fs.h revision 1.47
1/* $NetBSD: fs.h,v 1.47 2007/09/24 16:20:50 pooka Exp $ */ 2 3/* 4 * Copyright (c) 1982, 1986, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)fs.h 8.13 (Berkeley) 3/21/95 32 */ 33 34#ifndef _UFS_FFS_FS_H_ 35#define _UFS_FFS_FS_H_ 36 37/* 38 * Each disk drive contains some number of file systems. 39 * A file system consists of a number of cylinder groups. 40 * Each cylinder group has inodes and data. 41 * 42 * A file system is described by its super-block, which in turn 43 * describes the cylinder groups. The super-block is critical 44 * data and is replicated in each cylinder group to protect against 45 * catastrophic loss. This is done at `newfs' time and the critical 46 * super-block data does not change, so the copies need not be 47 * referenced further unless disaster strikes. 48 * 49 * For file system fs, the offsets of the various blocks of interest 50 * are given in the super block as: 51 * [fs->fs_sblkno] Super-block 52 * [fs->fs_cblkno] Cylinder group block 53 * [fs->fs_iblkno] Inode blocks 54 * [fs->fs_dblkno] Data blocks 55 * The beginning of cylinder group cg in fs, is given by 56 * the ``cgbase(fs, cg)'' macro. 57 * 58 * Depending on the architecture and the media, the superblock may 59 * reside in any one of four places. For tiny media where every block 60 * counts, it is placed at the very front of the partition. Historically, 61 * UFS1 placed it 8K from the front to leave room for the disk label and 62 * a small bootstrap. For UFS2 it got moved to 64K from the front to leave 63 * room for the disk label and a bigger bootstrap, and for really piggy 64 * systems we check at 256K from the front if the first three fail. In 65 * all cases the size of the superblock will be SBLOCKSIZE. All values are 66 * given in byte-offset form, so they do not imply a sector size. The 67 * SBLOCKSEARCH specifies the order in which the locations should be searched. 68 * 69 * Unfortunately the UFS2/FFSv2 change was done without adequate consideration 70 * of backward compatibility. In particular 'newfs' for a FFSv2 partition 71 * must overwrite any old FFSv1 superblock at 8k, and preferrably as many 72 * of the alternates as it can find - otherwise attempting to mount on a 73 * system that only supports FFSv1 is likely to succeed!. 74 * For a small FFSv1 filesystem, an old FFSv2 superblock can be left on 75 * the disk, and a system that tries to find an FFSv2 filesystem in preference 76 * to and FFSv1 one (as NetBSD does) can mount the old FFSv2 filesystem. 77 * As a added bonus, the 'first alternate' superblock of a FFSv1 filesystem 78 * with 64k blocks is at 64k - just where the code looks first when playing 79 * 'hunt the superblock'. 80 * 81 * The ffsv2 superblock layout (which might contain an ffsv1 filesystem) 82 * can be detected by checking for sb->fs_old_flags & FS_FLAGS_UPDATED. 83 * This is the default suberblock type for NetBSD since ffsv2 support was added. 84 */ 85#define BBSIZE 8192 86#define BBOFF ((off_t)(0)) 87#define BBLOCK ((daddr_t)(0)) 88 89#define SBLOCK_FLOPPY 0 90#define SBLOCK_UFS1 8192 91#define SBLOCK_UFS2 65536 92#define SBLOCK_PIGGY 262144 93#define SBLOCKSIZE 8192 94/* 95 * NB: Do not, under any circumstances, look for an ffsv1 filesystem at 96 * SBLOCK_UFS2. Doing so will find the wrong superblock for filesystems 97 * with a 64k block size. 98 */ 99#define SBLOCKSEARCH \ 100 { SBLOCK_UFS2, SBLOCK_UFS1, SBLOCK_FLOPPY, SBLOCK_PIGGY, -1 } 101 102/* 103 * Max number of fragments per block. This value is NOT tweakable. 