fs.h revision 111238
1/* 2 * Copyright (c) 1982, 1986, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)fs.h 8.13 (Berkeley) 3/21/95 34 * $FreeBSD: head/sys/ufs/ffs/fs.h 111238 2003-02-22 00:19:26Z mckusick $ 35 */ 36 37#ifndef _UFS_FFS_FS_H_ 38#define _UFS_FFS_FS_H_ 39 40/* 41 * Each disk drive contains some number of filesystems. 42 * A filesystem consists of a number of cylinder groups. 43 * Each cylinder group has inodes and data. 44 * 45 * A filesystem is described by its super-block, which in turn 46 * describes the cylinder groups. The super-block is critical 47 * data and is replicated in each cylinder group to protect against 48 * catastrophic loss. This is done at `newfs' time and the critical 49 * super-block data does not change, so the copies need not be 50 * referenced further unless disaster strikes. 51 * 52 * For filesystem fs, the offsets of the various blocks of interest 53 * are given in the super block as: 54 * [fs->fs_sblkno] Super-block 55 * [fs->fs_cblkno] Cylinder group block 56 * [fs->fs_iblkno] Inode blocks 57 * [fs->fs_dblkno] Data blocks 58 * The beginning of cylinder group cg in fs, is given by 59 * the ``cgbase(fs, cg)'' macro. 60 * 61 * Depending on the architecture and the media, the superblock may 62 * reside in any one of four places. For tiny media where every block 63 * counts, it is placed at the very front of the partition. Historically, 64 * UFS1 placed it 8K from the front to leave room for the disk label and 65 * a small bootstrap. For UFS2 it got moved to 64K from the front to leave 66 * room for the disk label and a bigger bootstrap, and for really piggy 67 * systems we check at 256K from the front if the first three fail. In 68 * all cases the size of the superblock will be SBLOCKSIZE. All values are 69 * given in byte-offset form, so they do not imply a sector size. The 70 * SBLOCKSEARCH specifies the order in which the locations should be searched. 71 */ 72#define SBLOCK_FLOPPY 0 73#define SBLOCK_UFS1 8192 74#define SBLOCK_UFS2 65536 75#define SBLOCK_PIGGY 262144 76#define SBLOCKSIZE 8192 77#define SBLOCKSEARCH \ 78 { SBLOCK_UFS2, SBLOCK_UFS1, SBLOCK_FLOPPY, SBLOCK_PIGGY, -1 } 79 80/* 81 * Max number of fragments per block. This value is NOT tweakable. 82 */ 83#define MAXFRAG 8 84 85/* 86 * Addresses stored in inodes are capable of addressing fragments 87 * of `blocks'. File system blocks of at most size MAXBSIZE can 88 * be optionally broken into 2, 4, or 8 pieces, each of which is 89 * addressable; these pieces may be DEV_BSIZE, or some multiple of 90 * a DEV_BSIZE unit. 91 * 92 * Large files consist of exclusively large data blocks. To avoid 93 * undue wasted disk space, the last data block of a small file may be 94 * allocated as only as many fragments of a large block as are 95 * necessary. The filesystem format retains only a single pointer 96 * to such a fragment, which is a piece of a single large block that 97 * has been divided. The size of such a fragment is determinable from 98 * information in the inode, using the ``blksize(fs, ip, lbn)'' macro. 99 * 100 * The filesystem records space availability at the fragment level; 101 * to determine block availability, aligned fragments are examined. 102 */ 103 104/* 105 * MINBSIZE is the smallest allowable block size. 106 * In order to insure that it is possible to create files of size 107 * 2^32 with only two levels of indirection, MINBSIZE is set to 4096. 108 * MINBSIZE must be big enough to hold a cylinder group block, 109 * thus changes to (struct cg) must keep its size within MINBSIZE. 