ffs.h (21239B)
1 /* $Id: //depot/blt/srv/vfs/drivers/ffs/ffs.h#1 $ */ 2 /* OpenBSD: fs.h,v 1.8 1998/11/29 00:45:30 art Exp */ 3 /* NetBSD: fs.h,v 1.6 1995/04/12 21:21:02 mycroft Exp */ 4 5 /* 6 * Copyright (c) 1982, 1986, 1993 7 * The Regents of the University of California. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by the University of 20 * California, Berkeley and its contributors. 21 * 4. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * @(#)fs.h 8.10 (Berkeley) 10/27/94 38 */ 39 40 #ifndef FFS_H 41 #define FFS_H 42 43 #ifndef VFS_SANDBOX 44 #include <blt/types.h> 45 #else 46 #include "types.h" 47 #endif 48 49 /* 50 * Each disk drive contains some number of file systems. 51 * A file system consists of a number of cylinder groups. 52 * Each cylinder group has inodes and data. 53 * 54 * A file system is described by its super-block, which in turn 55 * describes the cylinder groups. The super-block is critical 56 * data and is replicated in each cylinder group to protect against 57 * catastrophic loss. This is done at `newfs' time and the critical 58 * super-block data does not change, so the copies need not be 59 * referenced further unless disaster strikes. 60 * 61 * For file system fs, the offsets of the various blocks of interest 62 * are given in the super block as: 63 * [fs->fs_sblkno] Super-block 64 * [fs->fs_cblkno] Cylinder group block 65 * [fs->fs_iblkno] Inode blocks 66 * [fs->fs_dblkno] Data blocks 67 * The beginning of cylinder group cg in fs, is given by 68 * the ``cgbase(fs, cg)'' macro. 69 * 70 * The first boot and super blocks are given in absolute disk addresses. 71 * The byte-offset forms are preferred, as they don't imply a sector size. 72 */ 73 #define DEV_BSIZE 512 74 #define BBSIZE 8192 75 #define SBSIZE 8192 76 #define BLKSIZE 8192 77 #define BBOFF ((off_t)(0)) 78 #define SBOFF ((off_t)(BBOFF + BBSIZE)) 79 #define BBLOCK ((uint32)(0)) 80 #define SBLOCK ((uint32)(BBLOCK + BBSIZE / DEV_BSIZE)) 81 82 /* 83 * Addresses stored in inodes are capable of addressing fragments 84 * of `blocks'. File system blocks of at most size MAXBSIZE can 85 * be optionally broken into 2, 4, or 8 pieces, each of which is 86 * addressible; these pieces may be DEV_BSIZE, or some multiple of 87 * a DEV_BSIZE unit. 88 * 89 * Large files consist of exclusively large data blocks. To avoid 90 * undue wasted disk space, the last data block of a small file may be 91 * allocated as only as many fragments of a large block as are 92 * necessary. The file system format retains only a single pointer 93 * to such a fragment, which is a piece of a single large block that 94 * has been divided. The size of such a fragment is determinable from 95 * information in the inode, using the ``blksize(fs, ip, lbn)'' macro. 96 * 97 * The file system records space availability at the fragment level; 98 * to determine block availability, aligned fragments are examined. 99 */ 100 101 /* 102 * MINBSIZE is the smallest allowable block size. 103 * In order to insure that it is possible to create files of size 104 * 2^32 with only two levels of indirection, MINBSIZE is set to 4096. 105 * MINBSIZE must be big enough to hold a cylinder group block, 106 * thus changes to (struct cg) must keep its size within MINBSIZE. 