL                 0x00010000 /* dirsync behaviour (directories only) */
 284 #define EXT4_TOPDIR_FL                  0x00020000 /* Top of directory hierarchies*/
 285 #define EXT4_HUGE_FILE_FL               0x00040000 /* Set to each huge file */
 286 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 287 #define EXT4_EA_INODE_FL                0x00200000 /* Inode used for large EA */
 288 #define EXT4_RESERVED_FL                0x80000000 /* reserved for ext4 lib */
 289
 290 #define EXT4_FL_USER_VISIBLE            0x000BDFFF /* User visible flags */
 291 #define EXT4_FL_USER_MODIFIABLE         0x000B80FF /* User modifiable flags */
 292
 293 /* Flags that should be inherited by new inodes from their parent. */
 294 #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
 295                            EXT4_SYNC_FL | EXT4_IMMUTABLE_FL | EXT4_APPEND_FL |\
 296                            EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
 297                            EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\
 298                            EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL)
 299
 300 /* Flags that are appropriate for regular files (all but dir-specific ones). */
 301 #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL))
 302
 303 /* Flags that are appropriate for non-directories/regular files. */
 304 #define EXT4_OTHER_FLMASK (EXT4_NODUMP_FL | EXT4_NOATIME_FL)
 305
 306 /* Mask out flags that are inappropriate for the given type of inode. */
 307 static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
 308 {
 309         if (S_ISDIR(mode))
 310                 return flags;
 311         else if (S_ISREG(mode))
 312                 return flags & EXT4_REG_FLMASK;
 313         else
 314                 return flags & EXT4_OTHER_FLMASK;
 315 }
 316
 317 /* Used to pass group descriptor data when online resize is done */
 318 struct ext4_new_group_input {
 319         __u32 group;            /* Group number for this data */
 320         __u64 block_bitmap;     /* Absolute block number of block bitmap */
 321         __u64 inode_bitmap;     /* Absolute block number of inode bitmap */
 322         __u64 inode_table;      /* Absolute block number of inode table start */
 323         __u32 blocks_count;     /* Total number of blocks in this group */
 324         __u16 reserved_blocks;  /* Number of reserved blocks in this group */
 325         __u16 unused;
 326 };
 327
 328 /* The struct ext4_new_group_input in kernel space, with free_blocks_count */
 329 struct ext4_new_group_data {
 330         __u32 group;
 331         __u64 block_bitmap;
 332         __u64 inode_bitmap;
 333         __u64 inode_table;
 334         __u32 blocks_count;
 335         __u16 reserved_blocks;
 336         __u16 unused;
 337         __u32 free_blocks_count;
 338 };
 339
 340 /*
 341  * Flags used by ext4_get_blocks()
 342  */
 343         /* Allocate any needed blocks and/or convert an unitialized
 344            extent to be an initialized ext4 */
 345 #define EXT4_GET_BLOCKS_CREATE                  0x0001
 346         /* Request the creation of an unitialized extent */
 347 #define EXT4_GET_BLOCKS_UNINIT_EXT              0x0002
 348 #define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT       (EXT4_GET_BLOCKS_UNINIT_EXT|\
 349                                                  EXT4_GET_BLOCKS_CREATE)
 350         /* Caller is from the delayed allocation writeout path,
 351            so set the magic i_delalloc_reserve_flag after taking the
 352            inode allocation semaphore for */
 353 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE        0x0004
 354         /* caller is from the direct IO path, request to creation of an
 355         unitialized extents if not allocated, split the uninitialized
 356         extent if blocks has been preallocated already*/
 357 #define EXT4_GET_BLOCKS_DIO                     0x0008
 358 #define EXT4_GET_BLOCKS_CONVERT                 0x0010
 359 #define EXT4_GET_BLOCKS_DIO_CREATE_EXT          (EXT4_GET_BLOCKS_DIO|\
 360                                          EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
 361         /* Convert extent to initialized after direct IO complete */
 362 #define EXT4_GET_BLOCKS_DIO_CONVERT_EXT         (EXT4_GET_BLOCKS_CONVERT|\
 363                                          EXT4_GET_BLOCKS_DIO_CREATE_EXT)
 364
 365 /*
 366  * Flags used by ext4_free_blocks
 367  */
 368 #define EXT4_FREE_BLOCKS_METADATA       0x0001
 369 #define EXT4_FREE_BLOCKS_FORGET         0x0002
 370 #define EXT4_FREE_BLOCKS_VALIDATED      0x0004
 371
 372 /*
 373  * ioctl commands
 374  */
 375 #define EXT4_IOC_GETFLAGS               FS_IOC_GETFLAGS
 376 #define EXT4_IOC_SETFLAGS               FS_IOC_SETFLAGS
 377 #define EXT4_IOC_GETVERSION             _IOR('f', 3, long)
 378 #define EXT4_IOC_SETVERSION             _IOW('f', 4, long)
 379 #define EXT4_IOC_GETVERSION_OLD         FS_IOC_GETVERSION
 380 #define EXT4_IOC_SETVERSION_OLD         FS_IOC_SETVERSION
 381 #ifdef CONFIG_JBD2_DEBUG
 382 #define EXT4_IOC_WAIT_FOR_READONLY      _IOR('f', 99, long)
 383 #endif
 384 #define EXT4_IOC_GETRSVSZ               _IOR('f', 5, long)
 385 #define EXT4_IOC_SETRSVSZ               _IOW('f', 6, long)
 386 #define EXT4_IOC_GROUP_EXTEND           _IOW('f', 7, unsigned long)
 387 #define EXT4_IOC_GROUP_ADD              _IOW('f', 8, struct ext4_new_group_input)
 388 #define EXT4_IOC_MIGRATE                _IO('f', 9)
 389  /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */
 390  /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */
 391 #define EXT4_IOC_ALLOC_DA_BLKS          _IO('f', 12)
 392 #define EXT4_IOC_MOVE_EXT               _IOWR('f', 15, struct move_extent)
 393
 394 /*
 395  * ioctl commands in 32 bit emulation
 396  */
 397 #define EXT4_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
 398 #define EXT4_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
 399 #define EXT4_IOC32_GETVERSION           _IOR('f', 3, int)
 400 #define EXT4_IOC32_SETVERSION           _IOW('f', 4, int)
 401 #define EXT4_IOC32_GETRSVSZ             _IOR('f', 5, int)
 402 #define EXT4_IOC32_SETRSVSZ             _IOW('f', 6, int)
 403 #define EXT4_IOC32_GROUP_EXTEND         _IOW('f', 7, unsigned int)
 404 #ifdef CONFIG_JBD2_DEBUG
 405 #define EXT4_IOC32_WAIT_FOR_READONLY    _IOR('f', 99, int)
 406 #endif
 407 #define EXT4_IOC32_GETVERSION_OLD       FS_IOC32_GETVERSION
 408 #define EXT4_IOC32_SETVERSION_OLD       FS_IOC32_SETVERSION
 409
 410
 411 /*
 412  *  Mount options
 413  */
 414 struct ext4_mount_options {
 415         unsigned long s_mount_opt;
 416         uid_t s_resuid;
 417         gid_t s_resgid;
 418         unsigned long s_commit_interval;
 419         u32 s_min_batch_time, s_max_batch_time;
 420 #ifdef CONFIG_QUOTA
 421         int s_jquota_fmt;
 422         char *s_qf_names[MAXQUOTAS];
 423 #endif
 424 };
 425
 426 /* Max physical block we can addres w/o extents */
 427 #define EXT4_MAX_BLOCK_FILE_PHYS        0xFFFFFFFF
 428
 429 /*
 430  * Structure of an inode on the disk
 431  */
 432 struct ext4_inode {
 433         __le16  i_mode;         /* File mode */
 434         __le16  i_uid;          /* Low 16 bits of Owner Uid */
 435         __le32  i_size_lo;      /* Size in bytes */
 436         __le32  i_atime;        /* Access time */
 437         __le32  i_ctime;        /* Inode Change time */
 438         __le32  i_mtime;        /* Modification time */
 439         __le32  i_dtime;        /* Deletion Time */
 440         __le16  i_gid;          /* Low 16 bits of Group Id */
 441         __le16  i_links_count;  /* Links count */
 442         __le32  i_blocks_lo;    /* Blocks count */
 443         __le32  i_flags;        /* File flags */
 444         union {
 445                 struct {
 446                         __le32  l_i_version;
 447                 } linux1;
 448                 struct {
 449                         __u32  h_i_translator;
 450                 } hurd1;
 451                 struct {
 452                         __u32  m_i_reserved1;
 453                 } masix1;
 454         } osd1;                         /* OS dependent 1 */
 455         __le32  i_block[EXT4_N_BLOCKS];/* Pointers to blocks */
 456         __le32  i_generation;   /* File version (for NFS) */
 457         __le32  i_file_acl_lo;  /* File ACL */
 458         __le32  i_size_high;
 459         __le32  i_obso_faddr;   /* Obsoleted fragment address */
 460         union {
 461                 struct {
 462                         __le16  l_i_blocks_high; /* were l_i_reserved1 */
 463                         __le16  l_i_file_acl_high;
 464                         __le16  l_i_uid_high;   /* these 2 fields */
 465                         __le16  l_i_gid_high;   /* were reserved2[0] */
 466                         __u32   l_i_reserved2;
 467                 } linux2;
 468                 struct {
 469                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 470                         __u16   h_i_mode_high;
 471                         __u16   h_i_uid_high;
 472                         __u16   h_i_gid_high;
 473                         __u32   h_i_author;
 474                 } hurd2;
 475                 struct {
 476                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
 477                         __le16  m_i_file_acl_high;
 478                         __u32   m_i_reserved2[2];
 479                 } masix2;
 480         } osd2;                         /* OS dependent 2 */
 481         __le16  i_extra_isize;
 482         __le16  i_pad1;
 483         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
 484         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
 485         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
 486         __le32  i_crtime;       /* File Creation time */
 487         __le32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
 488         __le32  i_version_hi;   /* high 32 bits for 64-bit version */
 489 };
 490
 491 struct move_extent {
 492         __u32 reserved;         /* should be zero */
 493         __u32 donor_fd;         /* donor file descriptor */
 494         __u64 orig_start;       /* logical start offset in block for orig */
 495         __u64 donor_start;      /* logical start offset in block for donor */
 496         __u64 len;              /* block length to be moved */
 497         __u64 moved_len;        /* moved block length */
 498 };
 499
 500 #define EXT4_EPOCH_BITS 2
 501 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
 502 #define EXT4_NSEC_MASK  (~0UL << EXT4_EPOCH_BITS)
 503
 504 /*
 505  * Extended fields will fit into an inode if the filesystem was formatted
 506  * with large inodes (-I 256 or larger) and there are not currently any EAs
 507  * consuming all of the available space. For new inodes we always reserve
 508  * enough space for the kernel's known extended fields, but for inodes
 509  * created with an old kernel this might not have been the case. None of
 510  * the extended inode fields is critical for correct filesystem operation.