110 * Note that super blocks are always of size SBSIZE, 111 * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE. 112 */ 113#define MINBSIZE 4096 114 115/* 116 * The path name on which the filesystem is mounted is maintained 117 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in 118 * the super block for this name. 119 */ 120#define MAXMNTLEN 468 121 122/* 123 * The volume name for this filesystem is maintained in fs_volname. 124 * MAXVOLLEN defines the length of the buffer allocated. 125 */ 126#define MAXVOLLEN 32 127 128/* 129 * There is a 128-byte region in the superblock reserved for in-core 130 * pointers to summary information. Originally this included an array 131 * of pointers to blocks of struct csum; now there are just a few 132 * pointers and the remaining space is padded with fs_ocsp[]. 133 * 134 * NOCSPTRS determines the size of this padding. One pointer (fs_csp) 135 * is taken away to point to a contiguous array of struct csum for 136 * all cylinder groups; a second (fs_maxcluster) points to an array 137 * of cluster sizes that is computed as cylinder groups are inspected, 138 * and the third points to an array that tracks the creation of new 139 * directories. A fourth pointer, fs_active, is used when creating 140 * snapshots; it points to a bitmap of cylinder groups for which the 141 * free-block bitmap has changed since the snapshot operation began. 142 */ 143#define NOCSPTRS ((128 / sizeof(void *)) - 4) 144 145/* 146 * A summary of contiguous blocks of various sizes is maintained 147 * in each cylinder group. Normally this is set by the initial 148 * value of fs_maxcontig. To conserve space, a maximum summary size 149 * is set by FS_MAXCONTIG. 150 */ 151#define FS_MAXCONTIG 16 152 153/* 154 * MINFREE gives the minimum acceptable percentage of filesystem 155 * blocks which may be free. If the freelist drops below this level 156 * only the superuser may continue to allocate blocks. This may 157 * be set to 0 if no reserve of free blocks is deemed necessary, 158 * however throughput drops by fifty percent if the filesystem 159 * is run at between 95% and 100% full; thus the minimum default 160 * value of fs_minfree is 5%. However, to get good clustering 161 * performance, 10% is a better choice. hence we use 10% as our 162 * default value. With 10% free space, fragmentation is not a 163 * problem, so we choose to optimize for time. 164 */ 165#define MINFREE 8 166#define DEFAULTOPT FS_OPTTIME 167 168/* 169 * Grigoriy Orlov <gluk@ptci.ru> has done some extensive work to fine 170 * tune the layout preferences for directories within a filesystem. 171 * His algorithm can be tuned by adjusting the following parameters 172 * which tell the system the average file size and the average number 173 * of files per directory. These defaults are well selected for typical 174 * filesystems, but may need to be tuned for odd cases like filesystems 175 * being used for sqiud caches or news spools. 176 */ 177#define AVFILESIZ 16384 /* expected average file size */ 178#define AFPDIR 64 /* expected number of files per directory */ 179 180/* 181 * The maximum number of snapshot nodes that can be associated 182 * with each filesystem. This limit affects only the number of 183 * snapshot files that can be recorded within the superblock so 184 * that they can be found when the filesystem is mounted. However, 185 * maintaining too many will slow the filesystem performance, so 186 * having this limit is a good idea. 187 */ 188#define FSMAXSNAP 20 189 190/* 191 * Used to identify special blocks in snapshots: 192 * 193 * BLK_NOCOPY - A block that was unallocated at the time the snapshot 194 * was taken, hence does not need to be copied when written. 