104 */ 105#define MAXFRAG 8 106 107 108 109/* 110 * Addresses stored in inodes are capable of addressing fragments 111 * of `blocks'. File system blocks of at most size MAXBSIZE can 112 * be optionally broken into 2, 4, or 8 pieces, each of which is 113 * addressable; these pieces may be DEV_BSIZE, or some multiple of 114 * a DEV_BSIZE unit. 115 * 116 * Large files consist of exclusively large data blocks. To avoid 117 * undue wasted disk space, the last data block of a small file may be 118 * allocated as only as many fragments of a large block as are 119 * necessary. The file system format retains only a single pointer 120 * to such a fragment, which is a piece of a single large block that 121 * has been divided. The size of such a fragment is determinable from 122 * information in the inode, using the ``blksize(fs, ip, lbn)'' macro. 123 * 124 * The file system records space availability at the fragment level; 125 * to determine block availability, aligned fragments are examined. 126 */ 127 128/* 129 * MINBSIZE is the smallest allowable block size. 130 * In order to insure that it is possible to create files of size 131 * 2^32 with only two levels of indirection, MINBSIZE is set to 4096. 132 * MINBSIZE must be big enough to hold a cylinder group block, 133 * thus changes to (struct cg) must keep its size within MINBSIZE. 134 * Note that super blocks are always of size SBSIZE, 135 * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE. 136 */ 137#define MINBSIZE 4096 138 139/* 140 * The path name on which the file system is mounted is maintained 141 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in 142 * the super block for this name. 143 */ 144#define MAXMNTLEN 468 145 146/* 147 * The volume name for this filesystem is maintained in fs_volname. 148 * MAXVOLLEN defines the length of the buffer allocated. 149 * This space used to be part of of fs_fsmnt. 150 */ 151#define MAXVOLLEN 32 152 153/* 154 * There is a 128-byte region in the superblock reserved for in-core 155 * pointers to summary information. Originally this included an array 156 * of pointers to blocks of struct csum; now there are just four 157 * pointers and the remaining space is padded with fs_ocsp[]. 158 * NOCSPTRS determines the size of this padding. One pointer (fs_csp) 159 * is taken away to point to a contiguous array of struct csum for 160 * all cylinder groups; a second (fs_maxcluster) points to an array 161 * of cluster sizes that is computed as cylinder groups are inspected; 162 * the third (fs_contigdirs) points to an array that tracks the 163 * creation of new directories; and the fourth (fs_active) is used 164 * by snapshots. 165 */ 166#define NOCSPTRS ((128 / sizeof(void *)) - 4) 167 168/* 169 * A summary of contiguous blocks of various sizes is maintained 170 * in each cylinder group. Normally this is set by the initial 171 * value of fs_maxcontig. To conserve space, a maximum summary size 172 * is set by FS_MAXCONTIG. 173 */ 174#define FS_MAXCONTIG 16 175 176/* 177 * The maximum number of snapshot nodes that can be associated 178 * with each filesystem. This limit affects only the number of 179 * snapshot files that can be recorded within the superblock so 180 * that they can be found when the filesystem is mounted. However, 181 * maintaining too many will slow the filesystem performance, so 182 * having this limit is a good idea. 183 */ 184#define FSMAXSNAP 20 185 186/* 187 * Used to identify special blocks in snapshots: 188 * 189 * BLK_NOCOPY - A block that was unallocated at the time the snapshot 190 * was taken, hence does not need to be copied when written. 191 * BLK_SNAP - A block held by another snapshot that is not needed by this 192 * snapshot. When the other snapshot is freed, the BLK_SNAP entries 193 * are converted to BLK_NOCOPY. These are needed to allow fsck to 194 * identify blocks that are in use by other snapshots (which are 195 * expunged from this snapshot). 