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. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)fs.h 8.13 (Berkeley) 3/21/95 30 * $FreeBSD: src/sys/ufs/ffs/fs.h,v 1.14.2.3 2001/09/21 19:15:22 dillon Exp $ 31 */ 32 33 #ifndef _VFS_UFS_FS_H_ 34 #define _VFS_UFS_FS_H_ 35 36 /* 37 * Each disk drive contains some number of filesystems. 38 * A filesystem consists of a number of cylinder groups. 39 * Each cylinder group has inodes and data. 40 * 41 * A filesystem is described by its super-block, which in turn 42 * describes the cylinder groups. The super-block is critical 43 * data and is replicated in each cylinder group to protect against 44 * catastrophic loss. This is done at `newfs' time and the critical 45 * super-block data does not change, so the copies need not be 46 * referenced further unless disaster strikes. 47 * 48 * For filesystem fs, the offsets of the various blocks of interest 49 * are given in the super block as: 50 * [fs->fs_sblkno] Super-block 51 * [fs->fs_cblkno] Cylinder group block 52 * [fs->fs_iblkno] Inode blocks 53 * [fs->fs_dblkno] Data blocks 54 * The beginning of cylinder group cg in fs, is given by 55 * the ``cgbase(fs, cg)'' macro. 56 * 57 * The first boot and super blocks are given in absolute disk addresses. 58 * The byte-offset forms are preferred, as they don't imply a sector size. 59 */ 60 #define BBSIZE 8192 61 #define SBSIZE 8192 62 #define BBOFF ((off_t)(0)) 63 #define SBOFF ((off_t)(BBOFF + BBSIZE)) 64 #define BBLOCK ((ufs_daddr_t)(0)) 65 66 /* 67 * Addresses stored in inodes are capable of addressing fragments 68 * of `blocks'. Filesystem blocks of at most size MAXBSIZE can 69 * be optionally broken into 2, 4, or 8 pieces, each of which is 70 * addressable; these pieces may be DEV_BSIZE, or some multiple of 71 * a DEV_BSIZE unit. 72 * 73 * Large files consist of exclusively large data blocks. To avoid 74 * undue wasted disk space, the last data block of a small file may be 75 * allocated as only as many fragments of a large block as are 76 * necessary. The filesystem format retains only a single pointer 77 * to such a fragment, which is a piece of a single large block that 78 * has been divided. The size of such a fragment is determinable from 79 * information in the inode, using the ``blksize(fs, ip, lbn)'' macro. 80 * 81 * The filesystem records space availability at the fragment level; 82 * to determine block availability, aligned fragments are examined. 83 */ 84 85 /* 86 * MINBSIZE is the smallest allowable block size. 87 * In order to insure that it is possible to create files of size 88 * 2^32 with only two levels of indirection, MINBSIZE is set to 4096. 89 * MINBSIZE must be big enough to hold a cylinder group block, 90 * thus changes to (struct cg) must keep its size within MINBSIZE. 91 * Note that super blocks are always of size SBSIZE, 92 * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE. 93 */ 94 #define MINBSIZE 4096 95 96 /* 97 * The path name on which the filesystem is mounted is maintained 98 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in 99 * the super block for this name. 100 */ 101 #define MAXMNTLEN 468 102 103 /* 104 * The volume name for this filesystem is maintained in fs_volname. 105 * MAXVOLLEN defines the length of the buffer allocated. 106 */ 107 #define MAXVOLLEN 32 108 109 /* 110 * There is a 128-byte region in the superblock reserved for in-core 111 * pointers to summary information. Originally this included an array 112 * of pointers to blocks of struct csum; now there are just three 113 * pointers and the remaining space is padded with fs_ocsp[]. 