107 * Note that super blocks are always of size SBSIZE, 108 * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE. 109 */ 110 #define MINBSIZE 4096 111 112 /* 113 * The path name on which the file system is mounted is maintained 114 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in 115 * the super block for this name. 116 */ 117 #define MAXMNTLEN 512 118 119 /* 120 * The limit on the amount of summary information per file system 121 * is defined by MAXCSBUFS. It is currently parameterized for a 122 * size of 128 bytes (2 million cylinder groups on machines with 123 * 32-bit pointers, and 1 million on 64-bit machines). One pointer 124 * is taken away to point to an array of cluster sizes that is 125 * computed as cylinder groups are inspected. 126 */ 127 #define MAXCSBUFS ((128 / sizeof(void *)) - 1) 128 129 /* 130 * A summary of contiguous blocks of various sizes is maintained 131 * in each cylinder group. Normally this is set by the initial 132 * value of fs_maxcontig. To conserve space, a maximum summary size 133 * is set by FS_MAXCONTIG. 134 */ 135 #define FS_MAXCONTIG 16 136 137 /* 138 * MINFREE gives the minimum acceptable percentage of file system 139 * blocks which may be free. If the freelist drops below this level 140 * only the superuser may continue to allocate blocks. This may 141 * be set to 0 if no reserve of free blocks is deemed necessary, 142 * however throughput drops by fifty percent if the file system 143 * is run at between 95% and 100% full; thus the minimum default 144 * value of fs_minfree is 5%. However, to get good clustering 145 * performance, 10% is a better choice. hence we use 10% as our 146 * default value. With 10% free space, fragmentation is not a 147 * problem, so we choose to optimize for time. 148 */ 149 #define MINFREE 5 150 #define DEFAULTOPT FS_OPTTIME 151 152 /* 153 * The file system is made out of blocks of at most MAXBSIZE units, with 154 * smaller units (fragments) only in the last direct block. MAXBSIZE 155 * primarily determines the size of buffers in the buffer pool. It may be 156 * made larger without any effect on existing file systems; however making 157 * it smaller makes some file systems unmountable. 158 */ 159 #define MAXFRAG 8 160 161 /* 162 * Per cylinder group information; summarized in blocks allocated 163 * from first cylinder group data blocks. These blocks have to be 164 * read in from fs_csaddr (size fs_cssize) in addition to the 165 * super block. 166 * 167 * N.B. sizeof(struct csum) must be a power of two in order for 168 * the ``fs_cs'' macro to work (see below). 169 */ 170 struct csum { 171 int32 cs_ndir; /* number of directories */ 172 int32 cs_nbfree; /* number of free blocks */ 173 int32 cs_nifree; /* number of free inodes */ 174 int32 cs_nffree; /* number of free frags */ 175 }; 176 177 /* 178 * Super block for an FFS file system. 179 */ 180 struct ffs_super { 181 int32 fs_firstfield; /* historic file system linked list, */ 182 int32 fs_unused_1; /* used for incore super blocks */ 183 uint32 fs_sblkno; /* addr of super-block in filesys */ 184 uint32 fs_cblkno; /* offset of cyl-block in filesys */ 185 uint32 fs_iblkno; /* offset of inode-blocks in filesys */ 186 uint32 fs_dblkno; /* offset of first data after cg */ 187 int32 fs_cgoffset; /* cylinder group offset in cylinder */ 188 int32 fs_cgmask; /* used to calc mod fs_ntrak */ 189 time_t fs_time; /* last time written */ 190 int32 fs_size; /* number of blocks in fs */ 191 int32 fs_dsize; /* number of data blocks in fs */ 192 int32 fs_ncg; /* number of cylinder groups */ 193 int32 fs_bsize; /* size of basic blocks in fs */ 194 int32 fs_fsize; /* size of frag blocks in fs */ 195 