LXR linux/include/uapi/linux/nilfs2

   1/* SPDX-License-Identifier: LGPL-2.1+ WITH Linux-syscall-note */
   2/*
   3 * nilfs2_ondisk.h - NILFS2 on-disk structures
   4 *
   5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU Lesser General Public License as published
   9 * by the Free Software Foundation; either version 2.1 of the License, or
  10 * (at your option) any later version.
  11 */
  12/*
  13 *  linux/include/linux/ext2_fs.h
  14 *
  15 * Copyright (C) 1992, 1993, 1994, 1995
  16 * Remy Card (card@masi.ibp.fr)
  17 * Laboratoire MASI - Institut Blaise Pascal
  18 * Universite Pierre et Marie Curie (Paris VI)
  19 *
  20 *  from
  21 *
  22 *  linux/include/linux/minix_fs.h
  23 *
  24 *  Copyright (C) 1991, 1992  Linus Torvalds
  25 */
  26
  27#ifndef _LINUX_NILFS2_ONDISK_H
  28#define _LINUX_NILFS2_ONDISK_H
  29
  30#include <linux/types.h>
  31#include <linux/magic.h>
  32
  33
  34#define NILFS_INODE_BMAP_SIZE   7
  35
  36/**
  37 * struct nilfs_inode - structure of an inode on disk
  38 * @i_blocks: blocks count
  39 * @i_size: size in bytes
  40 * @i_ctime: creation time (seconds)
  41 * @i_mtime: modification time (seconds)
  42 * @i_ctime_nsec: creation time (nano seconds)
  43 * @i_mtime_nsec: modification time (nano seconds)
  44 * @i_uid: user id
  45 * @i_gid: group id
  46 * @i_mode: file mode
  47 * @i_links_count: links count
  48 * @i_flags: file flags
  49 * @i_bmap: block mapping
  50 * @i_xattr: extended attributes
  51 * @i_generation: file generation (for NFS)
  52 * @i_pad: padding
  53 */
  54struct nilfs_inode {
  55        __le64  i_blocks;
  56        __le64  i_size;
  57        __le64  i_ctime;
  58        __le64  i_mtime;
  59        __le32  i_ctime_nsec;
  60        __le32  i_mtime_nsec;
  61        __le32  i_uid;
  62        __le32  i_gid;
  63        __le16  i_mode;
  64        __le16  i_links_count;
  65        __le32  i_flags;
  66        __le64  i_bmap[NILFS_INODE_BMAP_SIZE];
  67#define i_device_code   i_bmap[0]
  68        __le64  i_xattr;
  69        __le32  i_generation;
  70        __le32  i_pad;
  71};
  72
  73#define NILFS_MIN_INODE_SIZE            128
  74
  75/**
  76 * struct nilfs_super_root - structure of super root
  77 * @sr_sum: check sum
  78 * @sr_bytes: byte count of the structure
  79 * @sr_flags: flags (reserved)
  80 * @sr_nongc_ctime: write time of the last segment not for cleaner operation
  81 * @sr_dat: DAT file inode
  82 * @sr_cpfile: checkpoint file inode
  83 * @sr_sufile: segment usage file inode
  84 */
  85struct nilfs_super_root {
  86        __le32 sr_sum;
  87        __le16 sr_bytes;
  88        __le16 sr_flags;
  89        __le64 sr_nongc_ctime;
  90        struct nilfs_inode sr_dat;
  91        struct nilfs_inode sr_cpfile;
  92        struct nilfs_inode sr_sufile;
  93};
  94
  95#define NILFS_SR_MDT_OFFSET(inode_size, i)  \
  96        ((unsigned long)&((struct nilfs_super_root *)0)->sr_dat + \
  97                        (inode_size) * (i))
  98#define NILFS_SR_DAT_OFFSET(inode_size)     NILFS_SR_MDT_OFFSET(inode_size, 0)
  99#define NILFS_SR_CPFILE_OFFSET(inode_size)  NILFS_SR_MDT_OFFSET(inode_size, 1)
 100#define NILFS_SR_SUFILE_OFFSET(inode_size)  NILFS_SR_MDT_OFFSET(inode_size, 2)
 101#define NILFS_SR_BYTES(inode_size)          NILFS_SR_MDT_OFFSET(inode_size, 3)
 102
 103/*
 104 * Maximal mount counts
 105 */
 106#define NILFS_DFL_MAX_MNT_COUNT         50      /* 50 mounts */
 107
 108/*
 109 * File system states (sbp->s_state, nilfs->ns_mount_state)
 110 */
 111#define NILFS_VALID_FS                  0x0001  /* Unmounted cleanly */
 112#define NILFS_ERROR_FS                  0x0002  /* Errors detected */
 113#define NILFS_RESIZE_FS                 0x0004  /* Resize required */
 114
 115/*
 116 * Mount flags (sbi->s_mount_opt)
 117 */
 118#define NILFS_MOUNT_ERROR_MODE          0x0070  /* Error mode mask */
