FreeBSD/Linux Kernel Cross Reference
sys/ufs/ffs/fs.h
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 * $FreeBSD$
35 */
36
37 #ifndef _UFS_FFS_FS_H_
38 #define _UFS_FFS_FS_H_
39
40 /*
41 * Each disk drive contains some number of file systems.
42 * A file system consists of a number of cylinder groups.
43 * Each cylinder group has inodes and data.
44 *
45 * A file system 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 file system 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 * The first boot and super blocks are given in absolute disk addresses.
62 * The byte-offset forms are preferred, as they don't imply a sector size.
63 */
64 #define BBSIZE 8192
65 #define SBSIZE 8192
66 #define BBOFF ((off_t)(0))
67 #define SBOFF ((off_t)(BBOFF + BBSIZE))
68 #define BBLOCK ((ufs_daddr_t)(0))
69 #define SBLOCK ((ufs_daddr_t)(BBLOCK + BBSIZE / DEV_BSIZE))
70
71 /*
72 * Addresses stored in inodes are capable of addressing fragments
73 * of `blocks'. File system blocks of at most size MAXBSIZE can
74 * be optionally broken into 2, 4, or 8 pieces, each of which is
75 * addressable; these pieces may be DEV_BSIZE, or some multiple of
76 * a DEV_BSIZE unit.
77 *
78 * Large files consist of exclusively large data blocks. To avoid
79 * undue wasted disk space, the last data block of a small file may be
80 * allocated as only as many fragments of a large block as are
81 * necessary. The file system format retains only a single pointer
82 * to such a fragment, which is a piece of a single large block that
83 * has been divided. The size of such a fragment is determinable from
84 * information in the inode, using the ``blksize(fs, ip, lbn)'' macro.
85 *
86 * The file system records space availability at the fragment level;
87 * to determine block availability, aligned fragments are examined.
88 */
89
90 /*
91 * MINBSIZE is the smallest allowable block size.
92 * In order to insure that it is possible to create files of size
93 * 2^32 with only two levels of indirection, MINBSIZE is set to 4096.
94 * MINBSIZE must be big enough to hold a cylinder group block,
95 * thus changes to (struct cg) must keep its size within MINBSIZE.
96 * Note that super blocks are always of size SBSIZE,
97 * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE.
98 */
99 #define MINBSIZE 4096
100
101 /*
102 * The path name on which the file system is mounted is maintained
103 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in
104 * the super block for this name.
105 */
106 #define MAXMNTLEN 512
107
108 /*
109 * The limit on the amount of summary information per file system
110 * is defined by MAXCSBUFS. It is currently parameterized for a
111 * size of 128 bytes (2 million cylinder groups on machines with
112 * 32-bit pointers, and 1 million on 64-bit machines). One pointer
113 * is taken away to point to an array of cluster sizes that is
114 * computed as cylinder groups are inspected.
115 */
116 #define MAXCSBUFS ((128 / sizeof(void *)) - 1)
117
118 /*
119 * A summary of contiguous blocks of various sizes is maintained
120 * in each cylinder group. Normally this is set by the initial
121 * value of fs_maxcontig. To conserve space, a maximum summary size
122 * is set by FS_MAXCONTIG.
123 */
124 #define FS_MAXCONTIG 16
125
126 /*
127 * MINFREE gives the minimum acceptable percentage of file system
128 * blocks which may be free. If the freelist drops below this level
129 * only the superuser may continue to allocate blocks. This may
130 * be set to 0 if no reserve of free blocks is deemed necessary,
131 * however throughput drops by fifty percent if the file system
132 * is run at between 95% and 100% full; thus the minimum default
133 * value of fs_minfree is 5%. However, to get good clustering
134 * performance, 10% is a better choice. hence we use 10% as our
135 * default value. With 10% free space, fragmentation is not a
136 * problem, so we choose to optimize for time.
137 */
138 #define MINFREE 8
139 #define DEFAULTOPT FS_OPTTIME
140
141 /*
142 * Per cylinder group information; summarized in blocks allocated
143 * from first cylinder group data blocks. These blocks have to be
144 * read in from fs_csaddr (size fs_cssize) in addition to the
145 * super block.
146 *
147 * N.B. sizeof(struct csum) must be a power of two in order for
148 * the ``fs_cs'' macro to work (see below).
149 */
150 struct csum {
151 int32_t cs_ndir; /* number of directories */
152 int32_t cs_nbfree; /* number of free blocks */
153 int32_t cs_nifree; /* number of free inodes */
154 int32_t cs_nffree; /* number of free frags */
155 };
156
157 /*
158 * Super block for an FFS file system.
