include/linux/gfs2_ondisk.h

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
   4  *
   5  * This copyrighted material is made available to anyone wishing to use,
   6  * modify, copy, or redistribute it subject to the terms and conditions
   7  * of the GNU General Public License v.2.
   8  */
   9
  10 #ifndef __GFS2_ONDISK_DOT_H__
  11 #define __GFS2_ONDISK_DOT_H__
  12
  13 #include <linux/types.h>
  14
  15 #define GFS2_MAGIC              0x01161970
  16 #define GFS2_BASIC_BLOCK        512
  17 #define GFS2_BASIC_BLOCK_SHIFT  9
  18
  19 /* Lock numbers of the LM_TYPE_NONDISK type */
  20
  21 #define GFS2_MOUNT_LOCK         0
  22 #define GFS2_LIVE_LOCK          1
  23 #define GFS2_TRANS_LOCK         2
  24 #define GFS2_RENAME_LOCK        3
  25
  26 /* Format numbers for various metadata types */
  27
  28 #define GFS2_FORMAT_NONE        0
  29 #define GFS2_FORMAT_SB          100
  30 #define GFS2_FORMAT_RG          200
  31 #define GFS2_FORMAT_RB          300
  32 #define GFS2_FORMAT_DI          400
  33 #define GFS2_FORMAT_IN          500
  34 #define GFS2_FORMAT_LF          600
  35 #define GFS2_FORMAT_JD          700
  36 #define GFS2_FORMAT_LH          800
  37 #define GFS2_FORMAT_LD          900
  38 #define GFS2_FORMAT_LB          1000
  39 #define GFS2_FORMAT_EA          1600
  40 #define GFS2_FORMAT_ED          1700
  41 #define GFS2_FORMAT_QC          1400
  42 /* These are format numbers for entities contained in files */
  43 #define GFS2_FORMAT_RI          1100
  44 #define GFS2_FORMAT_DE          1200
  45 #define GFS2_FORMAT_QU          1500
  46 /* These are part of the superblock */
  47 #define GFS2_FORMAT_FS          1801
  48 #define GFS2_FORMAT_MULTI       1900
  49
  50 /*
  51  * An on-disk inode number
  52  */
  53
  54 struct gfs2_inum {
  55         __be64 no_formal_ino;
  56         __be64 no_addr;
  57 };
  58
  59 /*
  60  * Generic metadata head structure
  61  * Every inplace buffer logged in the journal must start with this.
  62  */
  63
  64 #define GFS2_METATYPE_NONE      0
  65 #define GFS2_METATYPE_SB        1
  66 #define GFS2_METATYPE_RG        2
  67 #define GFS2_METATYPE_RB        3
  68 #define GFS2_METATYPE_DI        4
  69 #define GFS2_METATYPE_IN        5
  70 #define GFS2_METATYPE_LF        6
  71 #define GFS2_METATYPE_JD        7
  72 #define GFS2_METATYPE_LH        8
  73 #define GFS2_METATYPE_LD        9
  74 #define GFS2_METATYPE_LB        12
  75 #define GFS2_METATYPE_EA        10
  76 #define GFS2_METATYPE_ED        11
  77 #define GFS2_METATYPE_QC        14
  78
  79 struct gfs2_meta_header {
  80         __be32 mh_magic;
  81         __be32 mh_type;
  82         __be64 __pad0;          /* Was generation number in gfs1 */
  83         __be32 mh_format;
  84         /* This union is to keep userspace happy */
  85         union {
  86                 __be32 mh_jid;          /* Was incarnation number in gfs1 */
  87                 __be32 __pad1;
  88         };
  89 };
  90
  91 /*
  92  * super-block structure
  93  *
  94  * It's probably good if SIZEOF_SB <= GFS2_BASIC_BLOCK (512 bytes)
  95  *
  96  * Order is important, need to be able to read old superblocks to do on-disk
  97  * version upgrades.