196 */ 197#define BLK_NOCOPY ((daddr_t)(1)) 198#define BLK_SNAP ((daddr_t)(2)) 199 200/* 201 * MINFREE gives the minimum acceptable percentage of file system 202 * blocks which may be free. If the freelist drops below this level 203 * only the superuser may continue to allocate blocks. This may 204 * be set to 0 if no reserve of free blocks is deemed necessary, 205 * however throughput drops by fifty percent if the file system 206 * is run at between 95% and 100% full; thus the minimum default 207 * value of fs_minfree is 5%. However, to get good clustering 208 * performance, 10% is a better choice. This value is used only 209 * when creating a file system and can be overriden from the 210 * command line. By default we choose to optimize for time. 211 */ 212#define MINFREE 5 213#define DEFAULTOPT FS_OPTTIME 214 215/* 216 * Grigoriy Orlov <gluk@ptci.ru> has done some extensive work to fine 217 * tune the layout preferences for directories within a filesystem. 218 * His algorithm can be tuned by adjusting the following parameters 219 * which tell the system the average file size and the average number 220 * of files per directory. These defaults are well selected for typical 221 * filesystems, but may need to be tuned for odd cases like filesystems 222 * being used for squid caches or news spools. 223 */ 224#define AVFILESIZ 16384 /* expected average file size */ 225#define AFPDIR 64 /* expected number of files per directory */ 226 227/* 228 * Per cylinder group information; summarized in blocks allocated 229 * from first cylinder group data blocks. These blocks have to be 230 * read in from fs_csaddr (size fs_cssize) in addition to the 231 * super block. 232 */ 233struct csum { 234 int32_t cs_ndir; /* number of directories */ 235 int32_t cs_nbfree; /* number of free blocks */ 236 int32_t cs_nifree; /* number of free inodes */ 237 int32_t cs_nffree; /* number of free frags */ 238}; 239 240struct csum_total { 241 int64_t cs_ndir; /* number of directories */ 242 int64_t cs_nbfree; /* number of free blocks */ 243 int64_t cs_nifree; /* number of free inodes */ 244 int64_t cs_nffree; /* number of free frags */ 245 int64_t cs_spare[4]; /* future expansion */ 246}; 247 248 249/* 250 * Super block for an FFS file system in memory. 251 */ 252struct fs { 253 int32_t fs_firstfield; /* historic file system linked list, */ 254 int32_t fs_unused_1; /* used for incore super blocks */ 255 int32_t fs_sblkno; /* addr of super-block in filesys */ 256 int32_t fs_cblkno; /* offset of cyl-block in filesys */ 257 int32_t fs_iblkno; /* offset of inode-blocks in filesys */ 258 int32_t fs_dblkno; /* offset of first data after cg */ 259 int32_t fs_old_cgoffset; /* cylinder group offset in cylinder */ 260 int32_t fs_old_cgmask; /* used to calc mod fs_ntrak */ 261 int32_t fs_old_time; /* last time written */ 262 int32_t fs_old_size; /* number of blocks in fs */ 263 int32_t fs_old_dsize; /* number of data blocks in fs */ 264 int32_t fs_ncg; /* number of cylinder groups */ 265 int32_t fs_bsize; /* size of basic blocks in fs */ 266 int32_t fs_fsize; /* size of frag blocks in fs */ 267 int32_t fs_frag; /* number of frags in a block in fs */ 268/* these are configuration parameters */ 269 int32_t fs_minfree; /* minimum percentage of free blocks */ 270 int32_t fs_old_rotdelay; /* num of ms for optimal next block */ 271 int32_t fs_old_rps; /* disk revolutions per second */ 272/* these fields can be computed from the others */ 273 int32_t fs_bmask; /* ``blkoff'' calc of blk offsets */ 274 int32_t fs_fmask; /* ``fragoff'' calc of frag offsets */ 275 int32_t fs_bshift; /* ``lblkno'' calc of logical blkno */ 276 int32_t fs_fshift; /* ``numfrags'' calc number of frags */ 277/* these are configuration parameters */ 278 int32_t fs_maxcontig; /* max number of contiguous blks */ 279 int32_t fs_maxbpg; /* max number of blks per cyl group */ 280/* these fields can be computed from the others */ 281 int32_t