 119#define NILFS_MOUNT_ERRORS_CONT         0x0010  /* Continue on errors */
 120#define NILFS_MOUNT_ERRORS_RO           0x0020  /* Remount fs ro on errors */
 121#define NILFS_MOUNT_ERRORS_PANIC        0x0040  /* Panic on errors */
 122#define NILFS_MOUNT_BARRIER             0x1000  /* Use block barriers */
 123#define NILFS_MOUNT_STRICT_ORDER        0x2000  /*
 124                                                 * Apply strict in-order
 125                                                 * semantics also for data
 126                                                 */
 127#define NILFS_MOUNT_NORECOVERY          0x4000  /*
 128                                                 * Disable write access during
 129                                                 * mount-time recovery
 130                                                 */
 131#define NILFS_MOUNT_DISCARD             0x8000  /* Issue DISCARD requests */
 132
 133
 134/**
 135 * struct nilfs_super_block - structure of super block on disk
 136 */
 137struct nilfs_super_block {
 138/*00*/  __le32  s_rev_level;            /* Revision level */
 139        __le16  s_minor_rev_level;      /* minor revision level */
 140        __le16  s_magic;                /* Magic signature */
 141
 142        __le16  s_bytes;                /*
 143                                         * Bytes count of CRC calculation
 144                                         * for this structure. s_reserved
 145                                         * is excluded.
 146                                         */
 147        __le16  s_flags;                /* flags */
 148        __le32  s_crc_seed;             /* Seed value of CRC calculation */
 149/*10*/  __le32  s_sum;                  /* Check sum of super block */
 150
 151        __le32  s_log_block_size;       /*
 152                                         * Block size represented as follows
 153                                         * blocksize =
 154                                         *     1 << (s_log_block_size + 10)
 155                                         */
 156        __le64  s_nsegments;            /* Number of segments in filesystem */
 157/*20*/  __le64  s_dev_size;             /* block device size in bytes */
 158        __le64  s_first_data_block;     /* 1st seg disk block number */
 159/*30*/  __le32  s_blocks_per_segment;   /* number of blocks per full segment */
 160        __le32  s_r_segments_percentage; /* Reserved segments percentage */
 161
 162        __le64  s_last_cno;             /* Last checkpoint number */
 163/*40*/  __le64  s_last_pseg;            /* disk block addr pseg written last */
 164        __le64  s_last_seq;             /* seq. number of seg written last */
 165/*50*/  __le64  s_free_blocks_count;    /* Free blocks count */
 166
 167        __le64  s_ctime;                /*
 168                                         * Creation time (execution time of
 169                                         * newfs)
 170                                         */
 171/*60*/  __le64  s_mtime;                /* Mount time */
 172        __le64  s_wtime;                /* Write time */
 173/*70*/  __le16  s_mnt_count;            /* Mount count */
 174        __le16  s_max_mnt_count;        /* Maximal mount count */
 175        __le16  s_state;                /* File system state */
 176        __le16  s_errors;               /* Behaviour when detecting errors */
 177        __le64  s_lastcheck;            /* time of last check */
 178
 179/*80*/  __le32  s_checkinterval;        /* max. time between checks */
 180        __le32  s_creator_os;           /* OS */
 181        __le16  s_def_resuid;           /* Default uid for reserved blocks */
 182        __le16  s_def_resgid;           /* Default gid for reserved blocks */