114 * 115 * NOCSPTRS determines the size of this padding. One pointer (fs_csp) 116 * is taken away to point to a contiguous array of struct csum for 117 * all cylinder groups; a second (fs_maxcluster) points to an array 118 * of cluster sizes that is computed as cylinder groups are inspected, 119 * and the third points to an array that tracks the creation of new 120 * directories. 121 */ 122 #define NOCSPTRS ((128 / sizeof(void *)) - 3) 123 124 /* 125 * A summary of contiguous blocks of various sizes is maintained 126 * in each cylinder group. Normally this is set by the initial 127 * value of fs_maxcontig. To conserve space, a maximum summary size 128 * is set by FS_MAXCONTIG. 129 */ 130 #define FS_MAXCONTIG 16 131 132 /* 133 * MINFREE gives the minimum acceptable percentage of filesystem 134 * blocks which may be free. If the freelist drops below this level 135 * only the superuser may continue to allocate blocks. This may 136 * be set to 0 if no reserve of free blocks is deemed necessary, 137 * however throughput drops by fifty percent if the filesystem 138 * is run at between 95% and 100% full; thus the minimum default 139 * value of fs_minfree is 5%. However, to get good clustering 140 * performance, 10% is a better choice. hence we use 10% as our 141 * default value. With 10% free space, fragmentation is not a 142 * problem, so we choose to optimize for time. 143 */ 144 #define MINFREE 8 145 #define DEFAULTOPT FS_OPTTIME 146 147 /* 148 * Grigoriy Orlov <gluk@ptci.ru> has done some extensive work to fine 149 * tune the layout preferences for directories within a filesystem. 150 * His algorithm can be tuned by adjusting the following parameters 151 * which tell the system the average file size and the average number 152 * of files per directory. These defaults are well selected for typical 153 * filesystems, but may need to be tuned for odd cases like filesystems 154 * being used for squid caches or news spools. 155 */ 156 #define AVFILESIZ 16384 /* expected average file size */ 157 #define AFPDIR 64 /* expected number of files per directory */ 158 159 /* 160 * The maximum number of snapshot nodes that can be associated 161 * with each filesystem. This limit affects only the number of 162 * snapshot files that can be recorded within the superblock so 163 * that they can be found when the filesystem is mounted. However, 164 * maintaining too many will slow the filesystem performance, so 165 * having this limit is a good idea. 166 * 167 * VALUE NOT IMPLEMENTED IN DragonFly(and very unlikely to ever be as there are 168 * much better options such as journaling), RESERVED FROM FreeBSD 5.x SO 169 * SUPERBLOCKS REMAIN COMPATIBLE FOR THE TIME BEING. WHY ARE WE YELLING ? 170 */ 171 #define FSMAXSNAP 20 172 173 /* 174 * Per cylinder group information; summarized in blocks allocated 175 * from first cylinder group data blocks. These blocks have to be 176 * read in from fs_csaddr (size fs_cssize) in addition to the 177 * super block. 178 */ 179 struct csum { 180 int32_t cs_ndir; /* number of directories */ 181 int32_t cs_nbfree; /* number of free blocks */ 182 int32_t cs_nifree; /* number of free inodes */ 183 int32_t cs_nffree; /* number of free frags */ 184 }; 185 186 /* 187 * Super block for an FFS filesystem. 