195 * BLK_SNAP - A block held by another snapshot that is not needed by this 196 * snapshot. When the other snapshot is freed, the BLK_SNAP entries 197 * are converted to BLK_NOCOPY. These are needed to allow fsck to 198 * identify blocks that are in use by other snapshots (which are 199 * expunged from this snapshot). 200 */ 201#define BLK_NOCOPY ((ufs2_daddr_t)(1)) 202#define BLK_SNAP ((ufs2_daddr_t)(2)) 203 204/* 205 * Sysctl values for the fast filesystem. 206 */ 207#define FFS_ADJ_REFCNT 1 /* adjust inode reference count */ 208#define FFS_ADJ_BLKCNT 2 /* adjust inode used block count */ 209#define FFS_BLK_FREE 3 /* free range of blocks in map */ 210#define FFS_DIR_FREE 4 /* free specified dir inodes in map */ 211#define FFS_FILE_FREE 5 /* free specified file inodes in map */ 212#define FFS_SET_FLAGS 6 /* set filesystem flags */ 213#define FFS_MAXID 7 /* number of valid ffs ids */ 214 215/* 216 * Command structure passed in to the filesystem to adjust filesystem values. 217 */ 218#define FFS_CMD_VERSION 0x19790518 /* version ID */ 219struct fsck_cmd { 220 int32_t version; /* version of command structure */ 221 int32_t handle; /* reference to filesystem to be changed */ 222 int64_t value; /* inode or block number to be affected */ 223 int64_t size; /* amount or range to be adjusted */ 224 int64_t spare; /* reserved for future use */ 225}; 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}; 239struct csum_total { 240 int64_t cs_ndir; /* number of directories */ 241 int64_t cs_nbfree; /* number of free blocks */ 242 int64_t cs_nifree; /* number of free inodes */ 243 int64_t cs_nffree; /* number of free frags */ 244 int64_t cs_numclusters; /* number of free clusters */ 245 int64_t cs_spare[3]; /* future expansion */ 246}; 247 248/* 249 * Super block for an FFS filesystem. 250 */ 251struct fs { 252 int32_t fs_firstfield; /* historic filesystem linked list, */ 253 int32_t fs_unused_1; /* used for incore super blocks */ 254 int32_t fs_sblkno; /* offset of super-block in filesys */ 255 int32_t fs_cblkno; /* offset of cyl-block in filesys */ 256 int32_t fs_iblkno; /* offset of inode-blocks in filesys */ 257 int32_t fs_dblkno; /* offset of first data after cg */ 258 int32_t fs_old_cgoffset; /* cylinder group offset in cylinder */ 259 int32_t fs_old_cgmask; /* used to calc mod fs_ntrak */ 260 int32_t fs_old_time; /* last time written */ 261 int32_t fs_old_size; /* number of blocks in fs */ 262 int32_t fs_old_dsize; /* number of data blocks in fs */ 263 int32_t fs_ncg; /* number of cylinder groups */ 264 int32_t fs_bsize; /* size of basic blocks in fs */ 265 int32_t fs_fsize; /* size of frag blocks in fs */ 266 int32_t fs_frag; /* number of frags in a block in fs */ 267/* these are configuration parameters */ 268 int32_t fs_minfree; /* minimum percentage of free blocks */ 269 int32_t fs_old_rotdelay; /* num of ms for optimal next block */ 270 int32_t fs_old_rps; /* disk revolutions per second */ 271/* these fields can be computed from the others */ 272 int32_t fs_bmask; /* ``blkoff'' calc of blk offsets */ 273 int32_t fs_fmask; /* ``fragoff'' calc of frag offsets */ 274 int32_t fs_bshift; /* ``lblkno'' calc of logical blkno */ 275 int32_t fs_fshift; /* ``numfrags'' calc number of frags */ 276/* these are configuration parameters */ 277 int32_t fs_maxcontig; /* max number of contiguous blks */ 278 int32_t fs_maxbpg; /* max number of blks per cyl group */ 279/* these fields can be computed from the others */ 280 int32_t fs_fragshift; /* block to frag shift */ 281 int32_t fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */ 282 int32_t fs_sbsize; /* actual size of super block */ 283 int32_t