 511  * This macro checks if a certain field fits in the inode. Note that
 512  * inode-size = GOOD_OLD_INODE_SIZE + i_extra_isize
 513  */
 514 #define EXT4_FITS_IN_INODE(ext4_inode, einode, field)   \
 515         ((offsetof(typeof(*ext4_inode), field) +        \
 516           sizeof((ext4_inode)->field))                  \
 517         <= (EXT4_GOOD_OLD_INODE_SIZE +                  \
 518             (einode)->i_extra_isize))                   \
 519
 520 static inline __le32 ext4_encode_extra_time(struct timespec *time)
 521 {
 522        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
 523                            (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
 524                           ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
 525 }
 526
 527 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
 528 {
 529        if (sizeof(time->tv_sec) > 4)
 530                time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 531                                << 32;
 532        time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 533 }
 534
 535 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)                          \
 536 do {                                                                           \
 537         (raw_inode)->xtime = cpu_to_le32((inode)->xtime.tv_sec);               \
 538         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 539                 (raw_inode)->xtime ## _extra =                                 \
 540                                 ext4_encode_extra_time(&(inode)->xtime);       \
 541 } while (0)
 542
 543 #define EXT4_EINODE_SET_XTIME(xtime, einode, raw_inode)                        \
 544 do {                                                                           \
 545         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 546                 (raw_inode)->xtime = cpu_to_le32((einode)->xtime.tv_sec);      \
 547         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 548                 (raw_inode)->xtime ## _extra =                                 \
 549                                 ext4_encode_extra_time(&(einode)->xtime);      \
 550 } while (0)
 551
 552 #define EXT4_INODE_GET_XTIME(xtime, inode, raw_inode)                          \
 553 do {                                                                           \
 554         (inode)->xtime.tv_sec = (signed)le32_to_cpu((raw_inode)->xtime);       \
 555         if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), xtime ## _extra))     \
 556                 ext4_decode_extra_time(&(inode)->xtime,                        \
 557                                        raw_inode->xtime ## _extra);            \
 558 } while (0)
 559
 560 #define EXT4_EINODE_GET_XTIME(xtime, einode, raw_inode)                        \
 561 do {                                                                           \
 562         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime))                      \
 563                 (einode)->xtime.tv_sec =                                       \
 564                         (signed)le32_to_cpu((raw_inode)->xtime);               \
 565         if (EXT4_FITS_IN_INODE(raw_inode, einode, xtime ## _extra))            \
 566                 ext4_decode_extra_time(&(einode)->xtime,                       \
 567                                        raw_inode->xtime ## _extra);            \
 568 } while (0)
 569
 570 #define i_disk_version osd1.linux1.l_i_version
 571
 572 #if defined(__KERNEL__) || defined(__linux__)
 573 #define i_reserved1     osd1.linux1.l_i_reserved1
 574 #define i_file_acl_high osd2.linux2.l_i_file_acl_high
 575 #define i_blocks_high   osd2.linux2.l_i_blocks_high
 576 #define i_uid_low       i_uid
 577 #define i_gid_low       i_gid
 578 #define i_uid_high      osd2.linux2.l_i_uid_high
 579 #define i_gid_high      osd2.linux2.l_i_gid_high
 580 #define i_reserved2     osd2.linux2.l_i_reserved2
 581
 582 #elif defined(__GNU__)
 583
 584 #define i_translator    osd1.hurd1.h_i_translator
 585 #define i_uid_high      osd2.hurd2.h_i_uid_high
 586 #define i_gid_high      osd2.hurd2.h_i_gid_high
 587 #define i_author        osd2.hurd2.h_i_author
 588
 589 #elif defined(__masix__)
 590
 591 #define i_reserved1     osd1.masix1.m_i_reserved1
 592 #define i_file_acl_high osd2.masix2.m_i_file_acl_high
 593 #define i_reserved2     osd2.masix2.m_i_reserved2
 594
 595 #endif /* defined(__KERNEL__) || defined(__linux__) */
 596
 597 /*
 598  * storage for cached extent
 599  */
 600 struct ext4_ext_cache {
 601         ext4_fsblk_t    ec_start;
 602         ext4_lblk_t     ec_block;
 603         __u32           ec_len; /* must be 32bit to return holes */
 604         __u32           ec_type;
 605 };
 606
 607 /*
 608  * fourth extended file system inode data in memory
 609  */
 610 struct ext4_inode_info {
 611         __le32  i_data[15];     /* unconverted */
 612         __u32   i_flags;
 613         ext4_fsblk_t    i_file_acl;
 614         __u32   i_dtime;
 615
 616         /*
 617          * i_block_group is the number of the block group which contains
 618          * this file's inode.  Constant across the lifetime of the inode,
 619          * it is ued for making block allocation decisions - we try to
 620          * place a file's data blocks near its inode block, and new inodes
 621          * near to their parent directory's inode.
 622          */
 623         ext4_group_t    i_block_group;
 624         unsigned long   i_state_flags;          /* Dynamic state flags */
 625
 626         ext4_lblk_t             i_dir_start_lookup;
 627 #ifdef CONFIG_EXT4_FS_XATTR
 628         /*
 629          * Extended attributes can be read independently of the main file
 630          * data. Taking i_mutex even when reading would cause contention
 631          * between readers of EAs and writers of regular file data, so
 632          * instead we synchronize on xattr_sem when reading or changing
 633          * EAs.
 634          */
 635         struct rw_semaphore xattr_sem;
 636 #endif
 637
 638         struct list_head i_orphan;      /* unlinked but open inodes */
 639
 640         /*
 641          * i_disksize keeps track of what the inode size is ON DISK, not
 642          * in memory.  During truncate, i_size is set to the new size by
 643          * the VFS prior to calling ext4_truncate(), but the filesystem won't
 644          * set i_disksize to 0 until the truncate is actually under way.
 645          *
 646          * The intent is that i_disksize always represents the blocks which
 647          * are used by this file.  This allows recovery to restart truncate
 648          * on orphans if we crash during truncate.  We actually write i_disksize
 649          * into the on-disk inode when writing inodes out, instead of i_size.