188 */ 189 struct fs { 190 int32_t fs_firstfield; /* historic filesystem linked list, */ 191 int32_t fs_unused_1; /* used for incore super blocks */ 192 ufs_daddr_t fs_sblkno; /* addr of super-block in filesys */ 193 ufs_daddr_t fs_cblkno; /* offset of cyl-block in filesys */ 194 ufs_daddr_t fs_iblkno; /* offset of inode-blocks in filesys */ 195 ufs_daddr_t fs_dblkno; /* offset of first data after cg */ 196 int32_t fs_cgoffset; /* cylinder group offset in cylinder */ 197 int32_t fs_cgmask; /* used to calc mod fs_ntrak */ 198 ufs_time_t fs_time; /* last time written */ 199 int32_t fs_size; /* number of blocks in fs */ 200 int32_t fs_dsize; /* number of data blocks in fs */ 201 int32_t fs_ncg; /* number of cylinder groups */ 202 int32_t fs_bsize; /* size of basic blocks in fs */ 203 int32_t fs_fsize; /* size of frag blocks in fs */ 204 int32_t fs_frag; /* number of frags in a block in fs */ 205 /* these are configuration parameters */ 206 int32_t fs_minfree; /* minimum percentage of free blocks */ 207 int32_t fs_rotdelay; /* num of ms for optimal next block */ 208 int32_t fs_rps; /* disk revolutions per second */ 209 /* these fields can be computed from the others */ 210 int32_t fs_bmask; /* ``blkoff'' calc of blk offsets */ 211 int32_t fs_fmask; /* ``fragoff'' calc of frag offsets */ 212 int32_t fs_bshift; /* ``lblkno'' calc of logical blkno */ 213 int32_t fs_fshift; /* ``numfrags'' calc number of frags */ 214 /* these are configuration parameters */ 215 int32_t fs_maxcontig; /* max number of contiguous blks */ 216 int32_t fs_maxbpg; /* max number of blks per cyl group */ 217 /* these fields can be computed from the others */ 218 int32_t fs_fragshift; /* block to frag shift */ 219 int32_t fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */ 220 int32_t fs_sbsize; /* actual size of super block */ 221 int32_t fs_csmask; /* csum block offset (now unused) */ 222 int32_t fs_csshift; /* csum block number (now unused) */ 223 int32_t fs_nindir; /* value of NINDIR */ 224 int32_t fs_inopb; /* value of INOPB */ 225 int32_t fs_nspf; /* value of NSPF */ 226 /* yet another configuration parameter */ 227 int32_t fs_optim; /* optimization preference, see below */ 228 /* these fields are derived from the hardware */ 229 int32_t fs_npsect; /* # sectors/track including spares */ 230 int32_t fs_interleave; /* hardware sector interleave */ 231 int32_t fs_trackskew; /* sector 0 skew, per track */ 232 /* fs_id takes the space of the unused fs_headswitch and fs_trkseek fields */ 233 int32_t fs_id[2]; /* unique filesystem id */ 234 /* sizes determined by number of cylinder groups and their sizes */ 235 ufs_daddr_t fs_csaddr; /* blk addr of cyl grp summary area */ 236 int32_t fs_cssize; /* size of cyl grp summary area */ 237 int32_t fs_cgsize; /* cylinder group size */ 238 /* these fields are derived from the hardware */ 239 int32_t fs_ntrak; /* tracks per cylinder */ 240 int32_t fs_nsect; /* sectors per track */ 241 int32_t fs_spc; /* sectors per cylinder */ 242 /* this comes from the disk driver partitioning */ 243 int32_t fs_ncyl; /* cylinders in filesystem */ 244 /* these fields can be computed from the others */ 245 int32_t fs_cpg; /* cylinders per group */ 246 int32_t fs_ipg; /* inodes per group */ 247 int32_t fs_fpg; /* blocks per group * fs_frag */ 248 /* this data must be re-computed after crashes */ 249 struct csum fs_cstotal; /* cylinder summary information */ 250 /* these fields are cleared at mount time */ 251 int8_t fs_fmod; /* super block modified flag */ 252 int8_t fs_clean; /* filesystem is clean flag */ 253 int8_t fs_ronly; /* mounted read-only flag */ 254 int8_t fs_flags; /* see