 183        __le32  s_first_ino;            /* First non-reserved inode */
 184
 185/*90*/  __le16  s_inode_size;           /* Size of an inode */
 186        __le16  s_dat_entry_size;       /* Size of a dat entry */
 187        __le16  s_checkpoint_size;      /* Size of a checkpoint */
 188        __le16  s_segment_usage_size;   /* Size of a segment usage */
 189
 190/*98*/  __u8    s_uuid[16];             /* 128-bit uuid for volume */
 191/*A8*/  char    s_volume_name[80];      /* volume name */
 192
 193/*F8*/  __le32  s_c_interval;           /* Commit interval of segment */
 194        __le32  s_c_block_max;          /*
 195                                         * Threshold of data amount for
 196                                         * the segment construction
 197                                         */
 198/*100*/ __le64  s_feature_compat;       /* Compatible feature set */
 199        __le64  s_feature_compat_ro;    /* Read-only compatible feature set */
 200        __le64  s_feature_incompat;     /* Incompatible feature set */
 201        __u32   s_reserved[186];        /* padding to the end of the block */
 202};
 203
 204/*
 205 * Codes for operating systems
 206 */
 207#define NILFS_OS_LINUX          0
 208/* Codes from 1 to 4 are reserved to keep compatibility with ext2 creator-OS */
 209
 210/*
 211 * Revision levels
 212 */
 213#define NILFS_CURRENT_REV       2       /* current major revision */
 214#define NILFS_MINOR_REV         0       /* minor revision */
 215#define NILFS_MIN_SUPP_REV      2       /* minimum supported revision */
 216
 217/*
 218 * Feature set definitions
 219 *
 220 * If there is a bit set in the incompatible feature set that the kernel
 221 * doesn't know about, it should refuse to mount the filesystem.
 222 */
 223#define NILFS_FEATURE_COMPAT_RO_BLOCK_COUNT     0x00000001ULL
 224
 225#define NILFS_FEATURE_COMPAT_SUPP       0ULL
 226#define NILFS_FEATURE_COMPAT_RO_SUPP    NILFS_FEATURE_COMPAT_RO_BLOCK_COUNT
 227#define NILFS_FEATURE_INCOMPAT_SUPP     0ULL
 228
 229/*
 230 * Bytes count of super_block for CRC-calculation
 231 */
 232#define NILFS_SB_BYTES  \
 233        ((long)&((struct nilfs_super_block *)0)->s_reserved)
 234
 235/*
 236 * Special inode number
 237 */
 238#define NILFS_ROOT_INO          2       /* Root file inode */
 239#define NILFS_DAT_INO           3       /* DAT file */
 240#define NILFS_CPFILE_INO        4       /* checkpoint file */
 241#define NILFS_SUFILE_INO        5       /* segment usage file */
 242#define NILFS_IFILE_INO         6       /* ifile */
 243#define NILFS_ATIME_INO         7       /* Atime file (reserved) */
 244#define NILFS_XATTR_INO         8       /* Xattribute file (reserved) */
 245#define NILFS_SKETCH_INO        10      /* Sketch file */
 246#define NILFS_USER_INO          11      /* Fisrt user's file inode number */
 247
 248#define NILFS_SB_OFFSET_BYTES   1024    /* byte offset of nilfs superblock */
 249
 250#define NILFS_SEG_MIN_BLOCKS    16      /*
 251                                         * Minimum number of blocks in
 252                                         * a full segment
 253                                         */
 254#define NILFS_PSEG_MIN_BLOCKS   2       /*
 255                                         * Minimum number of blocks in
 256                                         * a partial segment
 257                                         */
 258#define NILFS_MIN_NRSVSEGS      8       /*
 259                                         * Minimum number of reserved
 260                                         * segments
 261                                         */
 262
 263/*
 264 * We call DAT, cpfile, and sufile root metadata files.  Inodes of
 265 * these files are written in super root block instead of ifile, and
 266 * garbage collector doesn't keep any past versions of these files.