  98  */
  99
 100 /* Address of superblock in GFS2 basic blocks */
 101 #define GFS2_SB_ADDR            128
 102
 103 /* The lock number for the superblock (must be zero) */
 104 #define GFS2_SB_LOCK            0
 105
 106 /* Requirement:  GFS2_LOCKNAME_LEN % 8 == 0
 107    Includes: the fencing zero at the end */
 108 #define GFS2_LOCKNAME_LEN       64
 109
 110 struct gfs2_sb {
 111         struct gfs2_meta_header sb_header;
 112
 113         __be32 sb_fs_format;
 114         __be32 sb_multihost_format;
 115         __u32  __pad0;  /* Was superblock flags in gfs1 */
 116
 117         __be32 sb_bsize;
 118         __be32 sb_bsize_shift;
 119         __u32 __pad1;   /* Was journal segment size in gfs1 */
 120
 121         struct gfs2_inum sb_master_dir; /* Was jindex dinode in gfs1 */
 122         struct gfs2_inum __pad2; /* Was rindex dinode in gfs1 */
 123         struct gfs2_inum sb_root_dir;
 124
 125         char sb_lockproto[GFS2_LOCKNAME_LEN];
 126         char sb_locktable[GFS2_LOCKNAME_LEN];
 127
 128         struct gfs2_inum __pad3; /* Was quota inode in gfs1 */
 129         struct gfs2_inum __pad4; /* Was licence inode in gfs1 */
 130 #define GFS2_HAS_UUID 1
 131         __u8 sb_uuid[16]; /* The UUID, maybe 0 for backwards compat */
 132 };
 133
 134 /*
 135  * resource index structure
 136  */
 137
 138 struct gfs2_rindex {
 139         __be64 ri_addr; /* grp block disk address */
 140         __be32 ri_length;       /* length of rgrp header in fs blocks */
 141         __u32 __pad;
 142
 143         __be64 ri_data0;        /* first data location */
 144         __be32 ri_data; /* num of data blocks in rgrp */
 145
 146         __be32 ri_bitbytes;     /* number of bytes in data bitmaps */
 147
 148         __u8 ri_reserved[64];
 149 };
 150
 151 /*
 152  * resource group header structure
 153  */
 154
 155 /* Number of blocks per byte in rgrp */
 156 #define GFS2_NBBY               4
 157 #define GFS2_BIT_SIZE           2
 158 #define GFS2_BIT_MASK           0x00000003
 159
 160 #define GFS2_BLKST_FREE         0
 161 #define GFS2_BLKST_USED         1
 162 #define GFS2_BLKST_UNLINKED     2
 163 #define GFS2_BLKST_DINODE       3
 164
 165 #define GFS2_RGF_JOURNAL        0x00000001
 166 #define GFS2_RGF_METAONLY       0x00000002
 167 #define GFS2_RGF_DATAONLY       0x00000004
 168 #define GFS2_RGF_NOALLOC        0x00000008
 169
 170 struct gfs2_rgrp {
 171         struct gfs2_meta_header rg_header;
 172
 173         __be32 rg_flags;
 174         __be32 rg_free;
 175         __be32 rg_dinodes;
 176         __be32 __pad;
 177         __be64 rg_igeneration;
 178
 179         __u8 rg_reserved[80]; /* Several fields from gfs1 now reserved */
 180 };
 181
 182 /*
 183  * quota linked list: user quotas and group quotas form two separate
 184  * singly linked lists. ll_next stores uids or gids of next quotas in the
 185  * linked list.