 650          *
 651          * The only time when i_disksize and i_size may be different is when
 652          * a truncate is in progress.  The only things which change i_disksize
 653          * are ext4_get_block (growth) and ext4_truncate (shrinkth).
 654          */
 655         loff_t  i_disksize;
 656
 657         /*
 658          * i_data_sem is for serialising ext4_truncate() against
 659          * ext4_getblock().  In the 2.4 ext2 design, great chunks of inode's
 660          * data tree are chopped off during truncate. We can't do that in
 661          * ext4 because whenever we perform intermediate commits during
 662          * truncate, the inode and all the metadata blocks *must* be in a
 663          * consistent state which allows truncation of the orphans to restart
 664          * during recovery.  Hence we must fix the get_block-vs-truncate race
 665          * by other means, so we have i_data_sem.
 666          */
 667         struct rw_semaphore i_data_sem;
 668         struct inode vfs_inode;
 669         struct jbd2_inode jinode;
 670
 671         struct ext4_ext_cache i_cached_extent;
 672         /*
 673          * File creation time. Its function is same as that of
 674          * struct timespec i_{a,c,m}time in the generic inode.
 675          */
 676         struct timespec i_crtime;
 677
 678         /* mballoc */
 679         struct list_head i_prealloc_list;
 680         spinlock_t i_prealloc_lock;
 681
 682         /* ialloc */
 683         ext4_group_t    i_last_alloc_group;
 684
 685         /* allocation reservation info for delalloc */
 686         unsigned int i_reserved_data_blocks;
 687         unsigned int i_reserved_meta_blocks;
 688         unsigned int i_allocated_meta_blocks;
 689         unsigned short i_delalloc_reserved_flag;
 690         sector_t i_da_metadata_calc_last_lblock;
 691         int i_da_metadata_calc_len;
 692
 693         /* on-disk additional length */
 694         __u16 i_extra_isize;
 695
 696         spinlock_t i_block_reservation_lock;
 697 #ifdef CONFIG_QUOTA
 698         /* quota space reservation, managed internally by quota code */
 699         qsize_t i_reserved_quota;
 700 #endif
 701
 702         /* completed async DIOs that might need unwritten extents handling */
 703         struct list_head i_aio_dio_complete_list;
 704         /* current io_end structure for async DIO write*/
 705         ext4_io_end_t *cur_aio_dio;
 706
 707         /*
 708          * Transactions that contain inode's metadata needed to complete
 709          * fsync and fdatasync, respectively.
 710          */
 711         tid_t i_sync_tid;
 712         tid_t i_datasync_tid;
 713 };
 714
 715 /*
 716  * File system states
 717  */
 718 #define EXT4_VALID_FS                   0x0001  /* Unmounted cleanly */
 719 #define EXT4_ERROR_FS                   0x0002  /* Errors detected */
 720 #define EXT4_ORPHAN_FS                  0x0004  /* Orphans being recovered */
 721
 722 /*
 723  * Misc. filesystem flags
 724  */
 725 #define EXT2_FLAGS_SIGNED_HASH          0x0001  /* Signed dirhash in use */
 726 #define EXT2_FLAGS_UNSIGNED_HASH        0x0002  /* Unsigned dirhash in use */
 727 #define EXT2_FLAGS_TEST_FILESYS         0x0004  /* to test development code */
 728
 729 /*
 730  * Mount flags
 731  */
 732 #define EXT4_MOUNT_OLDALLOC             0x00002  /* Don't use the new Orlov allocator */
 733 #define EXT4_MOUNT_GRPID                0x00004 /* Create files with directory's group */
 734 #define EXT4_MOUNT_DEBUG                0x00008 /* Some debugging messages */
 735 #define EXT4_MOUNT_ERRORS_CONT          0x00010 /* Continue on errors */
 736 #define EXT4_MOUNT_ERRORS_RO            0x00020 /* Remount fs ro on errors */
 737 #define EXT4_MOUNT_ERRORS_PANIC         0x00040 /* Panic on errors */
 738 #define EXT4_MOUNT_MINIX_DF             0x00080 /* Mimics the Minix statfs */
 739 #define EXT4_MOUNT_NOLOAD               0x00100 /* Don't use existing journal*/
 740 #define EXT4_MOUNT_DATA_FLAGS           0x00C00 /* Mode for data writes: */
 741 #define EXT4_MOUNT_JOURNAL_DATA         0x00400 /* Write data to journal */
 742 #define EXT4_MOUNT_ORDERED_DATA         0x00800 /* Flush data before commit */
 743 #define EXT4_MOUNT_WRITEBACK_DATA       0x00C00 /* No data ordering */
 744 #define EXT4_MOUNT_UPDATE_JOURNAL       0x01000 /* Update the journal format */
 745 #define EXT4_MOUNT_NO_UID32             0x02000  /* Disable 32-bit UIDs */
 746 #define EXT4_MOUNT_XATTR_USER           0x04000 /* Extended user attributes */
 747 #define EXT4_MOUNT_POSIX_ACL            0x08000 /* POSIX Access Control Lists */
 748 #define EXT4_MOUNT_NO_AUTO_DA_ALLOC     0x10000 /* No auto delalloc mapping */
 749 #define EXT4_MOUNT_BARRIER              0x20000 /* Use block barriers */
 750 #define EXT4_MOUNT_NOBH                 0x40000 /* No bufferheads */
 751 #define EXT4_MOUNT_QUOTA                0x80000 /* Some quota option set */
 752 #define EXT4_MOUNT_USRQUOTA             0x100000 /* "old" user quota */
 753 #define EXT4_MOUNT_GRPQUOTA             0x200000 /* "old" group quota */
 754 #define EXT4_MOUNT_JOURNAL_CHECKSUM     0x800000 /* Journal checksums */
 755 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */
 756 #define EXT4_MOUNT_I_VERSION            0x2000000 /* i_version support */
 757 #define EXT4_MOUNT_DELALLOC             0x8000000 /* Delalloc support */
 758 #define EXT4_MOUNT_DATA_ERR_ABORT       0x10000000 /* Abort on file data write */
 759 #define EXT4_MOUNT_BLOCK_VALIDITY       0x20000000 /* Block validity checking */
 760 #define EXT4_MOUNT_DISCARD              0x40000000 /* Issue DISCARD requests */
 761
 762 #define clear_opt(o, opt)               o &= ~EXT4_MOUNT_##opt
 763 #define set_opt(o, opt)                 o |= EXT4_MOUNT_##opt
 764 #define test_opt(sb, opt)               (EXT4_SB(sb)->s_mount_opt & \
 765                                          EXT4_MOUNT_##opt)
 766
 767 #define ext4_set_bit                    ext2_set_bit
 768 #define ext4_set_bit_atomic             ext2_set_bit_atomic
 769 #define ext4_clear_bit                  ext2_clear_bit
 770 #define ext4_clear_bit_atomic           ext2_clear_bit_atomic
 771 #define ext4_test_bit                   ext2_test_bit
 772 #define ext4_find_first_zero_bit        ext2_find_first_zero_bit
 773 #define ext4_find_next_zero_bit         ext2_find_next_zero_bit
 774 #define ext4_find_next_bit              ext2_find_next_bit
 775
 776 /*
 777  * Maximal mount counts between two filesystem checks
 778  */
 779 #define EXT4_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
 780 #define EXT4_DFL_CHECKINTERVAL          0       /* Don't use interval check */
 781
 782 /*
 783  * Behaviour when detecting errors
 784  */
 785 #define EXT4_ERRORS_CONTINUE            1       /* Continue execution */
 786 #define EXT4_ERRORS_RO                  2       /* Remount fs read-only */
 787 #define EXT4_ERRORS_PANIC               3       /* Panic */
 788 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
 789
 790 /*
 791  * Structure of the super block
 792  */
 793 struct ext4_super_block {
 794 /*00*/  __le32  s_inodes_count;         /* Inodes count */
 795         __le32  s_blocks_count_lo;      /* Blocks count */
 796         __le32  s_r_blocks_count_lo;    /* Reserved blocks count */
 797         __le32  s_free_blocks_count_lo; /* Free blocks count */
 798 /*10*/  __le32  s_free_inodes_count;    /* Free inodes count */
 799         __le32  s_first_data_block;     /* First Data Block */
 800         __le32  s_log_block_size;       /* Block size */
 801         __le32  s_obso_log_frag_size;   /* Obsoleted fragment size */
 802 /*20*/  __le32  s_blocks_per_group;     /* # Blocks per group */
 803         __le32  s_obso_frags_per_group; /* Obsoleted fragments per group */
 804         __le32  s_inodes_per_group;     /* # Inodes per group */
 805         __le32  s_mtime;                /* Mount time */
 806 /*30*/  __le32  s_wtime;                /* Write time */
 807         __le16  s_mnt_count;            /* Mount count */
 808         __le16  s_max_mnt_count;        /* Maximal mount count */
 809         __le16  s_magic;                /* Magic signature */
 810         __le16  s_state;                /* File system state */
 811         __le16  s_errors;               /* Behaviour when detecting errors */
 812         __le16  s_minor_rev_level;      /* minor revision level */
 813 /*40*/  __le32  s_lastcheck;            /* time of last check */
 814         __le32  s_checkinterval;        /* max. time between checks */
 815         __le32  s_creator_os;           /* OS */
 816         __le32  s_rev_level;            /* Revision level */
 817 /*50*/  __le16  s_def_resuid;           /* Default uid for reserved blocks */
 818         __le16  s_def_resgid;           /* Default gid for reserved blocks */
 819         /*
 820          * These fields are for EXT4_DYNAMIC_REV superblocks only.