 267 */
 268#define NILFS_ROOT_METADATA_FILE(ino) \
 269        ((ino) >= NILFS_DAT_INO && (ino) <= NILFS_SUFILE_INO)
 270
 271/*
 272 * bytes offset of secondary super block
 273 */
 274#define NILFS_SB2_OFFSET_BYTES(devsize) ((((devsize) >> 12) - 1) << 12)
 275
 276/*
 277 * Maximal count of links to a file
 278 */
 279#define NILFS_LINK_MAX          32000
 280
 281/*
 282 * Structure of a directory entry
 283 *  (Same as ext2)
 284 */
 285
 286#define NILFS_NAME_LEN 255
 287
 288/*
 289 * Block size limitations
 290 */
 291#define NILFS_MIN_BLOCK_SIZE            1024
 292#define NILFS_MAX_BLOCK_SIZE            65536
 293
 294/*
 295 * The new version of the directory entry.  Since V0 structures are
 296 * stored in intel byte order, and the name_len field could never be
 297 * bigger than 255 chars, it's safe to reclaim the extra byte for the
 298 * file_type field.
 299 */
 300struct nilfs_dir_entry {
 301        __le64  inode;                  /* Inode number */
 302        __le16  rec_len;                /* Directory entry length */
 303        __u8    name_len;               /* Name length */
 304        __u8    file_type;              /* Dir entry type (file, dir, etc) */
 305        char    name[NILFS_NAME_LEN];   /* File name */
 306        char    pad;
 307};
 308
 309/*
 310 * NILFS directory file types.  Only the low 3 bits are used.  The
 311 * other bits are reserved for now.
 312 */
 313enum {
 314        NILFS_FT_UNKNOWN,
 315        NILFS_FT_REG_FILE,
 316        NILFS_FT_DIR,
 317        NILFS_FT_CHRDEV,
 318        NILFS_FT_BLKDEV,
 319        NILFS_FT_FIFO,
 320        NILFS_FT_SOCK,
 321        NILFS_FT_SYMLINK,
 322        NILFS_FT_MAX
 323};
 324
 325/*
 326 * NILFS_DIR_PAD defines the directory entries boundaries
 327 *
 328 * NOTE: It must be a multiple of 8
 329 */
 330#define NILFS_DIR_PAD                   8
 331#define NILFS_DIR_ROUND                 (NILFS_DIR_PAD - 1)
 332#define NILFS_DIR_REC_LEN(name_len)     (((name_len) + 12 + NILFS_DIR_ROUND) & \
 333                                        ~NILFS_DIR_ROUND)
 334#define NILFS_MAX_REC_LEN               ((1 << 16) - 1)
 335
 336/**
 337 * struct nilfs_finfo - file information
 338 * @fi_ino: inode number
 339 * @fi_cno: checkpoint number
 340 * @fi_nblocks: number of blocks (including intermediate blocks)
 341 * @fi_ndatablk: number of file data blocks
 342 */
 343struct nilfs_finfo {
 344        __le64 fi_ino;
 345        __le64 fi_cno;
 346        __le32 fi_nblocks;
 347        __le32 fi_ndatablk;
 348};
 349
 350/**
 351 * struct nilfs_binfo_v - information on a data block (except DAT)
 352 * @bi_vblocknr: virtual block number
 353 * @bi_blkoff: block offset
 354 */
 355struct nilfs_binfo_v {
 356        __le64 bi_vblocknr;
 357        __le64 bi_blkoff;
 358};
 359
 360/**
 361 * struct nilfs_binfo_dat - information on a DAT node block
 362 * @bi_blkoff: block offset
 363 * @bi_level: level
 364 * @bi_pad: padding
 365 */
 366struct nilfs_binfo_dat {
 367        __le64 bi_blkoff;
 368        __u8 bi_level;
 369        __u8 bi_pad[7];
 370};
 371
 372/**
 373 * union nilfs_binfo: block information
 374 * @bi_v: nilfs_binfo_v structure
 375 * @bi_dat: nilfs_binfo_dat structure
 376 */
 377union nilfs_binfo {
 378        struct nilfs_binfo_v bi_v;
 379        struct nilfs_binfo_dat bi_dat;
 380};
 381
 382/**