fs_spare1[2]; /* old fs_csmask */ 284 /* old fs_csshift */ 285 int32_t fs_nindir; /* value of NINDIR */ 286 int32_t fs_inopb; /* value of INOPB */ 287 int32_t fs_old_nspf; /* value of NSPF */ 288/* yet another configuration parameter */ 289 int32_t fs_optim; /* optimization preference, see below */ 290 int32_t fs_old_npsect; /* # sectors/track including spares */ 291 int32_t fs_old_interleave; /* hardware sector interleave */ 292 int32_t fs_old_trackskew; /* sector 0 skew, per track */ 293 int32_t fs_id[2]; /* unique filesystem id */ 294/* sizes determined by number of cylinder groups and their sizes */ 295 int32_t fs_old_csaddr; /* blk addr of cyl grp summary area */ 296 int32_t fs_cssize; /* size of cyl grp summary area */ 297 int32_t fs_cgsize; /* cylinder group size */ 298 int32_t fs_spare2; /* old fs_ntrak */ 299 int32_t fs_old_nsect; /* sectors per track */ 300 int32_t fs_old_spc; /* sectors per cylinder */ 301 int32_t fs_old_ncyl; /* cylinders in filesystem */ 302 int32_t fs_old_cpg; /* cylinders per group */ 303 int32_t fs_ipg; /* inodes per group */ 304 int32_t fs_fpg; /* blocks per group * fs_frag */ 305/* this data must be re-computed after crashes */ 306 struct csum fs_old_cstotal; /* cylinder summary information */ 307/* these fields are cleared at mount time */ 308 int8_t fs_fmod; /* super block modified flag */ 309 int8_t fs_clean; /* filesystem is clean flag */ 310 int8_t fs_ronly; /* mounted read-only flag */ 311 int8_t fs_old_flags; /* old FS_ flags */ 312 u_char fs_fsmnt[MAXMNTLEN]; /* name mounted on */ 313 u_char fs_volname[MAXVOLLEN]; /* volume name */ 314 u_int64_t fs_swuid; /* system-wide uid */ 315 int32_t fs_pad; /* due to alignment of fs_swuid */ 316/* these fields retain the current block allocation info */ 317 int32_t fs_cgrotor; /* last cg searched */ 318 void *fs_ocsp[NOCSPTRS]; /* padding; was list of fs_cs buffers */ 319 u_int8_t *fs_contigdirs; /* # of contiguously allocated dirs */ 320 struct csum *fs_csp; /* cg summary info buffer for fs_cs */ 321 int32_t *fs_maxcluster; /* max cluster in each cyl group */ 322 u_int *fs_active; /* used by snapshots to track fs */ 323 int32_t fs_old_cpc; /* cyl per cycle in postbl */ 324 int32_t fs_maxbsize; /* maximum blocking factor permitted */ 325 int64_t fs_sparecon64[17]; /* old rotation block list head */ 326 int64_t fs_sblockloc; /* byte offset of standard superblock */ 327 struct csum_total fs_cstotal; /* cylinder summary information */ 328 ufs_time_t fs_time; /* last time written */ 329 int64_t fs_size; /* number of blocks in fs */ 330 int64_t fs_dsize; /* number of data blocks in fs */ 331 ufs2_daddr_t fs_csaddr; /* blk addr of cyl grp summary area */ 332 int64_t fs_pendingblocks; /* blocks in process of being freed */ 333 int32_t fs_pendinginodes; /* inodes in process of being freed */ 334 int32_t fs_snapinum[FSMAXSNAP];/* list of snapshot inode numbers */ 335 int32_t fs_avgfilesize; /* expected average file size */ 336 int32_t fs_avgfpdir; /* expected # of files per directory */ 337 int32_t fs_save_cgsize; /* save real cg size to use fs_bsize */ 338 int32_t fs_sparecon32[26]; /* reserved for future constants */ 339 int32_t fs_flags; /* see FS_ flags below */ 340 int32_t fs_contigsumsize; /* size of cluster summary array */ 341 int32_t fs_maxsymlinklen; /* max length of an internal symlink */ 342 int32_t fs_old_inodefmt; /* format of on-disk inodes */ 343 u_int64_t fs_maxfilesize; /* maximum representable file size */ 344 int64_t fs_qbmask; /* ~fs_bmask for use with 64-bit size */ 345 int64_t fs_qfmask; /* ~fs_fmask for use with 64-bit size */ 346 int32_t fs_state; /* validate fs_clean field */ 347 int32_t