fs_fragshift; /* block to frag shift */ 282 int32_t fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */ 283 int32_t fs_sbsize; /* actual size of super block */ 284 int32_t fs_spare1[2]; /* old fs_csmask */ 285 /* old fs_csshift */ 286 int32_t fs_nindir; /* value of NINDIR */ 287 int32_t fs_inopb; /* value of INOPB */ 288 int32_t fs_old_nspf; /* value of NSPF */ 289/* yet another configuration parameter */ 290 int32_t fs_optim; /* optimization preference, see below */ 291/* these fields are derived from the hardware */ 292 int32_t fs_old_npsect; /* # sectors/track including spares */ 293 int32_t fs_old_interleave; /* hardware sector interleave */ 294 int32_t fs_old_trackskew; /* sector 0 skew, per track */ 295/* fs_id takes the space of the unused fs_headswitch and fs_trkseek fields */ 296 int32_t fs_id[2]; /* unique file system id */ 297/* sizes determined by number of cylinder groups and their sizes */ 298 int32_t fs_old_csaddr; /* blk addr of cyl grp summary area */ 299 int32_t fs_cssize; /* size of cyl grp summary area */ 300 int32_t fs_cgsize; /* cylinder group size */ 301/* these fields are derived from the hardware */ 302 int32_t fs_spare2; /* old fs_ntrak */ 303 int32_t fs_old_nsect; /* sectors per track */ 304 int32_t fs_old_spc; /* sectors per cylinder */ 305 int32_t fs_old_ncyl; /* cylinders in file system */ 306 int32_t fs_old_cpg; /* cylinders per group */ 307 int32_t fs_ipg; /* inodes per group */ 308 int32_t fs_fpg; /* blocks per group * fs_frag */ 309/* this data must be re-computed after crashes */ 310 struct csum fs_old_cstotal; /* cylinder summary information */ 311/* these fields are cleared at mount time */ 312 int8_t fs_fmod; /* super block modified flag */ 313 int8_t fs_clean; /* file system is clean flag */ 314 int8_t fs_ronly; /* mounted read-only flag */ 315 uint8_t fs_old_flags; /* see FS_ flags below */ 316 u_char fs_fsmnt[MAXMNTLEN]; /* name mounted on */ 317 u_char fs_volname[MAXVOLLEN]; /* volume name */ 318 uint64_t fs_swuid; /* system-wide uid */ 319 int32_t fs_pad; 320/* these fields retain the current block allocation info */ 321 int32_t fs_cgrotor; /* last cg searched (UNUSED) */ 322 void *fs_ocsp[NOCSPTRS]; /* padding; was list of fs_cs buffers */ 323 u_int8_t *fs_contigdirs; /* # of contiguously allocated dirs */ 324 struct csum *fs_csp; /* cg summary info buffer for fs_cs */ 325 int32_t *fs_maxcluster; /* max cluster in each cyl group */ 326 u_char *fs_active; /* used by snapshots to track fs */ 327 int32_t fs_old_cpc; /* cyl per cycle in postbl */ 328/* this area is otherwise allocated unless fs_old_flags & FS_FLAGS_UPDATED */ 329 int32_t fs_maxbsize; /* maximum blocking factor permitted */ 330 int64_t fs_sparecon64[17]; /* old rotation block list head */ 331 int64_t fs_sblockloc; /* byte offset of standard superblock */ 332 struct csum_total fs_cstotal; /* cylinder summary information */ 333 int64_t fs_time; /* last time written */ 334 int64_t fs_size; /* number of blocks in fs */ 335 int64_t fs_dsize; /* number of data blocks in fs */ 336 int64_t fs_csaddr; /* blk addr of cyl grp summary area */ 337 int64_t fs_pendingblocks; /* blocks in process of being freed */ 338 int32_t fs_pendinginodes; /* inodes in process of being freed */ 339 int32_t fs_snapinum[FSMAXSNAP];/* list of snapshot inode numbers */ 340/* back to stuff that has been around a while */ 341 int32_t fs_avgfilesize; /* expected average file size */ 342 int32_t fs_avgfpdir; /* expected # of files per directory */ 343 int32_t fs_save_cgsize; /* save real cg size to use fs_bsize */ 344 int32_t fs_sparecon32[26]; /* reserved for future constants */ 345 uint32_t fs_flags; /* see FS_ flags below */ 346/* back to stuff that has been around a while (again) */ 347 int32_t fs_contigsumsize; /* size of cluster summary array */ 348 int32_t