 383 * struct nilfs_segment_summary - segment summary header
 384 * @ss_datasum: checksum of data
 385 * @ss_sumsum: checksum of segment summary
 386 * @ss_magic: magic number
 387 * @ss_bytes: size of this structure in bytes
 388 * @ss_flags: flags
 389 * @ss_seq: sequence number
 390 * @ss_create: creation timestamp
 391 * @ss_next: next segment
 392 * @ss_nblocks: number of blocks
 393 * @ss_nfinfo: number of finfo structures
 394 * @ss_sumbytes: total size of segment summary in bytes
 395 * @ss_pad: padding
 396 * @ss_cno: checkpoint number
 397 */
 398struct nilfs_segment_summary {
 399        __le32 ss_datasum;
 400        __le32 ss_sumsum;
 401        __le32 ss_magic;
 402        __le16 ss_bytes;
 403        __le16 ss_flags;
 404        __le64 ss_seq;
 405        __le64 ss_create;
 406        __le64 ss_next;
 407        __le32 ss_nblocks;
 408        __le32 ss_nfinfo;
 409        __le32 ss_sumbytes;
 410        __le32 ss_pad;
 411        __le64 ss_cno;
 412        /* array of finfo structures */
 413};
 414
 415#define NILFS_SEGSUM_MAGIC      0x1eaffa11  /* segment summary magic number */
 416
 417/*
 418 * Segment summary flags
 419 */
 420#define NILFS_SS_LOGBGN 0x0001  /* begins a logical segment */
 421#define NILFS_SS_LOGEND 0x0002  /* ends a logical segment */
 422#define NILFS_SS_SR     0x0004  /* has super root */
 423#define NILFS_SS_SYNDT  0x0008  /* includes data only updates */
 424#define NILFS_SS_GC     0x0010  /* segment written for cleaner operation */
 425
 426/**
 427 * struct nilfs_btree_node - header of B-tree node block
 428 * @bn_flags: flags
 429 * @bn_level: level
 430 * @bn_nchildren: number of children
 431 * @bn_pad: padding
 432 */
 433struct nilfs_btree_node {
 434        __u8 bn_flags;
 435        __u8 bn_level;
 436        __le16 bn_nchildren;
 437        __le32 bn_pad;
 438};
 439
 440/* flags */
 441#define NILFS_BTREE_NODE_ROOT   0x01
 442
 443/* level */
 444#define NILFS_BTREE_LEVEL_DATA          0
 445#define NILFS_BTREE_LEVEL_NODE_MIN      (NILFS_BTREE_LEVEL_DATA + 1)
 446#define NILFS_BTREE_LEVEL_MAX           14      /* Max level (exclusive) */
 447
 448/**
 449 * struct nilfs_direct_node - header of built-in bmap array
 450 * @dn_flags: flags
 451 * @dn_pad: padding
 452 */
 453struct nilfs_direct_node {
 454        __u8 dn_flags;
 455        __u8 pad[7];
 456};
 457
 458/**
 459 * struct nilfs_palloc_group_desc - block group descriptor
 460 * @pg_nfrees: number of free entries in block group
 461 */
 462struct nilfs_palloc_group_desc {
 463        __le32 pg_nfrees;
 464};
 465
 466/**
 467 * struct nilfs_dat_entry - disk address translation entry
 468 * @de_blocknr: block number
 469 * @de_start: start checkpoint number
 470 * @de_end: end checkpoint number
 471 * @de_rsv: reserved for future use
 472 */
 473struct nilfs_dat_entry {
 474        __le64 de_blocknr;
 475        __le64 de_start;
 476        __le64 de_end;
 477        __le64 de_rsv;
 478};
 479
 480#define NILFS_MIN_DAT_ENTRY_SIZE        32
 481
 482/**
 483 * struct nilfs_snapshot_list - snapshot list
 484 * @ssl_next: next checkpoint number on snapshot list
 485 * @ssl_prev: previous checkpoint number on snapshot list
 486 */
 487struct nilfs_snapshot_list {
 488        __le64 ssl_next;
 489        __le64 ssl_prev;
 490};
 491
 492/**
 493 * struct nilfs_checkpoint - checkpoint structure
 494 * @cp_flags: flags