fs_old_postblformat; /* format of positional layout tables */ 348 int32_t fs_old_nrpos; /* number of rotational positions */ 349 int32_t fs_spare5[2]; /* old fs_postbloff */ 350 /* old fs_rotbloff */ 351 int32_t fs_magic; /* magic number */ 352}; 353 354/* Sanity checking. */ 355#ifdef CTASSERT 356CTASSERT(sizeof(struct fs) == 1376); 357#endif 358 359/* 360 * Filesystem identification 361 */ 362#define FS_UFS1_MAGIC 0x011954 /* UFS1 fast filesystem magic number */ 363#define FS_UFS2_MAGIC 0x19540119 /* UFS2 fast filesystem magic number */ 364#define FS_OKAY 0x7c269d38 /* superblock checksum */ 365#define FS_42INODEFMT -1 /* 4.2BSD inode format */ 366#define FS_44INODEFMT 2 /* 4.4BSD inode format */ 367 368/* 369 * Preference for optimization. 370 */ 371#define FS_OPTTIME 0 /* minimize allocation time */ 372#define FS_OPTSPACE 1 /* minimize disk fragmentation */ 373 374/* 375 * Filesystem flags. 376 * 377 * The FS_UNCLEAN flag is set by the kernel when the filesystem was 378 * mounted with fs_clean set to zero. The FS_DOSOFTDEP flag indicates 379 * that the filesystem should be managed by the soft updates code. 380 * Note that the FS_NEEDSFSCK flag is set and cleared only by the 381 * fsck utility. It is set when background fsck finds an unexpected 382 * inconsistency which requires a traditional foreground fsck to be 383 * run. Such inconsistencies should only be found after an uncorrectable 384 * disk error. A foreground fsck will clear the FS_NEEDSFSCK flag when 385 * it has successfully cleaned up the filesystem. The kernel uses this 386 * flag to enforce that inconsistent filesystems be mounted read-only. 387 * The FS_INDEXDIRS flag when set indicates that the kernel maintains 388 * on-disk auxiliary indexes (such as B-trees) for speeding directory 389 * accesses. Kernels that do not support auxiliary indicies clear the 390 * flag to indicate that the indicies need to be rebuilt (by fsck) before 391 * they can be used. 392 * 393 * FS_ACLS indicates that ACLs are administratively enabled for the 394 * file system, so they should be loaded from extended attributes, 395 * observed for access control purposes, and be administered by object 396 * owners. FS_MULTILABEL indicates that the TrustedBSD MAC Framework 397 * should attempt to back MAC labels into extended attributes on the 398 * file system rather than maintain a single mount label for all 399 * objects. 400 */ 401#define FS_UNCLEAN 0x01 /* filesystem not clean at mount */ 402#define FS_DOSOFTDEP 0x02 /* filesystem using soft dependencies */ 403#define FS_NEEDSFSCK 0x04 /* filesystem needs sync fsck before mount */ 404#define FS_INDEXDIRS 0x08 /* kernel supports indexed directories */ 405#define FS_ACLS 0x10 /* file system has ACLs enabled */ 406#define FS_MULTILABEL 0x20 /* file system is MAC multi-label */ 407#define FS_FLAGS_UPDATED 0x80 /* flags have been moved to new location */ 408 409/* 410 * Macros to access bits in the fs_active array. 411 */ 412#define ACTIVECGNUM(fs, cg) ((fs)->fs_active[(cg) / (NBBY * sizeof(int))]) 413#define ACTIVECGOFF(cg) (1 << ((cg) % (NBBY * sizeof(int)))) 414 415/* 416 * The size of a cylinder group is calculated by CGSIZE. The maximum size 417 * is limited by the fact that cylinder groups are at most one block. 418 * Its size is derived from the size of the maps maintained in the 419 * cylinder group and the (struct cg) size. 420 */ 421#define CGSIZE(fs) \ 422 /* base cg */ (sizeof(struct cg) + sizeof(int32_t) + \ 423 /* old btotoff */ (fs)->fs_old_cpg * sizeof(int32_t) + \ 424 /* old boff */ (fs)->fs_old_cpg * sizeof(u_int16_t) + \ 425 /* inode map */ howmany((fs)->fs_ipg, NBBY) + \ 426 /* block map */ howmany((fs)->fs_fpg, NBBY) +\ 427 /* if present */ ((fs)->fs_contigsumsize <= 0 ? 