159 */
160 struct fs {
161 int32_t fs_firstfield; /* historic file system linked list, */
162 int32_t fs_unused_1; /* used for incore super blocks */
163 ufs_daddr_t fs_sblkno; /* addr of super-block in filesys */
164 ufs_daddr_t fs_cblkno; /* offset of cyl-block in filesys */
165 ufs_daddr_t fs_iblkno; /* offset of inode-blocks in filesys */
166 ufs_daddr_t fs_dblkno; /* offset of first data after cg */
167 int32_t fs_cgoffset; /* cylinder group offset in cylinder */
168 int32_t fs_cgmask; /* used to calc mod fs_ntrak */
169 time_t fs_time; /* last time written */
170 int32_t fs_size; /* number of blocks in fs */
171 int32_t fs_dsize; /* number of data blocks in fs */
172 int32_t fs_ncg; /* number of cylinder groups */
173 int32_t fs_bsize; /* size of basic blocks in fs */
174 int32_t fs_fsize; /* size of frag blocks in fs */
175 int32_t fs_frag; /* number of frags in a block in fs */
176 /* these are configuration parameters */
177 int32_t fs_minfree; /* minimum percentage of free blocks */
178 int32_t fs_rotdelay; /* num of ms for optimal next block */
179 int32_t fs_rps; /* disk revolutions per second */
180 /* these fields can be computed from the others */
181 int32_t fs_bmask; /* ``blkoff'' calc of blk offsets */
182 int32_t fs_fmask; /* ``fragoff'' calc of frag offsets */
183 int32_t fs_bshift; /* ``lblkno'' calc of logical blkno */
184 int32_t fs_fshift; /* ``numfrags'' calc number of frags */
185 /* these are configuration parameters */
186 int32_t fs_maxcontig; /* max number of contiguous blks */
187 int32_t fs_maxbpg; /* max number of blks per cyl group */
188 /* these fields can be computed from the others */
189 int32_t fs_fragshift; /* block to frag shift */
190 int32_t fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */
191 int32_t fs_sbsize; /* actual size of super block */
192 int32_t fs_csmask; /* csum block offset */
193 int32_t fs_csshift; /* csum block number */
194 int32_t fs_nindir; /* value of NINDIR */
195 int32_t fs_inopb; /* value of INOPB */
196 int32_t fs_nspf; /* value of NSPF */
197 /* yet another configuration parameter */
198 int32_t fs_optim; /* optimization preference, see below */
199 /* these fields are derived from the hardware */
200 int32_t fs_npsect; /* # sectors/track including spares */
201 int32_t fs_interleave; /* hardware sector interleave */
202 int32_t fs_trackskew; /* sector 0 skew, per track */
203 /* fs_id takes the space of the unused fs_headswitch and fs_trkseek fields */
204 int32_t fs_id[2]; /* unique filesystem id */
205 /* sizes determined by number of cylinder groups and their sizes */
206 ufs_daddr_t fs_csaddr; /* blk addr of cyl grp summary area */
207 int32_t fs_cssize; /* size of cyl grp summary area */
208 int32_t fs_cgsize; /* cylinder group size */
209 /* these fields are derived from the hardware */
210 int32_t fs_ntrak; /* tracks per cylinder */
211 int32_t fs_nsect; /* sectors per track */
212 int32_t fs_spc; /* sectors per cylinder */
213 /* this comes from the disk driver partitioning */
214 int32_t fs_ncyl; /* cylinders in file system */
215 /* these fields can be computed from the others */
216 int32_t fs_cpg; /* cylinders per group */
217 int32_t fs_ipg; /* inodes per group */
218 int32_t fs_fpg; /* blocks per group * fs_frag */
219 /* this data must be re-computed after crashes */
220 struct csum fs_cstotal; /* cylinder summary information */
221 /* these fields are cleared at mount time */
222 int8_t fs_fmod; /* super block modified flag */
223 int8_t fs_clean; /* file system is clean flag */
224 int8_t fs_ronly; /* mounted read-only flag */
225 int8_t fs_flags; /* see FS_ flags below */
226 u_char fs_fsmnt[MAXMNTLEN]; /* name mounted on */