 495 * @cp_checkpoints_count: checkpoints count in a block
 496 * @cp_snapshot_list: snapshot list
 497 * @cp_cno: checkpoint number
 498 * @cp_create: creation timestamp
 499 * @cp_nblk_inc: number of blocks incremented by this checkpoint
 500 * @cp_inodes_count: inodes count
 501 * @cp_blocks_count: blocks count
 502 * @cp_ifile_inode: inode of ifile
 503 */
 504struct nilfs_checkpoint {
 505        __le32 cp_flags;
 506        __le32 cp_checkpoints_count;
 507        struct nilfs_snapshot_list cp_snapshot_list;
 508        __le64 cp_cno;
 509        __le64 cp_create;
 510        __le64 cp_nblk_inc;
 511        __le64 cp_inodes_count;
 512        __le64 cp_blocks_count;
 513
 514        /*
 515         * Do not change the byte offset of ifile inode.
 516         * To keep the compatibility of the disk format,
 517         * additional fields should be added behind cp_ifile_inode.
 518         */
 519        struct nilfs_inode cp_ifile_inode;
 520};
 521
 522#define NILFS_MIN_CHECKPOINT_SIZE       (64 + NILFS_MIN_INODE_SIZE)
 523
 524/* checkpoint flags */
 525enum {
 526        NILFS_CHECKPOINT_SNAPSHOT,
 527        NILFS_CHECKPOINT_INVALID,
 528        NILFS_CHECKPOINT_SKETCH,
 529        NILFS_CHECKPOINT_MINOR,
 530};
 531
 532#define NILFS_CHECKPOINT_FNS(flag, name)                                \
 533static inline void                                                      \
 534nilfs_checkpoint_set_##name(struct nilfs_checkpoint *cp)                \
 535{                                                                       \
 536        cp->cp_flags = cpu_to_le32(le32_to_cpu(cp->cp_flags) |          \
 537                                   (1UL << NILFS_CHECKPOINT_##flag));   \
 538}                                                                       \
 539static inline void                                                      \
 540nilfs_checkpoint_clear_##name(struct nilfs_checkpoint *cp)              \
 541{                                                                       \
 542        cp->cp_flags = cpu_to_le32(le32_to_cpu(cp->cp_flags) &          \
 543                                   ~(1UL << NILFS_CHECKPOINT_##flag));  \
 544}                                                                       \
 545static inline int                                                       \
 546nilfs_checkpoint_##name(const struct nilfs_checkpoint *cp)              \
 547{                                                                       \
 548        return !!(le32_to_cpu(cp->cp_flags) &                           \
 549                  (1UL << NILFS_CHECKPOINT_##flag));                    \
 550}
 551
 552NILFS_CHECKPOINT_FNS(SNAPSHOT, snapshot)
 553NILFS_CHECKPOINT_FNS(INVALID, invalid)
 554NILFS_CHECKPOINT_FNS(MINOR, minor)
 555
 556/**
 557 * struct nilfs_cpfile_header - checkpoint file header
 558 * @ch_ncheckpoints: number of checkpoints
 559 * @ch_nsnapshots: number of snapshots
 560 * @ch_snapshot_list: snapshot list
 561 */
 562struct nilfs_cpfile_header {
 563        __le64 ch_ncheckpoints;
 564        __le64 ch_nsnapshots;
 565        struct nilfs_snapshot_list ch_snapshot_list;
 566};
 567
 568#define NILFS_CPFILE_FIRST_CHECKPOINT_OFFSET                            \
 569        ((sizeof(struct nilfs_cpfile_header) +                          \
 570          sizeof(struct nilfs_checkpoint) - 1) /                        \