0 : \ 428 /* cluster sum */ (fs)->fs_contigsumsize * sizeof(int32_t) + \ 429 /* cluster map */ howmany(fragstoblks(fs, (fs)->fs_fpg), NBBY))) 430 431/* 432 * The minimal number of cylinder groups that should be created. 433 */ 434#define MINCYLGRPS 4 435 436/* 437 * Convert cylinder group to base address of its global summary info. 438 */ 439#define fs_cs(fs, indx) fs_csp[indx] 440 441/* 442 * Cylinder group block for a filesystem. 443 */ 444#define CG_MAGIC 0x090255 445struct cg { 446 int32_t cg_firstfield; /* historic cyl groups linked list */ 447 int32_t cg_magic; /* magic number */ 448 int32_t cg_old_time; /* time last written */ 449 int32_t cg_cgx; /* we are the cgx'th cylinder group */ 450 int16_t cg_old_ncyl; /* number of cyl's this cg */ 451 int16_t cg_old_niblk; /* number of inode blocks this cg */ 452 int32_t cg_ndblk; /* number of data blocks this cg */ 453 struct csum cg_cs; /* cylinder summary information */ 454 int32_t cg_rotor; /* position of last used block */ 455 int32_t cg_frotor; /* position of last used frag */ 456 int32_t cg_irotor; /* position of last used inode */ 457 int32_t cg_frsum[MAXFRAG]; /* counts of available frags */ 458 int32_t cg_old_btotoff; /* (int32) block totals per cylinder */ 459 int32_t cg_old_boff; /* (u_int16) free block positions */ 460 int32_t cg_iusedoff; /* (u_int8) used inode map */ 461 int32_t cg_freeoff; /* (u_int8) free block map */ 462 int32_t cg_nextfreeoff; /* (u_int8) next available space */ 463 int32_t cg_clustersumoff; /* (u_int32) counts of avail clusters */ 464 int32_t cg_clusteroff; /* (u_int8) free cluster map */ 465 int32_t cg_nclusterblks; /* number of clusters this cg */ 466 int32_t cg_niblk; /* number of inode blocks this cg */ 467 int32_t cg_initediblk; /* last initialized inode */ 468 int32_t cg_sparecon32[3]; /* reserved for future use */ 469 ufs_time_t cg_time; /* time last written */ 470 int64_t cg_sparecon64[3]; /* reserved for future use */ 471 u_int8_t cg_space[1]; /* space for cylinder group maps */ 472/* actually longer */ 473}; 474 475/* 476 * Macros for access to cylinder group array structures 477 */ 478#define cg_chkmagic(cgp) ((cgp)->cg_magic == CG_MAGIC) 479#define cg_inosused(cgp) \ 480 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_iusedoff)) 481#define cg_blksfree(cgp) \ 482 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_freeoff)) 483#define cg_clustersfree(cgp) \ 484 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_clusteroff)) 485#define cg_clustersum(cgp) \ 486 ((int32_t *)((u_int8_t *)(cgp) + (cgp)->cg_clustersumoff)) 487 488/* 489 * Turn filesystem block numbers into disk block addresses. 490 * This maps filesystem blocks to device size blocks. 491 */ 492#define fsbtodb(fs, b) ((b) << (fs)->fs_fsbtodb) 493#define dbtofsb(fs, b) ((b) >> (fs)->fs_fsbtodb) 494 495/* 496 * Cylinder group macros to locate things in cylinder groups. 497 * They calc filesystem addresses of cylinder group data structures. 498 */ 499#define cgbase(fs, c) (((ufs2_daddr_t)(fs)->fs_fpg) * (c)) 500#define cgdmin(fs, c) (cgstart(fs, c) + (fs)->fs_dblkno) /* 1st data */ 501#define cgimin(fs, c) (cgstart(fs, c) + (fs)->fs_iblkno) /* inode blk */ 502#define cgsblock(fs, c) (cgstart(fs, c) + (fs)->fs_sblkno) /* super blk */ 503#define cgtod(fs, c) (cgstart(fs, c) + (fs)->fs_cblkno) /* cg block */ 504#define cgstart(fs, c) \ 505 ((fs)->fs_magic == FS_UFS2_MAGIC ? cgbase(fs, c) : \ 506 (cgbase(fs, c) + (fs)->fs_old_cgoffset * ((c) & ~((fs)->fs_old_cgmask)))) 507 508/* 509 * Macros for handling inode numbers: 510 * inode number to filesystem block offset. 