 821          *
 822          * Note: the difference between the compatible feature set and
 823          * the incompatible feature set is that if there is a bit set
 824          * in the incompatible feature set that the kernel doesn't
 825          * know about, it should refuse to mount the filesystem.
 826          *
 827          * e2fsck's requirements are more strict; if it doesn't know
 828          * about a feature in either the compatible or incompatible
 829          * feature set, it must abort and not try to meddle with
 830          * things it doesn't understand...
 831          */
 832         __le32  s_first_ino;            /* First non-reserved inode */
 833         __le16  s_inode_size;           /* size of inode structure */
 834         __le16  s_block_group_nr;       /* block group # of this superblock */
 835         __le32  s_feature_compat;       /* compatible feature set */
 836 /*60*/  __le32  s_feature_incompat;     /* incompatible feature set */
 837         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
 838 /*68*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
 839 /*78*/  char    s_volume_name[16];      /* volume name */
 840 /*88*/  char    s_last_mounted[64];     /* directory where last mounted */
 841 /*C8*/  __le32  s_algorithm_usage_bitmap; /* For compression */
 842         /*
 843          * Performance hints.  Directory preallocation should only
 844          * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
 845          */
 846         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
 847         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
 848         __le16  s_reserved_gdt_blocks;  /* Per group desc for online growth */
 849         /*
 850          * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
 851          */
 852 /*D0*/  __u8    s_journal_uuid[16];     /* uuid of journal superblock */
 853 /*E0*/  __le32  s_journal_inum;         /* inode number of journal file */
 854         __le32  s_journal_dev;          /* device number of journal file */
 855         __le32  s_last_orphan;          /* start of list of inodes to delete */
 856         __le32  s_hash_seed[4];         /* HTREE hash seed */
 857         __u8    s_def_hash_version;     /* Default hash version to use */
 858         __u8    s_reserved_char_pad;
 859         __le16  s_desc_size;            /* size of group descriptor */
 860 /*100*/ __le32  s_default_mount_opts;
 861         __le32  s_first_meta_bg;        /* First metablock block group */
 862         __le32  s_mkfs_time;            /* When the filesystem was created */
 863         __le32  s_jnl_blocks[17];       /* Backup of the journal inode */
 864         /* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
 865 /*150*/ __le32  s_blocks_count_hi;      /* Blocks count */
 866         __le32  s_r_blocks_count_hi;    /* Reserved blocks count */
 867         __le32  s_free_blocks_count_hi; /* Free blocks count */
 868         __le16  s_min_extra_isize;      /* All inodes have at least # bytes */
 869         __le16  s_want_extra_isize;     /* New inodes should reserve # bytes */
 870         __le32  s_flags;                /* Miscellaneous flags */
 871         __le16  s_raid_stride;          /* RAID stride */
 872         __le16  s_mmp_interval;         /* # seconds to wait in MMP checking */
 873         __le64  s_mmp_block;            /* Block for multi-mount protection */
 874         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
 875         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
 876         __u8    s_reserved_char_pad2;
 877         __le16  s_reserved_pad;
 878         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
 879         __u32   s_reserved[160];        /* Padding to the end of the block */
 880 };
 881
 882 #ifdef __KERNEL__
 883
 884 /*
 885  * run-time mount flags
 886  */
 887 #define EXT4_MF_MNTDIR_SAMPLED  0x0001
 888 #define EXT4_MF_FS_ABORTED      0x0002  /* Fatal error detected */
 889
 890 /*
 891  * fourth extended-fs super-block data in memory
 892  */
 893 struct ext4_sb_info {
 894         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
 895         unsigned long s_inodes_per_block;/* Number of inodes per block */
 896         unsigned long s_blocks_per_group;/* Number of blocks in a group */
 897         unsigned long s_inodes_per_group;/* Number of inodes in a group */
 898         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
 899         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
 900         unsigned long s_desc_per_block; /* Number of group descriptors per block */
 901         ext4_group_t s_groups_count;    /* Number of groups in the fs */
 902         ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
 903         unsigned long s_overhead_last;  /* Last calculated overhead */
 904         unsigned long s_blocks_last;    /* Last seen block count */
 905         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
 906         struct buffer_head * s_sbh;     /* Buffer containing the super block */
 907         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
 908         struct buffer_head **s_group_desc;
 909         unsigned int s_mount_opt;
 910         unsigned int s_mount_flags;
 911         ext4_fsblk_t s_sb_block;
 912         uid_t s_resuid;
 913         gid_t s_resgid;
 914         unsigned short s_mount_state;
 915         unsigned short s_pad;
 916         int s_addr_per_block_bits;
 917         int s_desc_per_block_bits;
 918         int s_inode_size;
 919         int s_first_ino;
 920         unsigned int s_inode_readahead_blks;
 921         unsigned int s_inode_goal;
 922         spinlock_t s_next_gen_lock;
 923         u32 s_next_generation;
 924         u32 s_hash_seed[4];
 925         int s_def_hash_version;
 926         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
 927         struct percpu_counter s_freeblocks_counter;
 928         struct percpu_counter s_freeinodes_counter;
 929         struct percpu_counter s_dirs_counter;
 930         struct percpu_counter s_dirtyblocks_counter;
 931         struct blockgroup_lock *s_blockgroup_lock;
 932         struct proc_dir_entry *s_proc;
 933         struct kobject s_kobj;
 934         struct completion s_kobj_unregister;
 935
 936         /* Journaling */
 937         struct inode *s_journal_inode;
 938         struct journal_s *s_journal;
 939         struct list_head s_orphan;
 940         struct mutex s_orphan_lock;
 941         struct mutex s_resize_lock;
 942         unsigned long s_commit_interval;
 943         u32 s_max_batch_time;
 944         u32 s_min_batch_time;
 945         struct block_device *journal_bdev;
 946 #ifdef CONFIG_JBD2_DEBUG
 947         struct timer_list turn_ro_timer;        /* For turning read-only (crash simulation) */
 948         wait_queue_head_t ro_wait_queue;        /* For people waiting for the fs to go read-only */
 949 #endif
 950 #ifdef CONFIG_QUOTA
 951         char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
 952         int s_jquota_fmt;                       /* Format of quota to use */
 953 #endif
 954         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
 955         struct rb_root system_blks;
 956
 957 #ifdef EXTENTS_STATS
 958         /* ext4 extents stats */
 959         unsigned long s_ext_min;
 960         unsigned long s_ext_max;
 961         unsigned long s_depth_max;
 962         spinlock_t s_ext_stats_lock;
 963         unsigned long s_ext_blocks;
 964         unsigned long s_ext_extents;
 965 #endif
 966
 967         /* for buddy allocator */
 968         struct ext4_group_info ***s_group_info;
 969         struct inode *s_buddy_cache;
 970         long s_blocks_reserved;
 971         spinlock_t s_reserve_lock;
 972         spinlock_t s_md_lock;
 973         tid_t s_last_transaction;
 974         unsigned short *s_mb_offsets;
 975         unsigned int *s_mb_maxs;
 976
 977         /* tunables */
 978         unsigned long s_stripe;
 979         unsigned int s_mb_stream_request;
 980         unsigned int s_mb_max_to_scan;
 981         unsigned int s_mb_min_to_scan;
 982         unsigned int s_mb_stats;
 983         unsigned int s_mb_order2_reqs;
 984         unsigned int s_mb_group_prealloc;
 985         unsigned int s_max_writeback_mb_bump;
 986         /* where last allocation was done - for stream allocation */
 987         unsigned long s_mb_last_group;
 988         unsigned long s_mb_last_start;
 989
 990         /* stats for buddy allocator */
 991         spinlock_t s_mb_pa_lock;
 992         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
 993         atomic_t s_bal_success; /* we found long enough chunks */
 994         atomic_t s_bal_allocated;       /* in blocks */
 995         atomic_t s_bal_ex_scanned;      /* total extents scanned */
 996         atomic_t s_bal_goals;   /* goal hits */
 997         atomic_t s_bal_breaks;  /* too long searches */
 998         atomic_t s_bal_2orders; /* 2^order hits */
 999         spinlock_t s_bal_lock;
1000         unsigned long s_mb_buddies_generated;
1001         unsigned long long s_mb_generation_time;
1002         atomic_t s_mb_lost_chunks;
1003         atomic_t s_mb_preallocated;