FS_ flags below */ 255 u_char fs_fsmnt[MAXMNTLEN]; /* name mounted on */ 256 u_char fs_volname[MAXVOLLEN]; /* volume name */ 257 u_int64_t fs_swuid; /* system-wide uid */ 258 int32_t fs_pad; /* due to alignment of fs_swuid */ 259 /* these fields retain the current block allocation info */ 260 int32_t fs_cgrotor; /* last cg searched */ 261 void *fs_ocsp[NOCSPTRS]; /* padding; was list of fs_cs buffers */ 262 uint8_t *fs_contigdirs; /* # of contiguously allocated dirs */ 263 struct csum *fs_csp; /* cg summary info buffer for fs_cs */ 264 int32_t *fs_maxcluster; /* max cluster in each cyl group */ 265 int32_t fs_cpc; /* cyl per cycle in postbl */ 266 int16_t fs_opostbl[16][8]; /* old rotation block list head */ 267 int32_t fs_snapinum[FSMAXSNAP];/* RESERVED FROM 5.x */ 268 int32_t fs_avgfilesize; /* expected average file size */ 269 int32_t fs_avgfpdir; /* expected # of files per directory */ 270 int32_t fs_sparecon[26]; /* reserved for future constants */ 271 int32_t fs_pendingblocks; /* RESERVED FROM 5.x */ 272 int32_t fs_pendinginodes; /* RESERVED FROM 5.x */ 273 int32_t fs_contigsumsize; /* size of cluster summary array */ 274 int32_t fs_maxsymlinklen; /* max length of an internal symlink */ 275 int32_t fs_inodefmt; /* format of on-disk inodes */ 276 uint64_t fs_maxfilesize; /* maximum representable file size */ 277 int64_t fs_qbmask; /* ~fs_bmask for use with 64-bit size */ 278 int64_t fs_qfmask; /* ~fs_fmask for use with 64-bit size */ 279 int32_t fs_state; /* validate fs_clean field */ 280 int32_t fs_postblformat; /* format of positional layout tables */ 281 int32_t fs_nrpos; /* number of rotational positions */ 282 int32_t fs_postbloff; /* (uint16) rotation block list head */ 283 int32_t fs_rotbloff; /* (uint8) blocks for each rotation */ 284 int32_t fs_magic; /* magic number */ 285 uint8_t fs_space[1]; /* list of blocks for each rotation */ 286 /* actually longer */ 287 }; 288 289 /* 290 * Filesystem identification 291 */ 292 #define FS_MAGIC 0x011954 /* the fast filesystem magic number */ 293 #define FS_OKAY 0x7c269d38 /* superblock checksum */ 294 #define FS_42INODEFMT -1 /* 4.2BSD inode format */ 295 #define FS_44INODEFMT 2 /* 4.4BSD inode format */ 296 297 /* 298 * Preference for optimization. 299 */ 300 #define FS_OPTTIME 0 /* minimize allocation time */ 301 #define FS_OPTSPACE 1 /* minimize disk fragmentation */ 302 303 /* 304 * Filesystem flags. 305 */ 306 #define FS_UNCLEAN 0x01 /* filesystem not clean at mount */ 307 #define FS_DOSOFTDEP 0x02 /* filesystem using soft dependencies */ 308 309 /* 310 * Rotational layout table format types 311 */ 312 #define FS_42POSTBLFMT -1 /* 4.2BSD rotational table format */ 313 #define FS_DYNAMICPOSTBLFMT 1 /* dynamic rotational table format */ 314 /* 315 * Macros for access to superblock array structures 316 */ 317 #define fs_postbl(fs, cylno) \ 318 (((fs)->fs_postblformat == FS_42POSTBLFMT) \ 319 ? ((fs)->fs_opostbl[cylno]) \ 320 : ((int16_t *)((uint8_t *)(fs) + \ 321 (fs)->fs_postbloff) + (cylno) * (fs)->fs_nrpos)) 322 #define fs_rotbl(fs) \ 323 (((fs)->fs_postblformat == FS_42POSTBLFMT) \ 324 ? ((fs)->fs_space) \ 325 : ((uint8_t *)((uint8_t *)(fs) + (fs)->fs_rotbloff))) 326 327 /* 328 * The size of a cylinder group is calculated by CGSIZE. The maximum size 329 * is limited by the fact that cylinder groups are at most one block. 