int32 fs_frag; /* number of frags in a block in fs */ 196 /* these are configuration parameters */ 197 int32 fs_minfree; /* minimum percentage of free blocks */ 198 int32 fs_rotdelay; /* num of ms for optimal next block */ 199 int32 fs_rps; /* disk revolutions per second */ 200 /* these fields can be computed from the others */ 201 int32 fs_bmask; /* ``blkoff'' calc of blk offsets */ 202 int32 fs_fmask; /* ``fragoff'' calc of frag offsets */ 203 int32 fs_bshift; /* ``lblkno'' calc of logical blkno */ 204 int32 fs_fshift; /* ``numfrags'' calc number of frags */ 205 /* these are configuration parameters */ 206 int32 fs_maxcontig; /* max number of contiguous blks */ 207 int32 fs_maxbpg; /* max number of blks per cyl group */ 208 /* these fields can be computed from the others */ 209 int32 fs_fragshift; /* block to frag shift */ 210 int32 fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */ 211 int32 fs_sbsize; /* actual size of super block */ 212 int32 fs_csmask; /* csum block offset */ 213 int32 fs_csshift; /* csum block number */ 214 int32 fs_nindir; /* value of NINDIR */ 215 int32 fs_inopb; /* value of INOPB */ 216 int32 fs_nspf; /* value of NSPF */ 217 /* yet another configuration parameter */ 218 int32 fs_optim; /* optimization preference, see below */ 219 /* these fields are derived from the hardware */ 220 int32 fs_npsect; /* # sectors/track including spares */ 221 int32 fs_interleave; /* hardware sector interleave */ 222 int32 fs_trackskew; /* sector 0 skew, per track */ 223 /* fs_id takes the space of the unused fs_headswitch and fs_trkseek fields */ 224 int32 fs_id[2]; /* unique filesystem id */ 225 /* sizes determined by number of cylinder groups and their sizes */ 226 uint32 fs_csaddr; /* blk addr of cyl grp summary area */ 227 int32 fs_cssize; /* size of cyl grp summary area */ 228 int32 fs_cgsize; /* cylinder group size */ 229 /* these fields are derived from the hardware */ 230 int32 fs_ntrak; /* tracks per cylinder */ 231 int32 fs_nsect; /* sectors per track */ 232 int32 fs_spc; /* sectors per cylinder */ 233 /* this comes from the disk driver partitioning */ 234 int32 fs_ncyl; /* cylinders in file system */ 235 /* these fields can be computed from the others */ 236 int32 fs_cpg; /* cylinders per group */ 237 int32 fs_ipg; /* inodes per group */ 238 int32 fs_fpg; /* blocks per group * fs_frag */ 239 /* this data must be re-computed after crashes */ 240 struct csum fs_cstotal; /* cylinder summary information */ 241 /* these fields are cleared at mount time */ 242 int8 fs_fmod; /* super block modified flag */ 243 int8 fs_clean; /* file system is clean flag */ 244 int8 fs_ronly; /* mounted read-only flag */ 245 int8 fs_flags; /* see FS_ below */ 246 uint8 fs_fsmnt[MAXMNTLEN]; /* name mounted on */ 247 /* these fields retain the current block allocation info */ 248 int32 fs_cgrotor; /* last cg searched */ 249 struct csum *fs_csp[MAXCSBUFS];/* list of fs_cs info buffers */ 250 int32 *fs_maxcluster; /* max cluster in each cyl group */ 251 int32 fs_cpc; /* cyl per cycle in postbl */ 252 int16 fs_opostbl[16][8]; /* old rotation block list head */ 253 int32 fs_sparecon[49]; /* reserved for future constants */ 254 time_t fs_fscktime; /* last time fsck(8)ed */ 255 int32 fs_contigsumsize; /* size of cluster summary array */ 256 int32 fs_maxsymlinklen; /* max length of an internal symlink */ 257 int32 fs_inodefmt; /* format of on-disk inodes */ 258 uint64 fs_maxfilesize; /* maximum representable