 186
 187 Given the uid/gid, how to calculate the quota file offsets for the corresponding
 188 gfs2_quota structures on disk:
 189
 190 for user quotas, given uid,
 191 offset = uid * sizeof(struct gfs2_quota);
 192
 193 for group quotas, given gid,
 194 offset = (gid * sizeof(struct gfs2_quota)) + sizeof(struct gfs2_quota);
 195
 196
 197   uid:0   gid:0       uid:12   gid:12      uid:17   gid:17     uid:5142 gid:5142
 198 +-------+-------+    +-------+-------+    +-------+- - - -+    +- - - -+-------+
 199 | valid | valid | :: | valid | valid | :: | valid | inval | :: | inval | valid |
 200 +-------+-------+    +-------+-------+    +-------+- - - -+    +- - - -+-------+
 201 next:12   next:12    next:17 next:5142    next:NULL                    next:NULL
 202     |       |            |       |            |<-- user quota list         |
 203      \______|___________/ \______|___________/         group quota list -->|
 204             |                    |                                         |
 205              \__________________/ \_______________________________________/
 206
 207 */
 208
 209 /*
 210  * quota structure
 211  */
 212
 213 struct gfs2_quota {
 214         __be64 qu_limit;
 215         __be64 qu_warn;
 216         __be64 qu_value;
 217         __be32 qu_ll_next; /* location of next quota in list */
 218         __u8 qu_reserved[60];
 219 };
 220
 221 /*
 222  * dinode structure
 223  */
 224
 225 #define GFS2_MAX_META_HEIGHT    10
 226 #define GFS2_DIR_MAX_DEPTH      17
 227
 228 #define DT2IF(dt) (((dt) << 12) & S_IFMT)
 229 #define IF2DT(sif) (((sif) & S_IFMT) >> 12)
 230
 231 enum {
 232         gfs2fl_Jdata            = 0,
 233         gfs2fl_ExHash           = 1,
 234         gfs2fl_Unused           = 2,
 235         gfs2fl_EaIndirect       = 3,
 236         gfs2fl_Directio         = 4,
 237         gfs2fl_Immutable        = 5,
 238         gfs2fl_AppendOnly       = 6,
 239         gfs2fl_NoAtime          = 7,
 240         gfs2fl_Sync             = 8,
 241         gfs2fl_System           = 9,
 242         gfs2fl_TruncInProg      = 29,
 243         gfs2fl_InheritDirectio  = 30,
 244         gfs2fl_InheritJdata     = 31,
 245 };
 246
 247 /* Dinode flags */
 248 #define GFS2_DIF_JDATA                  0x00000001
 249 #define GFS2_DIF_EXHASH                 0x00000002
 250 #define GFS2_DIF_UNUSED                 0x00000004  /* only in gfs1 */
 251 #define GFS2_DIF_EA_INDIRECT            0x00000008
 252 #define GFS2_DIF_DIRECTIO               0x00000010
 253 #define GFS2_DIF_IMMUTABLE              0x00000020
 254 #define GFS2_DIF_APPENDONLY             0x00000040
 255 #define GFS2_DIF_NOATIME                0x00000080
 256 #define GFS2_DIF_SYNC                   0x00000100
 257 #define GFS2_DIF_SYSTEM                 0x00000200 /* New in gfs2 */
 258 #define GFS2_DIF_TRUNC_IN_PROG          0x20000000 /* New in gfs2 */
 259 #define GFS2_DIF_INHERIT_DIRECTIO       0x40000000
 260 #define GFS2_DIF_INHERIT_JDATA          0x80000000
 261
 262 struct gfs2_dinode {
 263         struct gfs2_meta_header di_header;
 264
 265         struct gfs2_inum di_num;
 266
 267         __be32 di_mode; /* mode of file */
 268         __be32 di_uid;  /* owner's user id */
 269         __be32 di_gid;  /* owner's group id */
 270         __be32 di_nlink;        /* number of links to this file */
 271         __be64 di_size; /* number of bytes in file */
 272         __be64 di_blocks;       /* number of blocks in file */
 273         __be64 di_atime;        /* time last accessed */
 274         __be64 di_mtime;        /* time last modified */
 275         __be64 di_ctime;        /* time last changed */