330 * Its size is derived from the size of the maps maintained in the 331 * cylinder group and the (struct cg) size. 332 */ 333 #define CGSIZE(fs) \ 334 /* base cg */ (sizeof(struct cg) + sizeof(int32_t) + \ 335 /* blktot size */ (fs)->fs_cpg * sizeof(int32_t) + \ 336 /* blks size */ (fs)->fs_cpg * (fs)->fs_nrpos * sizeof(int16_t) + \ 337 /* inode map */ howmany((fs)->fs_ipg, NBBY) + \ 338 /* block map */ howmany((fs)->fs_cpg * (fs)->fs_spc / NSPF(fs), NBBY) +\ 339 /* if present */ ((fs)->fs_contigsumsize <= 0 ? 0 : \ 340 /* cluster sum */ (fs)->fs_contigsumsize * sizeof(int32_t) + \ 341 /* cluster map */ howmany((fs)->fs_cpg * (fs)->fs_spc / NSPB(fs), NBBY))) 342 343 /* 344 * Convert cylinder group to base address of its global summary info. 345 */ 346 #define fs_cs(fs, indx) fs_csp[indx] 347 348 /* 349 * Cylinder group block for a filesystem. 350 */ 351 #define CG_MAGIC 0x090255 352 struct cg { 353 int32_t cg_firstfield; /* historic cyl groups linked list */ 354 int32_t cg_magic; /* magic number */ 355 ufs_time_t cg_time; /* time last written */ 356 int32_t cg_cgx; /* we are the cgx'th cylinder group */ 357 int16_t cg_ncyl; /* number of cyl's this cg */ 358 int16_t cg_niblk; /* number of inode blocks this cg */ 359 int32_t cg_ndblk; /* number of data blocks this cg */ 360 struct csum cg_cs; /* cylinder summary information */ 361 int32_t cg_rotor; /* position of last used block */ 362 int32_t cg_frotor; /* position of last used frag */ 363 int32_t cg_irotor; /* position of last used inode */ 364 int32_t cg_frsum[MAXFRAG]; /* counts of available frags */ 365 int32_t cg_btotoff; /* (int32) block totals per cylinder */ 366 int32_t cg_boff; /* (uint16) free block positions */ 367 int32_t cg_iusedoff; /* (uint8) used inode map */ 368 int32_t cg_freeoff; /* (uint8) free block map */ 369 int32_t cg_nextfreeoff; /* (uint8) next available space */ 370 int32_t cg_clustersumoff; /* (uint32) counts of avail clusters */ 371 int32_t cg_clusteroff; /* (uint8) free cluster map */ 372 int32_t cg_nclusterblks; /* number of clusters this cg */ 373 int32_t cg_sparecon[13]; /* reserved for future use */ 374 uint8_t cg_space[1]; /* space for cylinder group maps */ 375 /* actually longer */ 376 }; 377 378 /* 379 * Macros for access to cylinder group array structures 380 */ 381 #define cg_blktot(cgp) \ 382 (((cgp)->cg_magic != CG_MAGIC) \ 383 ? (((struct ocg *)(cgp))->cg_btot) \ 384 : ((int32_t *)((uint8_t *)(cgp) + (cgp)->cg_btotoff))) 385 #define cg_blks(fs, cgp, cylno) \ 386 (((cgp)->cg_magic != CG_MAGIC) \ 387 ? (((struct ocg *)(cgp))->cg_b[cylno]) \ 388 : ((int16_t *)((uint8_t *)(cgp) + \ 389 (cgp)->cg_boff) + (cylno) * (fs)->fs_nrpos)) 390 #define cg_inosused(cgp) \ 391 (((cgp)->cg_magic != CG_MAGIC) \ 392 ? (((struct ocg *)(cgp))->cg_iused) \ 393 : ((uint8_t *)((uint8_t *)(cgp) + (cgp)->cg_iusedoff))) 394 #define cg_blksfree(cgp) \ 395 (((cgp)->cg_magic != CG_MAGIC) \ 396 ? (((struct ocg *)(cgp))->cg_free) \ 397 : ((uint8_t *)((uint8_t *)(cgp) + (cgp)->cg_freeoff))) 398 #define cg_chkmagic(cgp) \ 399 ((cgp)->cg_magic == CG_MAGIC || ((struct ocg *)(cgp))->cg_magic == CG_MAGIC) 400 #define cg_clustersfree(cgp) \ 401 ((uint8_t *)((uint8_t *)(cgp) + (cgp)->cg_clusteroff)) 402 #define cg_clustersum(cgp) \ 403 ((int32_t *)((uint8_t *)(cgp) + (cgp)->cg_clustersumoff)) 404 405 /* 406 * The following structure is defined 407 * for compatibility with old filesystems. 