file size */ 259 int64 fs_qbmask; /* ~fs_bmask - for use with quad size */ 260 int64 fs_qfmask; /* ~fs_fmask - for use with quad size */ 261 int32 fs_state; /* validate fs_clean field */ 262 int32 fs_postblformat; /* format of positional layout tables */ 263 int32 fs_nrpos; /* number of rotational positions */ 264 int32 fs_postbloff; /* (u_int16) rotation block list head */ 265 int32 fs_rotbloff; /* (u_int8) blocks for each rotation */ 266 int32 fs_magic; /* magic number */ 267 uint8 fs_space[1]; /* list of blocks for each rotation */ 268 /* actually longer */ 269 }; 270 271 /* 272 * Filesystem identification 273 */ 274 #define FS_MAGIC 0x011954 /* the fast filesystem magic number */ 275 #define FS_OKAY 0x7c269d38 /* superblock checksum */ 276 #define FS_42INODEFMT -1 /* 4.2BSD inode format */ 277 #define FS_44INODEFMT 2 /* 4.4BSD inode format */ 278 279 /* 280 * Filesystem clean flags 281 */ 282 #define FS_ISCLEAN 0x01 283 #define FS_WASCLEAN 0x02 284 285 /* 286 * Preference for optimization. 287 */ 288 #define FS_OPTTIME 0 /* minimize allocation time */ 289 #define FS_OPTSPACE 1 /* minimize disk fragmentation */ 290 291 /* 292 * Filesystem flags. 293 */ 294 #define FS_UNCLEAN 0x01 /* filesystem not clean at mount */ 295 #define FS_DOSOFTDEP 0x02 /* filesystem using soft dependencies */ 296 297 /* 298 * Rotational layout table format types 299 */ 300 #define FS_42POSTBLFMT -1 /* 4.2BSD rotational table format */ 301 #define FS_DYNAMICPOSTBLFMT 1 /* dynamic rotational table format */ 302 /* 303 * Macros for access to superblock array structures 304 */ 305 #define fs_postbl(fs, cylno) \ 306 (((fs)->fs_postblformat == FS_42POSTBLFMT) \ 307 ? ((fs)->fs_opostbl[cylno]) \ 308 : ((int16 *)((uint8 *)(fs) + \ 309 (fs)->fs_postbloff) + (cylno) * (fs)->fs_nrpos)) 310 #define fs_rotbl(fs) \ 311 (((fs)->fs_postblformat == FS_42POSTBLFMT) \ 312 ? ((fs)->fs_space) \ 313 : ((uint8 *)((uint8 *)(fs) + (fs)->fs_rotbloff))) 314 315 /* 316 * The size of a cylinder group is calculated by CGSIZE. The maximum size 317 * is limited by the fact that cylinder groups are at most one block. 318 * Its size is derived from the size of the maps maintained in the 319 * cylinder group and the (struct cg) size. 320 */ 321 #define CGSIZE(fs) \ 322 /* base cg */ (sizeof(struct cg) + sizeof(int32) + \ 323 /* blktot size */ (fs)->fs_cpg * sizeof(int32) + \ 324 /* blks size */ (fs)->fs_cpg * (fs)->fs_nrpos * sizeof(int16) + \ 325 /* inode map */ howmany((fs)->fs_ipg, NBBY) + \ 326 /* block map */ howmany((fs)->fs_cpg * (fs)->fs_spc / NSPF(fs), NBBY) +\ 327 /* if present */ ((fs)->fs_contigsumsize <= 0 ? 0 : \ 328 /* cluster sum */ (fs)->fs_contigsumsize * sizeof(int32) + \ 329 /* cluster map */ howmany((fs)->fs_cpg * (fs)->fs_spc / NSPB(fs), NBBY))) 330 331 /* 332 * Convert cylinder group to base address of its global summary info. 333 * 334 * N.B. This macro assumes that sizeof(struct csum) is a power of two. 335 */ 336 #define fs_cs(fs, indx) \ 337 fs_csp[(indx) >> (fs)->fs_csshift][(indx) & ~(fs)->fs_csmask] 338 339 /* 340 * Cylinder group block for a file system. 