fs_maxsymlinklen; /* max length of an internal symlink */ 349 int32_t fs_old_inodefmt; /* format of on-disk inodes */ 350 u_int64_t fs_maxfilesize; /* maximum representable file size */ 351 int64_t fs_qbmask; /* ~fs_bmask for use with 64-bit size */ 352 int64_t fs_qfmask; /* ~fs_fmask for use with 64-bit size */ 353 int32_t fs_state; /* validate fs_clean field (UNUSED) */ 354 int32_t fs_old_postblformat; /* format of positional layout tables */ 355 int32_t fs_old_nrpos; /* number of rotational positions */ 356 int32_t fs_spare5[2]; /* old fs_postbloff */ 357 /* old fs_rotbloff */ 358 int32_t fs_magic; /* magic number */ 359}; 360 361#define fs_old_postbloff fs_spare5[0] 362#define fs_old_rotbloff fs_spare5[1] 363#define fs_old_postbl_start fs_maxbsize 364#define fs_old_headswitch fs_id[0] 365#define fs_old_trkseek fs_id[1] 366#define fs_old_csmask fs_spare1[0] 367#define fs_old_csshift fs_spare1[1] 368 369#define FS_42POSTBLFMT -1 /* 4.2BSD rotational table format */ 370#define FS_DYNAMICPOSTBLFMT 1 /* dynamic rotational table format */ 371 372#define old_fs_postbl(fs_, cylno, opostblsave) \ 373 ((((fs_)->fs_old_postblformat == FS_42POSTBLFMT) || \ 374 ((fs_)->fs_old_postbloff == offsetof(struct fs, fs_old_postbl_start))) \ 375 ? ((int16_t *)(opostblsave) + (cylno) * (fs_)->fs_old_nrpos) \ 376 : ((int16_t *)((uint8_t *)(fs_) + \ 377 (fs_)->fs_old_postbloff) + (cylno) * (fs_)->fs_old_nrpos)) 378#define old_fs_rotbl(fs) \ 379 (((fs)->fs_old_postblformat == FS_42POSTBLFMT) \ 380 ? ((uint8_t *)(&(fs)->fs_magic+1)) \ 381 : ((uint8_t *)((uint8_t *)(fs) + (fs)->fs_old_rotbloff))) 382 383/* 384 * File system identification 385 */ 386#define FS_UFS1_MAGIC 0x011954 /* UFS1 fast file system magic number */ 387#define FS_UFS2_MAGIC 0x19540119 /* UFS2 fast file system magic number */ 388#define FS_UFS1_MAGIC_SWAPPED 0x54190100 389#define FS_UFS2_MAGIC_SWAPPED 0x19015419 390#define FS_OKAY 0x7c269d38 /* superblock checksum */ 391#define FS_42INODEFMT -1 /* 4.2BSD inode format */ 392#define FS_44INODEFMT 2 /* 4.4BSD inode format */ 393 394/* 395 * File system clean flags 396 */ 397#define FS_ISCLEAN 0x01 398#define FS_WASCLEAN 0x02 399 400/* 401 * Preference for optimization. 402 */ 403#define FS_OPTTIME 0 /* minimize allocation time */ 404#define FS_OPTSPACE 1 /* minimize disk fragmentation */ 405 406/* 407 * File system flags 408 */ 409#define FS_UNCLEAN 0x01 /* file system not clean at mount (unused) */ 410#define FS_DOSOFTDEP 0x02 /* file system using soft dependencies */ 411#define FS_NEEDSFSCK 0x04 /* needs sync fsck (FreeBSD compat, unused) */ 412#define FS_INDEXDIRS 0x08 /* kernel supports indexed directories */ 413#define FS_ACLS 0x10 /* file system has ACLs enabled */ 414#define FS_MULTILABEL 0x20 /* file system is MAC multi-label */ 415#define FS_FLAGS_UPDATED 0x80 /* flags have been moved to new location */ 416 417/* 418 * File system internal flags, also in fs_flags. 419 * (Pick highest number to avoid conflicts with others) 420 */ 421#define FS_SWAPPED 0x80000000 /* file system is endian swapped */ 422#define FS_INTERNAL 0x80000000 /* mask for internal flags */ 423 424/* 425 * Macros to access bits in the fs_active array. 426 */ 427#define ACTIVECG_SET(fs, cg) \ 428 do { \ 429 if ((fs)->fs_active != NULL) \ 430 setbit((fs)->fs_active, (cg)); \ 431 } while (/*CONSTCOND*/ 0) 432#define ACTIVECG_CLR(fs, cg) \ 433 do { \ 434 if ((fs)->fs_active != NULL) \ 435 clrbit((fs)->fs_active, (cg)); \ 436 } while (/*CONSTCOND*/ 0) 437#define ACTIVECG_ISSET(fs, cg) \ 438 ((fs)->fs_active != NULL && isset((fs)->fs_active, (cg))) 439 440/* 441 * The size of a cylinder group is calculated by CGSIZE. The maximum size 442 * is limited by the fact that cylinder groups are at most one block. 