1004         atomic_t s_mb_discarded;
1005         atomic_t s_lock_busy;
1006
1007         /* locality groups */
1008         struct ext4_locality_group *s_locality_groups;
1009
1010         /* for write statistics */
1011         unsigned long s_sectors_written_start;
1012         u64 s_kbytes_written;
1013
1014         unsigned int s_log_groups_per_flex;
1015         struct flex_groups *s_flex_groups;
1016
1017         /* workqueue for dio unwritten */
1018         struct workqueue_struct *dio_unwritten_wq;
1019 };
1020
1021 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
1022 {
1023         return sb->s_fs_info;
1024 }
1025 static inline struct ext4_inode_info *EXT4_I(struct inode *inode)
1026 {
1027         return container_of(inode, struct ext4_inode_info, vfs_inode);
1028 }
1029
1030 static inline struct timespec ext4_current_time(struct inode *inode)
1031 {
1032         return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
1033                 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
1034 }
1035
1036 static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
1037 {
1038         return ino == EXT4_ROOT_INO ||
1039                 ino == EXT4_JOURNAL_INO ||
1040                 ino == EXT4_RESIZE_INO ||
1041                 (ino >= EXT4_FIRST_INO(sb) &&
1042                  ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count));
1043 }
1044
1045 /*
1046  * Inode dynamic state flags
1047  */
1048 enum {
1049         EXT4_STATE_JDATA,               /* journaled data exists */
1050         EXT4_STATE_NEW,                 /* inode is newly created */
1051         EXT4_STATE_XATTR,               /* has in-inode xattrs */
1052         EXT4_STATE_NO_EXPAND,           /* No space for expansion */
1053         EXT4_STATE_DA_ALLOC_CLOSE,      /* Alloc DA blks on close */
1054         EXT4_STATE_EXT_MIGRATE,         /* Inode is migrating */
1055         EXT4_STATE_DIO_UNWRITTEN,       /* need convert on dio done*/
1056 };
1057
1058 static inline int ext4_test_inode_state(struct inode *inode, int bit)
1059 {
1060         return test_bit(bit, &EXT4_I(inode)->i_state_flags);
1061 }
1062
1063 static inline void ext4_set_inode_state(struct inode *inode, int bit)
1064 {
1065         set_bit(bit, &EXT4_I(inode)->i_state_flags);
1066 }
1067
1068 static inline void ext4_clear_inode_state(struct inode *inode, int bit)
1069 {
1070         clear_bit(bit, &EXT4_I(inode)->i_state_flags);
1071 }
1072 #else
1073 /* Assume that user mode programs are passing in an ext4fs superblock, not
1074  * a kernel struct super_block.  This will allow us to call the feature-test
1075  * macros from user land. */
1076 #define EXT4_SB(sb)     (sb)
1077 #endif
1078
1079 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
1080
1081 /*
1082  * Codes for operating systems
1083  */
1084 #define EXT4_OS_LINUX           0
1085 #define EXT4_OS_HURD            1
1086 #define EXT4_OS_MASIX           2
1087 #define EXT4_OS_FREEBSD         3
1088 #define EXT4_OS_LITES           4
1089
1090 /*
1091  * Revision levels
1092  */
1093 #define EXT4_GOOD_OLD_REV       0       /* The good old (original) format */
1094 #define EXT4_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
1095
1096 #define EXT4_CURRENT_REV        EXT4_GOOD_OLD_REV
1097 #define EXT4_MAX_SUPP_REV       EXT4_DYNAMIC_REV
1098
1099 #define EXT4_GOOD_OLD_INODE_SIZE 128
1100
1101 /*
1102  * Feature set definitions
1103  */
1104
1105 #define EXT4_HAS_COMPAT_FEATURE(sb,mask)                        \
1106         ((EXT4_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask)) != 0)
1107 #define EXT4_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
1108         ((EXT4_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask)) != 0)
1109 #define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)                      \
1110         ((EXT4_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask)) != 0)
1111 #define EXT4_SET_COMPAT_FEATURE(sb,mask)                        \
1112         EXT4_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
1113 #define EXT4_SET_RO_COMPAT_FEATURE(sb,mask)                     \
1114         EXT4_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
1115 #define EXT4_SET_INCOMPAT_FEATURE(sb,mask)                      \
1116         EXT4_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
1117 #define EXT4_CLEAR_COMPAT_FEATURE(sb,mask)                      \
1118         EXT4_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
1119 #define EXT4_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
1120         EXT4_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
1121 #define EXT4_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
1122         EXT4_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
1123
1124 #define EXT4_FEATURE_COMPAT_DIR_PREALLOC        0x0001
1125 #define EXT4_FEATURE_COMPAT_IMAGIC_INODES       0x0002
1126 #define EXT4_FEATURE_COMPAT_HAS_JOURNAL         0x0004
1127 #define EXT4_FEATURE_COMPAT_EXT_ATTR            0x0008
1128 #define EXT4_FEATURE_COMPAT_RESIZE_INODE        0x0010
1129 #define EXT4_FEATURE_COMPAT_DIR_INDEX           0x0020
1130
1131 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
1132 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
1133 #define EXT4_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
1134 #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE        0x0008
1135 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM         0x0010
1136 #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK        0x0020
1137 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
1138
1139 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
1140 #define EXT4_FEATURE_INCOMPAT_FILETYPE          0x0002
1141 #define EXT4_FEATURE_INCOMPAT_RECOVER           0x0004 /* Needs recovery */
1142 #define EXT4_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008 /* Journal device */
1143 #define EXT4_FEATURE_INCOMPAT_META_BG           0x0010
1144 #define EXT4_FEATURE_INCOMPAT_EXTENTS           0x0040 /* extents support */
1145 #define EXT4_FEATURE_INCOMPAT_64BIT             0x0080
1146 #define EXT4_FEATURE_INCOMPAT_MMP               0x0100
1147 #define EXT4_FEATURE_INCOMPAT_FLEX_BG           0x0200
1148 #define EXT4_FEATURE_INCOMPAT_EA_INODE          0x0400 /* EA in inode */
1149 #define EXT4_FEATURE_INCOMPAT_DIRDATA           0x1000 /* data in dirent */
1150
1151 #define EXT4_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
1152 #define EXT4_FEATURE_INCOMPAT_SUPP      (EXT4_FEATURE_INCOMPAT_FILETYPE| \
1153                                          EXT4_FEATURE_INCOMPAT_RECOVER| \
1154                                          EXT4_FEATURE_INCOMPAT_META_BG| \
1155                                          EXT4_FEATURE_INCOMPAT_EXTENTS| \
1156                                          EXT4_FEATURE_INCOMPAT_64BIT| \
1157                                          EXT4_FEATURE_INCOMPAT_FLEX_BG)
1158 #define EXT4_FEATURE_RO_COMPAT_SUPP     (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
1159                                          EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \
1160                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
1161                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK | \
1162                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
1163                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
1164                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE)
1165
1166 /*
1167  * Default values for user and/or group using reserved blocks
1168  */
1169 #define EXT4_DEF_RESUID         0
1170 #define EXT4_DEF_RESGID         0
1171
1172 #define EXT4_DEF_INODE_READAHEAD_BLKS   32
1173
1174 /*
1175  * Default mount options
1176  */
1177 #define EXT4_DEFM_DEBUG         0x0001
1178 #define EXT4_DEFM_BSDGROUPS     0x0002
1179 #define EXT4_DEFM_XATTR_USER    0x0004
1180 #define EXT4_DEFM_ACL           0x0008
1181 #define EXT4_DEFM_UID16         0x0010
1182 #define EXT4_DEFM_JMODE         0x0060
1183 #define EXT4_DEFM_JMODE_DATA    0x0020
1184 #define EXT4_DEFM_JMODE_ORDERED 0x0040
1185 #define EXT4_DEFM_JMODE_WBACK   0x0060
1186
1187 /*
1188  * Default journal batch times
1189  */
1190 #define EXT4_DEF_MIN_BATCH_TIME 0
1191 #define EXT4_DEF_MAX_BATCH_TIME 15000 /* 15ms */
1192
1193 /*
1194  * Minimum number of groups in a flexgroup before we separate out
1195  * directories into the first block group of a flexgroup
1196  */
1197 #define EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME 4
1198
1199 /*
1200  * Structure of a directory entry
1201  */
1202 #define EXT4_NAME_LEN 255
1203
1204 struct ext4_dir_entry {
1205         __le32  inode;                  /* Inode number */
1206         __le16  rec_len;                /* Directory entry length */
1207         __le16  name_len;               /* Name length */
1208         char    name[EXT4_NAME_LEN];    /* File name */
1209 };
1210
1211 /*
1212  * The new version of the directory entry.  Since EXT4 structures are
1213  * stored in intel byte order, and the name_len field could never be
1214  * bigger than 255 chars, it's safe to reclaim the extra byte for the
1215  * file_type field.