 276         __be32 di_major;        /* device major number */
 277         __be32 di_minor;        /* device minor number */
 278
 279         /* This section varies from gfs1. Padding added to align with
 280          * remainder of dinode
 281          */
 282         __be64 di_goal_meta;    /* rgrp to alloc from next */
 283         __be64 di_goal_data;    /* data block goal */
 284         __be64 di_generation;   /* generation number for NFS */
 285
 286         __be32 di_flags;        /* GFS2_DIF_... */
 287         __be32 di_payload_format;  /* GFS2_FORMAT_... */
 288         __u16 __pad1;   /* Was ditype in gfs1 */
 289         __be16 di_height;       /* height of metadata */
 290         __u32 __pad2;   /* Unused incarnation number from gfs1 */
 291
 292         /* These only apply to directories  */
 293         __u16 __pad3;   /* Padding */
 294         __be16 di_depth;        /* Number of bits in the table */
 295         __be32 di_entries;      /* The number of entries in the directory */
 296
 297         struct gfs2_inum __pad4; /* Unused even in current gfs1 */
 298
 299         __be64 di_eattr;        /* extended attribute block number */
 300         __be32 di_atime_nsec;   /* nsec portion of atime */
 301         __be32 di_mtime_nsec;   /* nsec portion of mtime */
 302         __be32 di_ctime_nsec;   /* nsec portion of ctime */
 303
 304         __u8 di_reserved[44];
 305 };
 306
 307 /*
 308  * directory structure - many of these per directory file
 309  */
 310
 311 #define GFS2_FNAMESIZE          255
 312 #define GFS2_DIRENT_SIZE(name_len) ((sizeof(struct gfs2_dirent) + (name_len) + 7) & ~7)
 313
 314 struct gfs2_dirent {
 315         struct gfs2_inum de_inum;
 316         __be32 de_hash;
 317         __be16 de_rec_len;
 318         __be16 de_name_len;
 319         __be16 de_type;
 320         __u8 __pad[14];
 321 };
 322
 323 /*
 324  * Header of leaf directory nodes
 325  */
 326
 327 struct gfs2_leaf {
 328         struct gfs2_meta_header lf_header;
 329
 330         __be16 lf_depth;                /* Depth of leaf */
 331         __be16 lf_entries;              /* Number of dirents in leaf */
 332         __be32 lf_dirent_format;        /* Format of the dirents */
 333         __be64 lf_next;                 /* Next leaf, if overflow */
 334
 335         __u8 lf_reserved[64];
 336 };
 337
 338 /*
 339  * Extended attribute header format
 340  *
 341  * This works in a similar way to dirents. There is a fixed size header
 342  * followed by a variable length section made up of the name and the
 343  * associated data. In the case of a "stuffed" entry, the value is
 344  * inline directly after the name, the ea_num_ptrs entry will be
 345  * zero in that case. For non-"stuffed" entries, there will be
 346  * a set of pointers (aligned to 8 byte boundary) to the block(s)
 347  * containing the value.
 348  *
 349  * The blocks containing the values and the blocks containing the
 350  * extended attribute headers themselves all start with the common
 351  * metadata header. Each inode, if it has extended attributes, will
 352  * have either a single block containing the extended attribute headers
 353  * or a single indirect block pointing to blocks containing the
 354  * extended attribure headers.
 355  *
 356  * The maximim size of the data part of an extended attribute is 64k
 357  * so the number of blocks required depends upon block size. Since the
 358  * block size also determines the number of pointers in an indirect
 359  * block, its a fairly complicated calculation to work out the maximum
 360  * number of blocks that an inode may have relating to extended attributes.