443 * Its size is derived from the size of the maps maintained in the 444 * cylinder group and the (struct cg) size. 445 */ 446#define CGSIZE_IF(fs, ipg, fpg) \ 447 /* base cg */ (sizeof(struct cg) + sizeof(int32_t) + \ 448 /* old btotoff */ (fs)->fs_old_cpg * sizeof(int32_t) + \ 449 /* old boff */ (fs)->fs_old_cpg * sizeof(u_int16_t) + \ 450 /* inode map */ howmany((ipg), NBBY) + \ 451 /* block map */ howmany((fpg), NBBY) +\ 452 /* if present */ ((fs)->fs_contigsumsize <= 0 ? 0 : \ 453 /* cluster sum */ (fs)->fs_contigsumsize * sizeof(int32_t) + \ 454 /* cluster map */ howmany(fragstoblks(fs, (fpg)), NBBY))) 455 456#define CGSIZE(fs) CGSIZE_IF((fs), (fs)->fs_ipg, (fs)->fs_fpg) 457 458/* 459 * The minimal number of cylinder groups that should be created. 460 */ 461#define MINCYLGRPS 4 462 463 464/* 465 * Convert cylinder group to base address of its global summary info. 466 */ 467#define fs_cs(fs, indx) fs_csp[indx] 468 469/* 470 * Cylinder group block for a file system. 471 */ 472#define CG_MAGIC 0x090255 473struct cg { 474 int32_t cg_firstfield; /* historic cyl groups linked list */ 475 int32_t cg_magic; /* magic number */ 476 int32_t cg_old_time; /* time last written */ 477 int32_t cg_cgx; /* we are the cgx'th cylinder group */ 478 int16_t cg_old_ncyl; /* number of cyl's this cg */ 479 int16_t cg_old_niblk; /* number of inode blocks this cg */ 480 int32_t cg_ndblk; /* number of data blocks this cg */ 481 struct csum cg_cs; /* cylinder summary information */ 482 int32_t cg_rotor; /* position of last used block */ 483 int32_t cg_frotor; /* position of last used frag */ 484 int32_t cg_irotor; /* position of last used inode */ 485 int32_t cg_frsum[MAXFRAG]; /* counts of available frags */ 486 int32_t cg_old_btotoff; /* (int32) block totals per cylinder */ 487 int32_t cg_old_boff; /* (u_int16) free block positions */ 488 int32_t cg_iusedoff; /* (u_int8) used inode map */ 489 int32_t cg_freeoff; /* (u_int8) free block map */ 490 int32_t cg_nextfreeoff; /* (u_int8) next available space */ 491 int32_t cg_clustersumoff; /* (u_int32) counts of avail clusters */ 492 int32_t cg_clusteroff; /* (u_int8) free cluster map */ 493 int32_t cg_nclusterblks; /* number of clusters this cg */ 494 int32_t cg_niblk; /* number of inode blocks this cg */ 495 int32_t cg_initediblk; /* last initialized inode */ 496 int32_t cg_sparecon32[3]; /* reserved for future use */ 497 int64_t cg_time; /* time last written */ 498 int64_t cg_sparecon64[3]; /* reserved for future use */ 499 u_int8_t cg_space[1]; /* space for cylinder group maps */ 500/* actually longer */ 501}; 502 503/* 504 * The following structure is defined 505 * for compatibility with old file systems. 506 */ 507struct ocg { 508 int32_t cg_firstfield; /* historic linked list of cyl groups */ 509 int32_t cg_unused_1; /* used for incore cyl groups */ 510 int32_t cg_time; /* time last written */ 511 int32_t cg_cgx; /* we are the cgx'th cylinder group */ 512 int16_t cg_ncyl; /* number of cyl's this cg */ 513 int16_t cg_niblk; /* number of inode blocks this cg */ 514 int32_t cg_ndblk; /* number of data blocks this cg */ 515 struct csum cg_cs; /* cylinder summary information */ 516 int32_t cg_rotor; /* position of last used block */ 517 int32_t cg_frotor; /* position of last used frag */ 518 int32_t cg_irotor; /* position of last used inode */ 519 int32_t cg_frsum[8]; /* counts of available frags */ 520 int32_t cg_btot[32]; /* block totals per cylinder */ 521 int16_t cg_b[32][8]; /* positions of free blocks */ 522 u_int8_t cg_iused[256]; /* used inode map */ 523 int32_t cg_magic; /* magic number */ 524 u_int8_t cg_free[1]; /* free block map */ 525/* actually longer */ 526}; 527 528 529/* 530 * Macros for access to cylinder group array structures. 