1216  */
1217 struct ext4_dir_entry_2 {
1218         __le32  inode;                  /* Inode number */
1219         __le16  rec_len;                /* Directory entry length */
1220         __u8    name_len;               /* Name length */
1221         __u8    file_type;
1222         char    name[EXT4_NAME_LEN];    /* File name */
1223 };
1224
1225 /*
1226  * Ext4 directory file types.  Only the low 3 bits are used.  The
1227  * other bits are reserved for now.
1228  */
1229 #define EXT4_FT_UNKNOWN         0
1230 #define EXT4_FT_REG_FILE        1
1231 #define EXT4_FT_DIR             2
1232 #define EXT4_FT_CHRDEV          3
1233 #define EXT4_FT_BLKDEV          4
1234 #define EXT4_FT_FIFO            5
1235 #define EXT4_FT_SOCK            6
1236 #define EXT4_FT_SYMLINK         7
1237
1238 #define EXT4_FT_MAX             8
1239
1240 /*
1241  * EXT4_DIR_PAD defines the directory entries boundaries
1242  *
1243  * NOTE: It must be a multiple of 4
1244  */
1245 #define EXT4_DIR_PAD                    4
1246 #define EXT4_DIR_ROUND                  (EXT4_DIR_PAD - 1)
1247 #define EXT4_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT4_DIR_ROUND) & \
1248                                          ~EXT4_DIR_ROUND)
1249 #define EXT4_MAX_REC_LEN                ((1<<16)-1)
1250
1251 /*
1252  * Hash Tree Directory indexing
1253  * (c) Daniel Phillips, 2001
1254  */
1255
1256 #define is_dx(dir) (EXT4_HAS_COMPAT_FEATURE(dir->i_sb, \
1257                                       EXT4_FEATURE_COMPAT_DIR_INDEX) && \
1258                       (EXT4_I(dir)->i_flags & EXT4_INDEX_FL))
1259 #define EXT4_DIR_LINK_MAX(dir) (!is_dx(dir) && (dir)->i_nlink >= EXT4_LINK_MAX)
1260 #define EXT4_DIR_LINK_EMPTY(dir) ((dir)->i_nlink == 2 || (dir)->i_nlink == 1)
1261
1262 /* Legal values for the dx_root hash_version field: */
1263
1264 #define DX_HASH_LEGACY          0
1265 #define DX_HASH_HALF_MD4        1
1266 #define DX_HASH_TEA             2
1267 #define DX_HASH_LEGACY_UNSIGNED 3
1268 #define DX_HASH_HALF_MD4_UNSIGNED       4
1269 #define DX_HASH_TEA_UNSIGNED            5
1270
1271 #ifdef __KERNEL__
1272
1273 /* hash info structure used by the directory hash */
1274 struct dx_hash_info
1275 {
1276         u32             hash;
1277         u32             minor_hash;
1278         int             hash_version;
1279         u32             *seed;
1280 };
1281
1282 #define EXT4_HTREE_EOF  0x7fffffff
1283
1284 /*
1285  * Control parameters used by ext4_htree_next_block
1286  */
1287 #define HASH_NB_ALWAYS          1
1288
1289
1290 /*
1291  * Describe an inode's exact location on disk and in memory
1292  */
1293 struct ext4_iloc
1294 {
1295         struct buffer_head *bh;
1296         unsigned long offset;
1297         ext4_group_t block_group;
1298 };
1299
1300 static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc)
1301 {
1302         return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset);
1303 }
1304
1305 /*
1306  * This structure is stuffed into the struct file's private_data field
1307  * for directories.  It is where we put information so that we can do
1308  * readdir operations in hash tree order.
1309  */
1310 struct dir_private_info {
1311         struct rb_root  root;
1312         struct rb_node  *curr_node;
1313         struct fname    *extra_fname;
1314         loff_t          last_pos;
1315         __u32           curr_hash;
1316         __u32           curr_minor_hash;
1317         __u32           next_hash;
1318 };
1319
1320 /* calculate the first block number of the group */
1321 static inline ext4_fsblk_t
1322 ext4_group_first_block_no(struct super_block *sb, ext4_group_t group_no)
1323 {
1324         return group_no * (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
1325                 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
1326 }
1327
1328 /*
1329  * Special error return code only used by dx_probe() and its callers.
1330  */
1331 #define ERR_BAD_DX_DIR  -75000
1332
1333 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
1334                         ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp);
1335
1336 extern struct proc_dir_entry *ext4_proc_root;
1337
1338 /*
1339  * Function prototypes
1340  */
1341
1342 /*
1343  * Ok, these declarations are also in <linux/kernel.h> but none of the
1344  * ext4 source programs needs to include it so they are duplicated here.
1345  */
1346 # define NORET_TYPE     /**/
1347 # define ATTRIB_NORET   __attribute__((noreturn))
1348 # define NORET_AND      noreturn,
1349
1350 /* bitmap.c */
1351 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
1352
1353 /* balloc.c */
1354 extern unsigned int ext4_block_group(struct super_block *sb,
1355                         ext4_fsblk_t blocknr);
1356 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
1357                         ext4_fsblk_t blocknr);
1358 extern int ext4_bg_has_super(struct super_block *sb, ext4_group_t group);
1359 extern unsigned long ext4_bg_num_gdb(struct super_block *sb,
1360                         ext4_group_t group);
1361 extern ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
1362                         ext4_fsblk_t goal, unsigned long *count, int *errp);
1363 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1364 extern int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
1365 extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
1366                                 ext4_fsblk_t block, unsigned long count);
1367 extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);
1368 extern void ext4_check_blocks_bitmap(struct super_block *);
1369 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
1370                                                     ext4_group_t block_group,
1371                                                     struct buffer_head ** bh);
1372 extern int ext4_should_retry_alloc(struct super_block *sb, int *retries);
1373 struct buffer_head *ext4_read_block_bitmap(struct super_block *sb,
1374                                       ext4_group_t block_group);
1375 extern unsigned ext4_init_block_bitmap(struct super_block *sb,
1376                                        struct buffer_head *bh,
1377                                        ext4_group_t group,
1378                                        struct ext4_group_desc *desc);
1379 #define ext4_free_blocks_after_init(sb, group, desc)                    \
1380                 ext4_init_block_bitmap(sb, NULL, group, desc)
1381
1382 /* dir.c */
1383 extern int ext4_check_dir_entry(const char *, struct inode *,
1384                                 struct ext4_dir_entry_2 *,
1385                                 struct buffer_head *, unsigned int);
1386 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
1387                                     __u32 minor_hash,
1388                                     struct ext4_dir_entry_2 *dirent);
1389 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
1390
1391 /* fsync.c */
1392 extern int ext4_sync_file(struct file *, struct dentry *, int);
1393
1394 /* hash.c */
1395 extern int ext4fs_dirhash(const char *name, int len, struct
1396                           dx_hash_info *hinfo);
1397
1398 /* ialloc.c */
1399 extern struct inode *ext4_new_inode(handle_t *, struct inode *, int,
1400                                     const struct qstr *qstr, __u32 goal);
1401 extern void ext4_free_inode(handle_t *, struct inode *);
1402 extern struct inode * ext4_orphan_get(struct super_block *, unsigned long);
1403 extern unsigned long ext4_count_free_inodes(struct super_block *);
1404 extern unsigned long ext4_count_dirs(struct super_block *);
1405 extern void ext4_check_inodes_bitmap(struct super_block *);
1406 extern unsigned ext4_init_inode_bitmap(struct super_block *sb,
1407                                        struct buffer_head *bh,
1408                                        ext4_group_t group,
1409                                        struct ext4_group_desc *desc);
1410 extern void mark_bitmap_end(int start_bit, int end_bit, char *bitmap);
1411
1412 /* mballoc.c */
1413 extern long ext4_mb_stats;
1414 extern long ext4_mb_max_to_scan;
1415 extern int ext4_mb_init(struct super_block *, int);
1416 extern int ext4_mb_release(struct super_block *);
1417 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
1418                                 struct ext4_allocation_request *, int *);
1419 extern int ext4_mb_reserve_blocks(struct super_block *, int);
1420 extern void ext4_discard_preallocations(struct inode *);
1421 extern int __init init_ext4_mballoc(void);
1422 extern void exit_ext4_mballoc(void);
1423 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
1424                              struct buffer_head *bh, ext4_fsblk_t block,
1425                              unsigned long count, int flags);
1426 extern int ext4_mb_add_groupinfo(struct super_block *sb,
1427                 ext4_group_t i, struct ext4_group_desc *desc);
1428 extern int ext4_mb_get_buddy_cache_lock(struct super_block *, ext4_group_t);
1429 extern void ext4_mb_put_buddy_cache_lock(struct super_block *,
1430                                                 ext4_group_t, int);
1431 /* inode.c */
1432 struct buffer_head *ext4_getblk(handle_t *, struct inode *,
1433                                                 ext4_lblk_t, int, int *);
1434 struct buffer_head *ext4_bread(handle_t *, struct inode *,
1435                                                 ext4_lblk_t, int, int *);
1436 int ext4_get_block(struct inode *inode, sector_t iblock,
1437                                 struct buffer_head *bh_result, int create);
1438
1439 extern struct inode *ext4_iget(struct super_block *, unsigned long);
1440 extern int  ext4_write_inode(struct inode *, int);
1441 extern int  ext4_setattr(struct dentry *, struct iattr *);
1442 extern int  ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
1443                                 struct kstat *stat);
1444 extern void ext4_delete_inode(struct inode *);