341 */ 342 #define CG_MAGIC 0x090255 343 struct cg { 344 int32 cg_firstfield; /* historic cyl groups linked list */ 345 int32 cg_magic; /* magic number */ 346 time_t cg_time; /* time last written */ 347 int32 cg_cgx; /* we are the cgx'th cylinder group */ 348 int16 cg_ncyl; /* number of cyl's this cg */ 349 int16 cg_niblk; /* number of inode blocks this cg */ 350 int32 cg_ndblk; /* number of data blocks this cg */ 351 struct csum cg_cs; /* cylinder summary information */ 352 int32 cg_rotor; /* position of last used block */ 353 int32 cg_frotor; /* position of last used frag */ 354 int32 cg_irotor; /* position of last used inode */ 355 int32 cg_frsum[MAXFRAG]; /* counts of available frags */ 356 int32 cg_btotoff; /* (int32) block totals per cylinder */ 357 int32 cg_boff; /* (u_int16) free block positions */ 358 int32 cg_iusedoff; /* (u_int8) used inode map */ 359 int32 cg_freeoff; /* (u_int8) free block map */ 360 int32 cg_nextfreeoff; /* (u_int8) next available space */ 361 int32 cg_clustersumoff; /* (u_int32) counts of avail clusters */ 362 int32 cg_clusteroff; /* (u_int8) free cluster map */ 363 int32 cg_nclusterblks; /* number of clusters this cg */ 364 int32 cg_sparecon[13]; /* reserved for future use */ 365 uint8 cg_space[1]; /* space for cylinder group maps */ 366 /* actually longer */ 367 }; 368 369 /* 370 * Macros for access to cylinder group array structures 371 */ 372 #define cg_blktot(cgp) \ 373 (((cgp)->cg_magic != CG_MAGIC) \ 374 ? (((struct ocg *)(cgp))->cg_btot) \ 375 : ((int32 *)((uint8 *)(cgp) + (cgp)->cg_btotoff))) 376 #define cg_blks(fs, cgp, cylno) \ 377 (((cgp)->cg_magic != CG_MAGIC) \ 378 ? (((struct ocg *)(cgp))->cg_b[cylno]) \ 379 : ((int16 *)((uint8 *)(cgp) + \ 380 (cgp)->cg_boff) + (cylno) * (fs)->fs_nrpos)) 381 #define cg_inosused(cgp) \ 382 (((cgp)->cg_magic != CG_MAGIC) \ 383 ? (((struct ocg *)(cgp))->cg_iused) \ 384 : ((uint8 *)((uint8 *)(cgp) + (cgp)->cg_iusedoff))) 385 #define cg_blksfree(cgp) \ 386 (((cgp)->cg_magic != CG_MAGIC) \ 387 ? (((struct ocg *)(cgp))->cg_free) \ 388 : ((uint8 *)((uint8 *)(cgp) + (cgp)->cg_freeoff))) 389 #define cg_chkmagic(cgp) \ 390 ((cgp)->cg_magic == CG_MAGIC || ((struct ocg *)(cgp))->cg_magic == CG_MAGIC) 391 #define cg_clustersfree(cgp) \ 392 ((uint8 *)((uint8 *)(cgp) + (cgp)->cg_clusteroff)) 393 #define cg_clustersum(cgp) \ 394 ((int32 *)((uint8 *)(cgp) + (cgp)->cg_clustersumoff)) 395 396 /* 397 * Turn file system block numbers into disk block addresses. 398 * This maps file system blocks to device size blocks. 399 */ 400 #define fsbtodb(fs, b) ((b) << (fs)->fs_fsbtodb) 401 #define dbtofsb(fs, b) ((b) >> (fs)->fs_fsbtodb) 402 403 /* 404 * Cylinder group macros to locate things in cylinder groups. 405 * They calc file system addresses of cylinder group data structures. 406 */ 407 #define cgbase(fs, c) ((uint32)((fs)->fs_fpg * (c))) 408 #define cgdmin(fs, c) (cgstart(fs, c) + (fs)->fs_dblkno) /* 1st data */ 409 #define cgimin(fs, c) (cgstart(fs, c) + (fs)->fs_iblkno) /* inode blk */ 410 #define cgsblock(fs, c) (cgstart(fs, c) + (fs)->fs_sblkno) /* super blk */ 411 #define cgtod(fs, c) (cgstart(fs, c) + (fs)->fs_cblkno) /* cg block */ 412 #define cgstart(fs, c) \ 413 (cgbase(fs, c) + (fs)->fs_cgoffset * ((c) & ~((fs)->fs_cgmask))) 414 415 /* 416 * Macros for handling inode numbers: 417 * inode number to file system block offset. 418 * inode number to cylinder group number. 419 * inode number to file system block address. 420 */ 421 #define ino_to_cg(fs, x) ((x) / (fs)->fs_ipg) 422 #define ino_to_fsba(fs, x) \ 423 ((uint32)(cgimin((fs), ino_to_cg((fs), x)) + \ 424 (blkstofrags((fs), (((x) % (fs)->fs_ipg) / INOPB(fs)))))) 425 #define ino_to_fsbo(fs, x) ((x) % INOPB(fs)) 426 427 /* 428 * Give cylinder group number for a file system block. 429 * Give cylinder group block number for a file system block. 