408 */ 409 struct ocg { 410 int32_t cg_firstfield; /* historic linked list of cyl groups */ 411 int32_t cg_unused_1; /* used for incore cyl groups */ 412 ufs_time_t cg_time; /* time last written */ 413 int32_t cg_cgx; /* we are the cgx'th cylinder group */ 414 int16_t cg_ncyl; /* number of cyl's this cg */ 415 int16_t cg_niblk; /* number of inode blocks this cg */ 416 int32_t cg_ndblk; /* number of data blocks this cg */ 417 struct csum cg_cs; /* cylinder summary information */ 418 int32_t cg_rotor; /* position of last used block */ 419 int32_t cg_frotor; /* position of last used frag */ 420 int32_t cg_irotor; /* position of last used inode */ 421 int32_t cg_frsum[8]; /* counts of available frags */ 422 int32_t cg_btot[32]; /* block totals per cylinder */ 423 int16_t cg_b[32][8]; /* positions of free blocks */ 424 uint8_t cg_iused[256]; /* used inode map */ 425 int32_t cg_magic; /* magic number */ 426 uint8_t cg_free[1]; /* free block map */ 427 /* actually longer */ 428 }; 429 430 /* 431 * Turn filesystem block numbers into disk block addresses. 432 * This maps filesystem blocks to device size blocks. 433 */ 434 #define fsbtodb(fs, b) ((b) << (fs)->fs_fsbtodb) 435 #define dbtofsb(fs, b) ((b) >> (fs)->fs_fsbtodb) 436 #define btofsb(fs, b) ((daddr_t)((b) >> ((fs)->fs_fsbtodb + DEV_BSHIFT))) 437 438 /* 439 * Cylinder group macros to locate things in cylinder groups. 440 * They calc filesystem addresses of cylinder group data structures. 441 */ 442 #define cgbase(fs, c) ((ufs_daddr_t)((fs)->fs_fpg * (c))) 443 #define cgdmin(fs, c) (cgstart(fs, c) + (fs)->fs_dblkno) /* 1st data */ 444 #define cgimin(fs, c) (cgstart(fs, c) + (fs)->fs_iblkno) /* inode blk */ 445 #define cgsblock(fs, c) (cgstart(fs, c) + (fs)->fs_sblkno) /* super blk */ 446 #define cgtod(fs, c) (cgstart(fs, c) + (fs)->fs_cblkno) /* cg block */ 447 #define cgstart(fs, c) \ 448 (cgbase(fs, c) + (fs)->fs_cgoffset * ((c) & ~((fs)->fs_cgmask))) 449 450 /* 451 * Macros for handling inode numbers: 452 * inode number to filesystem block offset. 453 * inode number to cylinder group number. 454 * inode number to filesystem block address. 455 */ 456 #define ino_to_cg(fs, x) ((x) / (fs)->fs_ipg) 457 #define ino_to_fsba(fs, x) \ 458 ((ufs_daddr_t)(cgimin(fs, ino_to_cg(fs, x)) + \ 459 (blkstofrags((fs), (((x) % (fs)->fs_ipg) / INOPB(fs)))))) 460 #define ino_to_fsbo(fs, x) ((x) % INOPB(fs)) 461 462 /* 463 * Give cylinder group number for a filesystem block. 464 * Give cylinder group block number for a filesystem block. 465 */ 466 #define dtog(fs, d) ((d) / (fs)->fs_fpg) 467 #define dtogd(fs, d) ((d) % (fs)->fs_fpg) 468 469 /* 470 * Extract the bits for a block from a map. 471 * Compute the cylinder and rotational position of a cyl block addr. 472 */ 473 #define blkmap(fs, map, loc) \ 474 (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag))) 475 #define cbtocylno(fs, bno) \ 476 ((bno) * NSPF(fs) / (fs)->fs_spc) 477 #define cbtorpos(fs, bno) \ 478 (((bno) * NSPF(fs) % (fs)->fs_spc / (fs)->fs_nsect * (fs)->fs_trackskew + \ 479 (bno) * NSPF(fs) % (fs)->fs_spc % (fs)->fs_nsect * (fs)->fs_interleave) % \ 480 (fs)->fs_nsect * (fs)->fs_nrpos / (fs)->fs_npsect) 481 482 /* 483 * The following macros optimize certain frequently calculated 484 * quantities by using shifts and masks in place of divisions 485 * modulos and multiplications. 