1445 extern int  ext4_sync_inode(handle_t *, struct inode *);
1446 extern void ext4_dirty_inode(struct inode *);
1447 extern int ext4_change_inode_journal_flag(struct inode *, int);
1448 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
1449 extern int ext4_can_truncate(struct inode *inode);
1450 extern void ext4_truncate(struct inode *);
1451 extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks);
1452 extern void ext4_set_inode_flags(struct inode *);
1453 extern void ext4_get_inode_flags(struct ext4_inode_info *);
1454 extern int ext4_alloc_da_blocks(struct inode *inode);
1455 extern void ext4_set_aops(struct inode *inode);
1456 extern int ext4_writepage_trans_blocks(struct inode *);
1457 extern int ext4_meta_trans_blocks(struct inode *, int nrblocks, int idxblocks);
1458 extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks);
1459 extern int ext4_block_truncate_page(handle_t *handle,
1460                 struct address_space *mapping, loff_t from);
1461 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
1462 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
1463 extern int flush_aio_dio_completed_IO(struct inode *inode);
1464 extern void ext4_da_update_reserve_space(struct inode *inode,
1465                                         int used, int quota_claim);
1466 /* ioctl.c */
1467 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
1468 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
1469
1470 /* migrate.c */
1471 extern int ext4_ext_migrate(struct inode *);
1472
1473 /* namei.c */
1474 extern unsigned int ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize);
1475 extern __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize);
1476 extern int ext4_orphan_add(handle_t *, struct inode *);
1477 extern int ext4_orphan_del(handle_t *, struct inode *);
1478 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1479                                 __u32 start_minor_hash, __u32 *next_hash);
1480
1481 /* resize.c */
1482 extern int ext4_group_add(struct super_block *sb,
1483                                 struct ext4_new_group_data *input);
1484 extern int ext4_group_extend(struct super_block *sb,
1485                                 struct ext4_super_block *es,
1486                                 ext4_fsblk_t n_blocks_count);
1487
1488 /* super.c */
1489 extern void __ext4_error(struct super_block *, const char *, const char *, ...)
1490         __attribute__ ((format (printf, 3, 4)));
1491 #define ext4_error(sb, message...)      __ext4_error(sb, __func__, ## message)
1492 extern void __ext4_std_error(struct super_block *, const char *, int);
1493 extern void ext4_abort(struct super_block *, const char *, const char *, ...)
1494         __attribute__ ((format (printf, 3, 4)));
1495 extern void __ext4_warning(struct super_block *, const char *,
1496                           const char *, ...)
1497         __attribute__ ((format (printf, 3, 4)));
1498 #define ext4_warning(sb, message...)    __ext4_warning(sb, __func__, ## message)
1499 extern void ext4_msg(struct super_block *, const char *, const char *, ...)
1500         __attribute__ ((format (printf, 3, 4)));
1501 extern void ext4_grp_locked_error(struct super_block *, ext4_group_t,
1502                                 const char *, const char *, ...)
1503         __attribute__ ((format (printf, 4, 5)));
1504 extern void ext4_update_dynamic_rev(struct super_block *sb);
1505 extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
1506                                         __u32 compat);
1507 extern int ext4_update_rocompat_feature(handle_t *handle,
1508                                         struct super_block *sb, __u32 rocompat);
1509 extern int ext4_update_incompat_feature(handle_t *handle,
1510                                         struct super_block *sb, __u32 incompat);
1511 extern ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
1512                                       struct ext4_group_desc *bg);
1513 extern ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
1514                                       struct ext4_group_desc *bg);
1515 extern ext4_fsblk_t ext4_inode_table(struct super_block *sb,
1516                                      struct ext4_group_desc *bg);
1517 extern __u32 ext4_free_blks_count(struct super_block *sb,
1518                                 struct ext4_group_desc *bg);
1519 extern __u32 ext4_free_inodes_count(struct super_block *sb,
1520                                  struct ext4_group_desc *bg);
1521 extern __u32 ext4_used_dirs_count(struct super_block *sb,
1522                                 struct ext4_group_desc *bg);
1523 extern __u32 ext4_itable_unused_count(struct super_block *sb,
1524                                    struct ext4_group_desc *bg);
1525 extern void ext4_block_bitmap_set(struct super_block *sb,
1526                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1527 extern void ext4_inode_bitmap_set(struct super_block *sb,
1528                                   struct ext4_group_desc *bg, ext4_fsblk_t blk);
1529 extern void ext4_inode_table_set(struct super_block *sb,
1530                                  struct ext4_group_desc *bg, ext4_fsblk_t blk);
1531 extern void ext4_free_blks_set(struct super_block *sb,
1532                                struct ext4_group_desc *bg, __u32 count);
1533 extern void ext4_free_inodes_set(struct super_block *sb,
1534                                 struct ext4_group_desc *bg, __u32 count);
1535 extern void ext4_used_dirs_set(struct super_block *sb,
1536                                 struct ext4_group_desc *bg, __u32 count);
1537 extern void ext4_itable_unused_set(struct super_block *sb,
1538                                    struct ext4_group_desc *bg, __u32 count);
1539 extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
1540                                    struct ext4_group_desc *gdp);
1541 extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
1542                                        struct ext4_group_desc *gdp);
1543
1544 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
1545 {
1546         return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) |
1547                 le32_to_cpu(es->s_blocks_count_lo);
1548 }
1549
1550 static inline ext4_fsblk_t ext4_r_blocks_count(struct ext4_super_block *es)
1551 {
1552         return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) |
1553                 le32_to_cpu(es->s_r_blocks_count_lo);
1554 }
1555
1556 static inline ext4_fsblk_t ext4_free_blocks_count(struct ext4_super_block *es)
1557 {
1558         return ((ext4_fsblk_t)le32_to_cpu(es->s_free_blocks_count_hi) << 32) |
1559                 le32_to_cpu(es->s_free_blocks_count_lo);
1560 }
1561
1562 static inline void ext4_blocks_count_set(struct ext4_super_block *es,
1563                                          ext4_fsblk_t blk)
1564 {
1565         es->s_blocks_count_lo = cpu_to_le32((u32)blk);
1566         es->s_blocks_count_hi = cpu_to_le32(blk >> 32);
1567 }
1568
1569 static inline void ext4_free_blocks_count_set(struct ext4_super_block *es,
1570                                               ext4_fsblk_t blk)
1571 {
1572         es->s_free_blocks_count_lo = cpu_to_le32((u32)blk);
1573         es->s_free_blocks_count_hi = cpu_to_le32(blk >> 32);
1574 }
1575
1576 static inline void ext4_r_blocks_count_set(struct ext4_super_block *es,
1577                                            ext4_fsblk_t blk)
1578 {
1579         es->s_r_blocks_count_lo = cpu_to_le32((u32)blk);
1580         es->s_r_blocks_count_hi = cpu_to_le32(blk >> 32);
1581 }
1582
1583 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
1584 {
1585         if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
1586                 return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
1587                         le32_to_cpu(raw_inode->i_size_lo);
1588         else
1589                 return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
1590 }
1591
1592 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
1593 {
1594         raw_inode->i_size_lo = cpu_to_le32(i_size);
1595         raw_inode->i_size_high = cpu_to_le32(i_size >> 32);
1596 }
1597
1598 static inline
1599 struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
1600                                             ext4_group_t group)
1601 {
1602          struct ext4_group_info ***grp_info;
1603          long indexv, indexh;
1604          grp_info = EXT4_SB(sb)->s_group_info;
1605          indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
1606          indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);
1607          return grp_info[indexv][indexh];
1608 }
1609
1610 /*
1611  * Reading s_groups_count requires using smp_rmb() afterwards.  See
1612  * the locking protocol documented in the comments of ext4_group_add()
1613  * in resize.c
1614  */
1615 static inline ext4_group_t ext4_get_groups_count(struct super_block *sb)
1616 {
1617         ext4_group_t    ngroups = EXT4_SB(sb)->s_groups_count;
1618
1619         smp_rmb();
1620         return ngroups;
1621 }
1622
1623 static inline ext4_group_t ext4_flex_group(struct ext4_sb_info *sbi,
1624                                              ext4_group_t block_group)
1625 {
1626         return block_group >> sbi->s_log_groups_per_flex;
1627 }
1628
1629 static inline unsigned int ext4_flex_bg_size(struct ext4_sb_info *sbi)
1630 {
1631         return 1 << sbi->s_log_groups_per_flex;
1632 }
1633
1634 #define ext4_std_error(sb, errno)                               \
1635 do {                                                            \
1636         if ((errno))                                            \
1637                 __ext4_std_error((sb), __func__, (errno));      \
1638 } while (0)
1639
1640 #ifdef CONFIG_SMP
1641 /* Each CPU can accumulate percpu_counter_batch blocks in their local
1642  * counters. So we need to make sure we have free blocks more
1643  * than percpu_counter_batch  * nr_cpu_ids. Also add a window of 4 times.