531 */ 532#define old_cg_blktot_old(cgp, ns) \ 533 (((struct ocg *)(cgp))->cg_btot) 534#define old_cg_blks_old(fs, cgp, cylno, ns) \ 535 (((struct ocg *)(cgp))->cg_b[cylno]) 536 537#define old_cg_blktot_new(cgp, ns) \ 538 ((int32_t *)((u_int8_t *)(cgp) + \ 539 ufs_rw32((cgp)->cg_old_btotoff, (ns)))) 540#define old_cg_blks_new(fs, cgp, cylno, ns) \ 541 ((int16_t *)((u_int8_t *)(cgp) + \ 542 ufs_rw32((cgp)->cg_old_boff, (ns))) + (cylno) * (fs)->fs_old_nrpos) 543 544#define old_cg_blktot(cgp, ns) \ 545 ((ufs_rw32((cgp)->cg_magic, (ns)) != CG_MAGIC) ? \ 546 old_cg_blktot_old(cgp, ns) : old_cg_blktot_new(cgp, ns)) 547#define old_cg_blks(fs, cgp, cylno, ns) \ 548 ((ufs_rw32((cgp)->cg_magic, (ns)) != CG_MAGIC) ? \ 549 old_cg_blks_old(fs, cgp, cylno, ns) : old_cg_blks_new(fs, cgp, cylno, ns)) 550 551#define cg_inosused_new(cgp, ns) \ 552 ((u_int8_t *)((u_int8_t *)(cgp) + \ 553 ufs_rw32((cgp)->cg_iusedoff, (ns)))) 554#define cg_blksfree_new(cgp, ns) \ 555 ((u_int8_t *)((u_int8_t *)(cgp) + \ 556 ufs_rw32((cgp)->cg_freeoff, (ns)))) 557#define cg_chkmagic_new(cgp, ns) \ 558 (ufs_rw32((cgp)->cg_magic, (ns)) == CG_MAGIC) 559 560#define cg_inosused_old(cgp, ns) \ 561 (((struct ocg *)(cgp))->cg_iused) 562#define cg_blksfree_old(cgp, ns) \ 563 (((struct ocg *)(cgp))->cg_free) 564#define cg_chkmagic_old(cgp, ns) \ 565 (ufs_rw32(((struct ocg *)(cgp))->cg_magic, (ns)) == CG_MAGIC) 566 567#define cg_inosused(cgp, ns) \ 568 ((ufs_rw32((cgp)->cg_magic, (ns)) != CG_MAGIC) ? \ 569 cg_inosused_old(cgp, ns) : cg_inosused_new(cgp, ns)) 570#define cg_blksfree(cgp, ns) \ 571 ((ufs_rw32((cgp)->cg_magic, (ns)) != CG_MAGIC) ? \ 572 cg_blksfree_old(cgp, ns) : cg_blksfree_new(cgp, ns)) 573#define cg_chkmagic(cgp, ns) \ 574 (cg_chkmagic_new(cgp, ns) || cg_chkmagic_old(cgp, ns)) 575 576#define cg_clustersfree(cgp, ns) \ 577 ((u_int8_t *)((u_int8_t *)(cgp) + \ 578 ufs_rw32((cgp)->cg_clusteroff, (ns)))) 579#define cg_clustersum(cgp, ns) \ 580 ((int32_t *)((u_int8_t *)(cgp) + \ 581 ufs_rw32((cgp)->cg_clustersumoff, (ns)))) 582 583 584/* 585 * Turn file system block numbers into disk block addresses. 586 * This maps file system blocks to device size blocks. 587 */ 588#define fsbtodb(fs, b) ((b) << (fs)->fs_fsbtodb) 589#define dbtofsb(fs, b) ((b) >> (fs)->fs_fsbtodb) 590 591/* 592 * Cylinder group macros to locate things in cylinder groups. 593 * They calc file system addresses of cylinder group data structures. 594 */ 595#define cgbase(fs, c) (((daddr_t)(fs)->fs_fpg) * (c)) 596#define cgstart_ufs1(fs, c) \ 597 (cgbase(fs, c) + (fs)->fs_old_cgoffset * ((c) & ~((fs)->fs_old_cgmask))) 598#define cgstart_ufs2(fs, c) cgbase((fs), (c)) 599#define cgstart(fs, c) ((fs)->fs_magic == FS_UFS2_MAGIC \ 600 ? cgstart_ufs2((fs), (c)) : cgstart_ufs1((fs), (c))) 601#define cgdmin(fs, c) (cgstart(fs, c) + (fs)->fs_dblkno) /* 1st data */ 602#define cgimin(fs, c) (cgstart(fs, c) + (fs)->fs_iblkno) /* inode blk */ 603#define cgsblock(fs, c) (cgstart(fs, c) + (fs)->fs_sblkno) /* super blk */ 604#define cgtod(fs, c) (cgstart(fs, c) + (fs)->fs_cblkno) /* cg block */ 605 606/* 607 * Macros for handling inode numbers: 608 * inode number to file system block offset. 609 * inode number to cylinder group number. 610 * inode number to file system block address. 611 */ 612#define ino_to_cg(fs, x) ((x) / (fs)->fs_ipg) 613#define ino_to_fsba(fs, x) \ 614 ((daddr_t)(cgimin(fs, ino_to_cg(fs, x)) + \ 615 (blkstofrags((fs), (((x) % (fs)->fs_ipg) / INOPB(fs)))))) 616#define ino_to_fsbo(fs, x) ((x) % INOPB(fs)) 617 618/* 619 * Give cylinder group number for a file system block. 620 * Give cylinder group block number for a file system block. 621 */ 622#define dtog(fs, d) ((d) / (fs)->fs_fpg) 623#define dtogd(fs, d) ((d) % (fs)->fs_fpg) 624 625/* 626 * Extract the bits for a block from a map. 627 * Compute the cylinder and rotational position of a cyl block addr. 628 */ 629#define blkmap(fs, map, loc) \ 630 (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag))) 631#define old_cbtocylno(fs, bno) \ 632 (fsbtodb(fs, bno) / (fs)->fs_old_spc) 633#define old_cbtorpos(fs, bno) \ 634 ((fs)->fs_old_nrpos <= 1 ? 