486 */ 487 #define blkoff(fs, loc) /* calculates (loc % fs->fs_bsize) */ \ 488 ((loc) & (fs)->fs_qbmask) 489 #define fragoff(fs, loc) /* calculates (loc % fs->fs_fsize) */ \ 490 ((loc) & (fs)->fs_qfmask) 491 #define lblktosize(fs, blk) /* calculates ((off_t)blk * fs->fs_bsize) */ \ 492 ((off_t)(blk) << (fs)->fs_bshift) 493 /* 494 * These functions convert filesystem logical block numbers (typ 8K), 495 * filesystem block numbers (typ 1K), and disk block numbers to 64 bit 496 * offsets for the purposes of bread(), getblk(), etc. 497 * 498 * note: fs_nspf = number of sectors per fragment. For some reason 499 * completely lost to me the superblock doesn't actually store the disk 500 * block size. 501 */ 502 #define lblktodoff(fs, blk) ((off_t)(blk) << (fs)->fs_bshift) 503 #define fsbtodoff(fs, b) ((off_t)(b) << (fs)->fs_fshift) 504 #define dbtodoff(fs, b) ((off_t)(b) * ((fs)->fs_fsize / (fs)->fs_nspf)) 505 #define dofftofsb(fs, b) ((ufs_daddr_t)((b) >> (fs)->fs_fshift)) 506 507 /* Use this only when `blk' is known to be small, e.g., < UFS_NDADDR. */ 508 #define smalllblktosize(fs, blk) /* calculates (blk * fs->fs_bsize) */ \ 509 ((blk) << (fs)->fs_bshift) 510 #define lblkno(fs, loc) /* calculates (loc / fs->fs_bsize) */ \ 511 ((loc) >> (fs)->fs_bshift) 512 #define numfrags(fs, loc) /* calculates (loc / fs->fs_fsize) */ \ 513 ((loc) >> (fs)->fs_fshift) 514 #define blkroundup(fs, size) /* calculates roundup(size, fs->fs_bsize) */ \ 515 (((size) + (fs)->fs_qbmask) & (fs)->fs_bmask) 516 #define fragroundup(fs, size) /* calculates roundup(size, fs->fs_fsize) */ \ 517 (((size) + (fs)->fs_qfmask) & (fs)->fs_fmask) 518 #define fragstoblks(fs, frags) /* calculates (frags / fs->fs_frag) */ \ 519 ((frags) >> (fs)->fs_fragshift) 520 #define blkstofrags(fs, blks) /* calculates (blks * fs->fs_frag) */ \ 521 ((blks) << (fs)->fs_fragshift) 522 #define fragnum(fs, fsb) /* calculates (fsb % fs->fs_frag) */ \ 523 ((fsb) & ((fs)->fs_frag - 1)) 524 #define blknum(fs, fsb) /* calculates rounddown(fsb, fs->fs_frag) */ \ 525 ((fsb) &~ ((fs)->fs_frag - 1)) 526 527 /* 528 * Determine the number of available frags given a 529 * percentage to hold in reserve. 530 */ 531 #define freespace(fs, percentreserved) \ 532 (blkstofrags((fs), (fs)->fs_cstotal.cs_nbfree) + \ 533 (fs)->fs_cstotal.cs_nffree - \ 534 ((off_t)((fs)->fs_dsize) * (percentreserved) / 100)) 535 536 /* 537 * Determining the size of a file block in the filesystem. 538 */ 539 #define blksize(fs, ip, lbn) \ 540 (((lbn) >= UFS_NDADDR || \ 541 (ip)->i_size >= smalllblktosize(fs, (lbn) + 1)) \ 542 ? (fs)->fs_bsize \ 543 : (fragroundup(fs, blkoff(fs, (ip)->i_size)))) 544 #define dblksize(fs, dip, lbn) \ 545 (((lbn) >= UFS_NDADDR || \ 546 (dip)->di_size >= smalllblktosize(fs, (lbn) + 1)) \ 547 ? (fs)->fs_bsize \ 548 : (fragroundup(fs, blkoff(fs, (dip)->di_size)))) 549 #define sblksize(fs, size, lbn) \ 550 (((lbn) >= UFS_NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \ 551 ? (fs)->fs_bsize \ 552 : (fragroundup(fs, blkoff(fs, (size))))) 553 554 /* 555 * Extract the block size for the buffer cache buffer at offset (loc) 556 * relative to the current ip->i_size, or relative to a specific ip->i_size. 557 */ 558 #define blkoffsize(fs, ip, loc) blksize(fs, ip, lblkno(fs, loc)) 559 #define blkoffresize(fs, loc) sblksize(fs, loc, lblkno(fs, loc)) 560 561 /* 562 * Number of disk sectors per block/fragment; assumes DEV_BSIZE byte 563 * sector size. 564 */ 565 #define NSPB(fs) ((fs)->fs_nspf << (fs)->fs_fragshift) 566 #define NSPF(fs) ((fs)->fs_nspf) 567 568 /* 569 * Number of inodes in a secondary storage block/fragment. 570 */ 571 #define INOPB(fs) ((fs)->fs_inopb) 572 #define INOPF(fs) ((fs)->fs_inopb >> (fs)->fs_fragshift) 573 574 /* 575 * Number of indirects in a filesystem block. 576 */ 577 #define NINDIR(fs) ((fs)->fs_nindir) 578 579 extern int inside[], around[]; 580 extern u_char *fragtbl[]; 581 582 #endif /* !_VFS_UFS_FS_H_ */ 583