 361  *
 362  */
 363
 364 #define GFS2_EA_MAX_NAME_LEN    255
 365 #define GFS2_EA_MAX_DATA_LEN    65536
 366
 367 #define GFS2_EATYPE_UNUSED      0
 368 #define GFS2_EATYPE_USR         1
 369 #define GFS2_EATYPE_SYS         2
 370 #define GFS2_EATYPE_SECURITY    3
 371
 372 #define GFS2_EATYPE_LAST        3
 373 #define GFS2_EATYPE_VALID(x)    ((x) <= GFS2_EATYPE_LAST)
 374
 375 #define GFS2_EAFLAG_LAST        0x01    /* last ea in block */
 376
 377 struct gfs2_ea_header {
 378         __be32 ea_rec_len;
 379         __be32 ea_data_len;
 380         __u8 ea_name_len;       /* no NULL pointer after the string */
 381         __u8 ea_type;           /* GFS2_EATYPE_... */
 382         __u8 ea_flags;          /* GFS2_EAFLAG_... */
 383         __u8 ea_num_ptrs;
 384         __u32 __pad;
 385 };
 386
 387 /*
 388  * Log header structure
 389  */
 390
 391 #define GFS2_LOG_HEAD_UNMOUNT   0x00000001      /* log is clean */
 392
 393 struct gfs2_log_header {
 394         struct gfs2_meta_header lh_header;
 395
 396         __be64 lh_sequence;     /* Sequence number of this transaction */
 397         __be32 lh_flags;        /* GFS2_LOG_HEAD_... */
 398         __be32 lh_tail;         /* Block number of log tail */
 399         __be32 lh_blkno;
 400         __be32 lh_hash;
 401 };
 402
 403 /*
 404  * Log type descriptor
 405  */
 406
 407 #define GFS2_LOG_DESC_METADATA  300
 408 /* ld_data1 is the number of metadata blocks in the descriptor.
 409    ld_data2 is unused. */
 410
 411 #define GFS2_LOG_DESC_REVOKE    301
 412 /* ld_data1 is the number of revoke blocks in the descriptor.
 413    ld_data2 is unused. */
 414
 415 #define GFS2_LOG_DESC_JDATA     302
 416 /* ld_data1 is the number of data blocks in the descriptor.
 417    ld_data2 is unused. */
 418
 419 struct gfs2_log_descriptor {
 420         struct gfs2_meta_header ld_header;
 421
 422         __be32 ld_type;         /* GFS2_LOG_DESC_... */
 423         __be32 ld_length;       /* Number of buffers in this chunk */
 424         __be32 ld_data1;        /* descriptor-specific field */
 425         __be32 ld_data2;        /* descriptor-specific field */
 426
 427         __u8 ld_reserved[32];
 428 };
 429
 430 /*
 431  * Inum Range
 432  * Describe a range of formal inode numbers allocated to
 433  * one machine to assign to inodes.
 434  */
 435
 436 #define GFS2_INUM_QUANTUM       1048576
 437
 438 struct gfs2_inum_range {
 439         __be64 ir_start;
 440         __be64 ir_length;
 441 };
 442
 443 /*
 444  * Statfs change
 445  * Describes an change to the pool of free and allocated
 446  * blocks.
 447  */
 448
 449 struct gfs2_statfs_change {
 450         __be64 sc_total;
 451         __be64 sc_free;
 452         __be64 sc_dinodes;
 453 };
 454
 455 /*
 456  * Quota change
 457  * Describes an allocation change for a particular
 458  * user or group.
 459  */
 460
 461 #define GFS2_QCF_USER           0x00000001
 462
 463 struct gfs2_quota_change {
 464         __be64 qc_change;
 465         __be32 qc_flags;        /* GFS2_QCF_... */
 466         __be32 qc_id;
 467 };
 468
 469 struct gfs2_quota_lvb {
 470         __be32 qb_magic;
 471         __u32 __pad;
 472         __be64 qb_limit;      /* Hard limit of # blocks to alloc */
 473         __be64 qb_warn;       /* Warn user when alloc is above this # */
 474         __be64 qb_value;       /* Current # blocks allocated */
 475 };
 476
 477 #endif /* __GFS2_ONDISK_DOT_H__ */