0 : \ 635 (fsbtodb(fs, bno) % (fs)->fs_old_spc / (fs)->fs_old_nsect * (fs)->fs_old_trackskew + \ 636 fsbtodb(fs, bno) % (fs)->fs_old_spc % (fs)->fs_old_nsect * (fs)->fs_old_interleave) % \ 637 (fs)->fs_old_nsect * (fs)->fs_old_nrpos / (fs)->fs_old_npsect) 638 639/* 640 * The following macros optimize certain frequently calculated 641 * quantities by using shifts and masks in place of divisions 642 * modulos and multiplications. 643 */ 644#define blkoff(fs, loc) /* calculates (loc % fs->fs_bsize) */ \ 645 ((loc) & (fs)->fs_qbmask) 646#define fragoff(fs, loc) /* calculates (loc % fs->fs_fsize) */ \ 647 ((loc) & (fs)->fs_qfmask) 648#define lfragtosize(fs, frag) /* calculates ((off_t)frag * fs->fs_fsize) */ \ 649 (((off_t)(frag)) << (fs)->fs_fshift) 650#define lblktosize(fs, blk) /* calculates ((off_t)blk * fs->fs_bsize) */ \ 651 (((off_t)(blk)) << (fs)->fs_bshift) 652#define lblkno(fs, loc) /* calculates (loc / fs->fs_bsize) */ \ 653 ((loc) >> (fs)->fs_bshift) 654#define numfrags(fs, loc) /* calculates (loc / fs->fs_fsize) */ \ 655 ((loc) >> (fs)->fs_fshift) 656#define blkroundup(fs, size) /* calculates roundup(size, fs->fs_bsize) */ \ 657 (((size) + (fs)->fs_qbmask) & (fs)->fs_bmask) 658#define fragroundup(fs, size) /* calculates roundup(size, fs->fs_fsize) */ \ 659 (((size) + (fs)->fs_qfmask) & (fs)->fs_fmask) 660#define fragstoblks(fs, frags) /* calculates (frags / fs->fs_frag) */ \ 661 ((frags) >> (fs)->fs_fragshift) 662#define blkstofrags(fs, blks) /* calculates (blks * fs->fs_frag) */ \ 663 ((blks) << (fs)->fs_fragshift) 664#define fragnum(fs, fsb) /* calculates (fsb % fs->fs_frag) */ \ 665 ((fsb) & ((fs)->fs_frag - 1)) 666#define blknum(fs, fsb) /* calculates rounddown(fsb, fs->fs_frag) */ \ 667 ((fsb) &~ ((fs)->fs_frag - 1)) 668 669/* 670 * Determine the number of available frags given a 671 * percentage to hold in reserve. 672 */ 673#define freespace(fs, percentreserved) \ 674 (blkstofrags((fs), (fs)->fs_cstotal.cs_nbfree) + \ 675 (fs)->fs_cstotal.cs_nffree - \ 676 (((off_t)((fs)->fs_dsize)) * (percentreserved) / 100)) 677 678/* 679 * Determining the size of a file block in the file system. 680 */ 681#define blksize(fs, ip, lbn) \ 682 (((lbn) >= NDADDR || (ip)->i_size >= lblktosize(fs, (lbn) + 1)) \ 683 ? (fs)->fs_bsize \ 684 : (fragroundup(fs, blkoff(fs, (ip)->i_size)))) 685 686#define sblksize(fs, size, lbn) \ 687 (((lbn) >= NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \ 688 ? (fs)->fs_bsize \ 689 : (fragroundup(fs, blkoff(fs, (size))))) 690 691 692/* 693 * Number of inodes in a secondary storage block/fragment. 694 */ 695#define INOPB(fs) ((fs)->fs_inopb) 696#define INOPF(fs) ((fs)->fs_inopb >> (fs)->fs_fragshift) 697 698/* 699 * Number of indirects in a file system block. 700 */ 701#define NINDIR(fs) ((fs)->fs_nindir) 702 703/* 704 * Apple UFS Label: 705 * We check for this to decide to use APPLEUFS_DIRBLKSIZ 706 */ 707#define APPLEUFS_LABEL_MAGIC 0x4c41424c /* LABL */ 708#define APPLEUFS_LABEL_SIZE 1024 709#define APPLEUFS_LABEL_OFFSET (BBSIZE - APPLEUFS_LABEL_SIZE) /* located at 7k */ 710#define APPLEUFS_LABEL_VERSION 1 711#define APPLEUFS_MAX_LABEL_NAME 512 712 713struct appleufslabel { 714 u_int32_t ul_magic; 715 u_int16_t ul_checksum; 716 u_int16_t ul_unused0; 717 u_int32_t ul_version; 718 u_int32_t ul_time; 719 u_int16_t ul_namelen; 720 u_char ul_name[APPLEUFS_MAX_LABEL_NAME]; /* Warning: may not be null terminated */ 721 u_int16_t ul_unused1; 722 u_int64_t ul_uuid; /* Note this is only 4 byte aligned */ 723 u_char ul_reserved[24]; 724 u_char ul_unused[460]; 725} __attribute__((__packed__)); 726 727 728#endif /* !_UFS_FFS_FS_H_ */ 729