511 * inode number to cylinder group number. 512 * inode number to filesystem block address. 513 */ 514#define ino_to_cg(fs, x) ((x) / (fs)->fs_ipg) 515#define ino_to_fsba(fs, x) \ 516 ((ufs2_daddr_t)(cgimin(fs, ino_to_cg(fs, x)) + \ 517 (blkstofrags((fs), (((x) % (fs)->fs_ipg) / INOPB(fs)))))) 518#define ino_to_fsbo(fs, x) ((x) % INOPB(fs)) 519 520/* 521 * Give cylinder group number for a filesystem block. 522 * Give cylinder group block number for a filesystem block. 523 */ 524#define dtog(fs, d) ((d) / (fs)->fs_fpg) 525#define dtogd(fs, d) ((d) % (fs)->fs_fpg) 526 527/* 528 * Extract the bits for a block from a map. 529 * Compute the cylinder and rotational position of a cyl block addr. 530 */ 531#define blkmap(fs, map, loc) \ 532 (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag))) 533 534/* 535 * The following macros optimize certain frequently calculated 536 * quantities by using shifts and masks in place of divisions 537 * modulos and multiplications. 538 */ 539#define blkoff(fs, loc) /* calculates (loc % fs->fs_bsize) */ \ 540 ((loc) & (fs)->fs_qbmask) 541#define fragoff(fs, loc) /* calculates (loc % fs->fs_fsize) */ \ 542 ((loc) & (fs)->fs_qfmask) 543#define lfragtosize(fs, frag) /* calculates ((off_t)frag * fs->fs_fsize) */ \ 544 (((off_t)(frag)) << (fs)->fs_fshift) 545#define lblktosize(fs, blk) /* calculates ((off_t)blk * fs->fs_bsize) */ \ 546 (((off_t)(blk)) << (fs)->fs_bshift) 547/* Use this only when `blk' is known to be small, e.g., < NDADDR. */ 548#define smalllblktosize(fs, blk) /* calculates (blk * fs->fs_bsize) */ \ 549 ((blk) << (fs)->fs_bshift) 550#define lblkno(fs, loc) /* calculates (loc / fs->fs_bsize) */ \ 551 ((loc) >> (fs)->fs_bshift) 552#define numfrags(fs, loc) /* calculates (loc / fs->fs_fsize) */ \ 553 ((loc) >> (fs)->fs_fshift) 554#define blkroundup(fs, size) /* calculates roundup(size, fs->fs_bsize) */ \ 555 (((size) + (fs)->fs_qbmask) & (fs)->fs_bmask) 556#define fragroundup(fs, size) /* calculates roundup(size, fs->fs_fsize) */ \ 557 (((size) + (fs)->fs_qfmask) & (fs)->fs_fmask) 558#define fragstoblks(fs, frags) /* calculates (frags / fs->fs_frag) */ \ 559 ((frags) >> (fs)->fs_fragshift) 560#define blkstofrags(fs, blks) /* calculates (blks * fs->fs_frag) */ \ 561 ((blks) << (fs)->fs_fragshift) 562#define fragnum(fs, fsb) /* calculates (fsb % fs->fs_frag) */ \ 563 ((fsb) & ((fs)->fs_frag - 1)) 564#define blknum(fs, fsb) /* calculates rounddown(fsb, fs->fs_frag) */ \ 565 ((fsb) &~ ((fs)->fs_frag - 1)) 566 567/* 568 * Determine the number of available frags given a 569 * percentage to hold in reserve. 570 */ 571#define freespace(fs, percentreserved) \ 572 (blkstofrags((fs), (fs)->fs_cstotal.cs_nbfree) + \ 573 (fs)->fs_cstotal.cs_nffree - \ 574 (((off_t)((fs)->fs_dsize)) * (percentreserved) / 100)) 575 576/* 577 * Determining the size of a file block in the filesystem. 578 */ 579#define blksize(fs, ip, lbn) \ 580 (((lbn) >= NDADDR || (ip)->i_size >= smalllblktosize(fs, (lbn) + 1)) \ 581 ? (fs)->fs_bsize \ 582 : (fragroundup(fs, blkoff(fs, (ip)->i_size)))) 583#define sblksize(fs, size, lbn) \ 584 (((lbn) >= NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \ 585 ? (fs)->fs_bsize \ 586 : (fragroundup(fs, blkoff(fs, (size))))) 587 588 589/* 590 * Number of inodes in a secondary storage block/fragment. 591 */ 592#define INOPB(fs) ((fs)->fs_inopb) 593#define INOPF(fs) ((fs)->fs_inopb >> (fs)->fs_fragshift) 594 595/* 596 * Number of indirects in a filesystem block. 597 */ 598#define NINDIR(fs) ((fs)->fs_nindir) 599 600extern int inside[], around[]; 601extern u_char *fragtbl[]; 602 603#endif 604