1644  */
1645 #define EXT4_FREEBLOCKS_WATERMARK (4 * (percpu_counter_batch * nr_cpu_ids))
1646 #else
1647 #define EXT4_FREEBLOCKS_WATERMARK 0
1648 #endif
1649
1650 static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
1651 {
1652         /*
1653          * XXX: replace with spinlock if seen contended -bzzz
1654          */
1655         down_write(&EXT4_I(inode)->i_data_sem);
1656         if (newsize > EXT4_I(inode)->i_disksize)
1657                 EXT4_I(inode)->i_disksize = newsize;
1658         up_write(&EXT4_I(inode)->i_data_sem);
1659         return ;
1660 }
1661
1662 struct ext4_group_info {
1663         unsigned long   bb_state;
1664         struct rb_root  bb_free_root;
1665         ext4_grpblk_t   bb_first_free;  /* first free block */
1666         ext4_grpblk_t   bb_free;        /* total free blocks */
1667         ext4_grpblk_t   bb_fragments;   /* nr of freespace fragments */
1668         struct          list_head bb_prealloc_list;
1669 #ifdef DOUBLE_CHECK
1670         void            *bb_bitmap;
1671 #endif
1672         struct rw_semaphore alloc_sem;
1673         ext4_grpblk_t   bb_counters[];  /* Nr of free power-of-two-block
1674                                          * regions, index is order.
1675                                          * bb_counters[3] = 5 means
1676                                          * 5 free 8-block regions. */
1677 };
1678
1679 #define EXT4_GROUP_INFO_NEED_INIT_BIT   0
1680
1681 #define EXT4_MB_GRP_NEED_INIT(grp)      \
1682         (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state)))
1683
1684 #define EXT4_MAX_CONTENTION             8
1685 #define EXT4_CONTENTION_THRESHOLD       2
1686
1687 static inline spinlock_t *ext4_group_lock_ptr(struct super_block *sb,
1688                                               ext4_group_t group)
1689 {
1690         return bgl_lock_ptr(EXT4_SB(sb)->s_blockgroup_lock, group);
1691 }
1692
1693 /*
1694  * Returns true if the filesystem is busy enough that attempts to
1695  * access the block group locks has run into contention.
1696  */
1697 static inline int ext4_fs_is_busy(struct ext4_sb_info *sbi)
1698 {
1699         return (atomic_read(&sbi->s_lock_busy) > EXT4_CONTENTION_THRESHOLD);
1700 }
1701
1702 static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group)
1703 {
1704         spinlock_t *lock = ext4_group_lock_ptr(sb, group);
1705         if (spin_trylock(lock))
1706                 /*
1707                  * We're able to grab the lock right away, so drop the
1708                  * lock contention counter.
1709                  */
1710                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, -1, 0);
1711         else {
1712                 /*
1713                  * The lock is busy, so bump the contention counter,
1714                  * and then wait on the spin lock.
1715                  */
1716                 atomic_add_unless(&EXT4_SB(sb)->s_lock_busy, 1,
1717                                   EXT4_MAX_CONTENTION);
1718                 spin_lock(lock);
1719         }
1720 }
1721
1722 static inline void ext4_unlock_group(struct super_block *sb,
1723                                         ext4_group_t group)
1724 {
1725         spin_unlock(ext4_group_lock_ptr(sb, group));
1726 }
1727
1728 /*
1729  * Inodes and files operations
1730  */
1731
1732 /* dir.c */
1733 extern const struct file_operations ext4_dir_operations;
1734
1735 /* file.c */
1736 extern const struct inode_operations ext4_file_inode_operations;
1737 extern const struct file_operations ext4_file_operations;
1738
1739 /* namei.c */
1740 extern const struct inode_operations ext4_dir_inode_operations;
1741 extern const struct inode_operations ext4_special_inode_operations;
1742 extern struct dentry *ext4_get_parent(struct dentry *child);
1743
1744 /* symlink.c */
1745 extern const struct inode_operations ext4_symlink_inode_operations;
1746 extern const struct inode_operations ext4_fast_symlink_inode_operations;
1747
1748 /* block_validity */
1749 extern void ext4_release_system_zone(struct super_block *sb);
1750 extern int ext4_setup_system_zone(struct super_block *sb);
1751 extern int __init init_ext4_system_zone(void);
1752 extern void exit_ext4_system_zone(void);
1753 extern int ext4_data_block_valid(struct ext4_sb_info *sbi,
1754                                  ext4_fsblk_t start_blk,
1755                                  unsigned int count);
1756
1757 /* extents.c */
1758 extern int ext4_ext_tree_init(handle_t *handle, struct inode *);
1759 extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
1760 extern int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks,
1761                                        int chunk);
1762 extern int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
1763                                ext4_lblk_t iblock, unsigned int max_blocks,
1764                                struct buffer_head *bh_result, int flags);
1765 extern void ext4_ext_truncate(struct inode *);
1766 extern void ext4_ext_init(struct super_block *);
1767 extern void ext4_ext_release(struct super_block *);
1768 extern long ext4_fallocate(struct inode *inode, int mode, loff_t offset,
1769                           loff_t len);
1770 extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
1771                           ssize_t len);
1772 extern int ext4_get_blocks(handle_t *handle, struct inode *inode,
1773                            sector_t block, unsigned int max_blocks,
1774                            struct buffer_head *bh, int flags);
1775 extern int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1776                         __u64 start, __u64 len);
1777 /* move_extent.c */
1778 extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
1779                              __u64 start_orig, __u64 start_donor,
1780                              __u64 len, __u64 *moved_len);
1781
1782
1783 /*
1784  * Add new method to test wether block and inode bitmaps are properly
1785  * initialized. With uninit_bg reading the block from disk is not enough
1786  * to mark the bitmap uptodate. We need to also zero-out the bitmap
1787  */
1788 #define BH_BITMAP_UPTODATE BH_JBDPrivateStart
1789
1790 static inline int bitmap_uptodate(struct buffer_head *bh)
1791 {
1792         return (buffer_uptodate(bh) &&
1793                         test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
1794 }
1795 static inline void set_bitmap_uptodate(struct buffer_head *bh)
1796 {
1797         set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
1798 }
1799
1800 #endif  /* __KERNEL__ */
1801
1802 #endif  /* _EXT4_H */