430 */ 431 #define dtog(fs, d) ((d) / (fs)->fs_fpg) 432 #define dtogd(fs, d) ((d) % (fs)->fs_fpg) 433 434 /* 435 * Extract the bits for a block from a map. 436 * Compute the cylinder and rotational position of a cyl block addr. 437 */ 438 #define blkmap(fs, map, loc) \ 439 (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag))) 440 #define cbtocylno(fs, bno) \ 441 ((bno) * NSPF(fs) / (fs)->fs_spc) 442 #define cbtorpos(fs, bno) \ 443 (((bno) * NSPF(fs) % (fs)->fs_spc / (fs)->fs_nsect * (fs)->fs_trackskew + \ 444 (bno) * NSPF(fs) % (fs)->fs_spc % (fs)->fs_nsect * (fs)->fs_interleave) % \ 445 (fs)->fs_nsect * (fs)->fs_nrpos / (fs)->fs_npsect) 446 447 /* 448 * The following macros optimize certain frequently calculated 449 * quantities by using shifts and masks in place of divisions 450 * modulos and multiplications. 451 */ 452 #define blkoff(fs, loc) /* calculates (loc % fs->fs_bsize) */ \ 453 ((loc) & (fs)->fs_qbmask) 454 #define fragoff(fs, loc) /* calculates (loc % fs->fs_fsize) */ \ 455 ((loc) & (fs)->fs_qfmask) 456 #define lblktosize(fs, blk) /* calculates (blk * fs->fs_bsize) */ \ 457 ((blk) << (fs)->fs_bshift) 458 #define lblkno(fs, loc) /* calculates (loc / fs->fs_bsize) */ \ 459 ((loc) >> (fs)->fs_bshift) 460 #define numfrags(fs, loc) /* calculates (loc / fs->fs_fsize) */ \ 461 ((loc) >> (fs)->fs_fshift) 462 #define blkroundup(fs, size) /* calculates roundup(size, fs->fs_bsize) */ \ 463 (((size) + (fs)->fs_qbmask) & (fs)->fs_bmask) 464 #define fragroundup(fs, size) /* calculates roundup(size, fs->fs_fsize) */ \ 465 (((size) + (fs)->fs_qfmask) & (fs)->fs_fmask) 466 #define fragstoblks(fs, frags) /* calculates (frags / fs->fs_frag) */ \ 467 ((frags) >> (fs)->fs_fragshift) 468 #define blkstofrags(fs, blks) /* calculates (blks * fs->fs_frag) */ \ 469 ((blks) << (fs)->fs_fragshift) 470 #define fragnum(fs, fsb) /* calculates (fsb % fs->fs_frag) */ \ 471 ((fsb) & ((fs)->fs_frag - 1)) 472 #define blknum(fs, fsb) /* calculates rounddown(fsb, fs->fs_frag) */ \ 473 ((fsb) &~ ((fs)->fs_frag - 1)) 474 475 /* 476 * Determine the number of available frags given a 477 * percentage to hold in reserve. 478 */ 479 #define freespace(fs, percentreserved) \ 480 (blkstofrags((fs), (fs)->fs_cstotal.cs_nbfree) + \ 481 (fs)->fs_cstotal.cs_nffree - ((fs)->fs_dsize * (percentreserved) / 100)) 482 483 /* 484 * Determining the size of a file block in the file system. 485 */ 486 #define blksize(fs, ip, lbn) \ 487 (((lbn) >= NDADDR || (ip)->i_ffs_size >= ((lbn) + 1) << (fs)->fs_bshift) \ 488 ? (fs)->fs_bsize \ 489 : (fragroundup(fs, blkoff(fs, (ip)->i_ffs_size)))) 490 #define dblksize(fs, dip, lbn) \ 491 (((lbn) >= NDADDR || (dip)->di_size >= ((lbn) + 1) << (fs)->fs_bshift) \ 492 ? (fs)->fs_bsize \ 493 : (fragroundup(fs, blkoff(fs, (dip)->di_size)))) 494 495 #define sblksize(fs, size, lbn) \ 496 (((lbn) >= NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \ 497 ? (fs)->fs_bsize \ 498 : (fragroundup(fs, blkoff(fs, (size))))) 499 500 501 /* 502 * Number of disk sectors per block/fragment; assumes DEV_BSIZE byte 503 * sector size. 504 */ 505 #define NSPB(fs) ((fs)->fs_nspf << (fs)->fs_fragshift) 506 #define NSPF(fs) ((fs)->fs_nspf) 507 508 /* 509 * Number of inodes in a secondary storage block/fragment. 510 */ 511 #define INOPB(fs) ((fs)->fs_inopb) 512 #define INOPF(fs) ((fs)->fs_inopb >> (fs)->fs_fragshift) 513 514 /* 515 * Number of indirects in a file system block. 516 */ 517 #define NINDIR(fs) ((fs)->fs_nindir) 518 519 #endif 520