 571                        sizeof(struct nilfs_checkpoint))
 572
 573/**
 574 * struct nilfs_segment_usage - segment usage
 575 * @su_lastmod: last modified timestamp
 576 * @su_nblocks: number of blocks in segment
 577 * @su_flags: flags
 578 */
 579struct nilfs_segment_usage {
 580        __le64 su_lastmod;
 581        __le32 su_nblocks;
 582        __le32 su_flags;
 583};
 584
 585#define NILFS_MIN_SEGMENT_USAGE_SIZE    16
 586
 587/* segment usage flag */
 588enum {
 589        NILFS_SEGMENT_USAGE_ACTIVE,
 590        NILFS_SEGMENT_USAGE_DIRTY,
 591        NILFS_SEGMENT_USAGE_ERROR,
 592};
 593
 594#define NILFS_SEGMENT_USAGE_FNS(flag, name)                             \
 595static inline void                                                      \
 596nilfs_segment_usage_set_##name(struct nilfs_segment_usage *su)          \
 597{                                                                       \
 598        su->su_flags = cpu_to_le32(le32_to_cpu(su->su_flags) |          \
 599                                   (1UL << NILFS_SEGMENT_USAGE_##flag));\
 600}                                                                       \
 601static inline void                                                      \
 602nilfs_segment_usage_clear_##name(struct nilfs_segment_usage *su)        \
 603{                                                                       \
 604        su->su_flags =                                                  \
 605                cpu_to_le32(le32_to_cpu(su->su_flags) &                 \
 606                            ~(1UL << NILFS_SEGMENT_USAGE_##flag));      \
 607}                                                                       \
 608static inline int                                                       \
 609nilfs_segment_usage_##name(const struct nilfs_segment_usage *su)        \
 610{                                                                       \
 611        return !!(le32_to_cpu(su->su_flags) &                           \
 612                  (1UL << NILFS_SEGMENT_USAGE_##flag));                 \
 613}
 614
 615NILFS_SEGMENT_USAGE_FNS(ACTIVE, active)
 616NILFS_SEGMENT_USAGE_FNS(DIRTY, dirty)
 617NILFS_SEGMENT_USAGE_FNS(ERROR, error)
 618
 619static inline void
 620nilfs_segment_usage_set_clean(struct nilfs_segment_usage *su)
 621{
 622        su->su_lastmod = cpu_to_le64(0);
 623        su->su_nblocks = cpu_to_le32(0);
 624        su->su_flags = cpu_to_le32(0);
 625}
 626
 627static inline int
 628nilfs_segment_usage_clean(const struct nilfs_segment_usage *su)
 629{
 630        return !le32_to_cpu(su->su_flags);
 631}
 632
 633/**
 634 * struct nilfs_sufile_header - segment usage file header
 635 * @sh_ncleansegs: number of clean segments
 636 * @sh_ndirtysegs: number of dirty segments
 637 * @sh_last_alloc: last allocated segment number
 638 */
 639struct nilfs_sufile_header {
 640        __le64 sh_ncleansegs;
 641        __le64 sh_ndirtysegs;
 642        __le64 sh_last_alloc;
 643        /* ... */
 644};
 645
 646#define NILFS_SUFILE_FIRST_SEGMENT_USAGE_OFFSET                         \
 647        ((sizeof(struct nilfs_sufile_header) +                          \
 648          sizeof(struct nilfs_segment_usage) - 1) /                     \
 649                         sizeof(struct nilfs_segment_usage))
 650
 651#endif  /* _LINUX_NILFS2_ONDISK_H */
 652