227 /* these fields retain the current block allocation info */
228 int32_t fs_cgrotor; /* last cg searched */
229 struct csum *fs_csp[MAXCSBUFS];/* list of fs_cs info buffers */
230 int32_t *fs_maxcluster; /* max cluster in each cyl group */
231 int32_t fs_cpc; /* cyl per cycle in postbl */
232 int16_t fs_opostbl[16][8]; /* old rotation block list head */
233 int32_t fs_sparecon[50]; /* reserved for future constants */
234 int32_t fs_contigsumsize; /* size of cluster summary array */
235 int32_t fs_maxsymlinklen; /* max length of an internal symlink */
236 int32_t fs_inodefmt; /* format of on-disk inodes */
237 u_int64_t fs_maxfilesize; /* maximum representable file size */
238 int64_t fs_qbmask; /* ~fs_bmask for use with 64-bit size */
239 int64_t fs_qfmask; /* ~fs_fmask for use with 64-bit size */
240 int32_t fs_state; /* validate fs_clean field */
241 int32_t fs_postblformat; /* format of positional layout tables */
242 int32_t fs_nrpos; /* number of rotational positions */
243 int32_t fs_postbloff; /* (u_int16) rotation block list head */
244 int32_t fs_rotbloff; /* (u_int8) blocks for each rotation */
245 int32_t fs_magic; /* magic number */
246 u_int8_t fs_space[1]; /* list of blocks for each rotation */
247 /* actually longer */
248 };
249
250 /*
251 * Filesystem identification
252 */
253 #define FS_MAGIC 0x011954 /* the fast filesystem magic number */
254 #define FS_OKAY 0x7c269d38 /* superblock checksum */
255 #define FS_42INODEFMT -1 /* 4.2BSD inode format */
256 #define FS_44INODEFMT 2 /* 4.4BSD inode format */
257
258 /*
259 * Preference for optimization.
260 */
261 #define FS_OPTTIME 0 /* minimize allocation time */
262 #define FS_OPTSPACE 1 /* minimize disk fragmentation */
263
264 /*
265 * Filesystem flags.
266 */
267 #define FS_UNCLEAN 0x01 /* filesystem not clean at mount */
268 #define FS_DOSOFTDEP 0x02 /* filesystem using soft dependencies */
269
270 /*
271 * Rotational layout table format types
272 */
273 #define FS_42POSTBLFMT -1 /* 4.2BSD rotational table format */
274 #define FS_DYNAMICPOSTBLFMT 1 /* dynamic rotational table format */
275 /*
276 * Macros for access to superblock array structures
277 */
278 #define fs_postbl(fs, cylno) \
279 (((fs)->fs_postblformat == FS_42POSTBLFMT) \
280 ? ((fs)->fs_opostbl[cylno]) \
281 : ((int16_t *)((u_int8_t *)(fs) + \
282 (fs)->fs_postbloff) + (cylno) * (fs)->fs_nrpos))
283 #define fs_rotbl(fs) \
284 (((fs)->fs_postblformat == FS_42POSTBLFMT) \
285 ? ((fs)->fs_space) \
286 : ((u_int8_t *)((u_int8_t *)(fs) + (fs)->fs_rotbloff)))
287
288 /*
289 * The size of a cylinder group is calculated by CGSIZE. The maximum size
290 * is limited by the fact that cylinder groups are at most one block.
291 * Its size is derived from the size of the maps maintained in the
292 * cylinder group and the (struct cg) size.
293 */
294 #define CGSIZE(fs) \
295 /* base cg */ (sizeof(struct cg) + sizeof(int32_t) + \
296 /* blktot size */ (fs)->fs_cpg * sizeof(int32_t) + \
297 /* blks size */ (fs)->fs_cpg * (fs)->fs_nrpos * sizeof(int16_t) + \
298 /* inode map */ howmany((fs)->fs_ipg, NBBY) + \
299 /* block map */ howmany((fs)->fs_cpg * (fs)->fs_spc / NSPF(fs), NBBY) +\
300 /* if present */ ((fs)->fs_contigsumsize <= 0 ? 0 : \
301 /* cluster sum */ (fs)->fs_contigsumsize * sizeof(int32_t) + \
302 /* cluster map */ howmany((fs)->fs_cpg * (fs)->fs_spc / NSPB(fs), NBBY)))
303
304 /*
305 * Convert cylinder group to base address of its global summary info.
306 *
307 * N.B. This macro assumes that sizeof(struct csum) is a power of two.
308 */
309 #define fs_cs(fs, indx) \
310 fs_csp[(indx) >> (fs)->fs_csshift][(indx) & ~(fs)->fs_csmask]
311
312 /*
313 * Cylinder group block for a file system.
314 */
315 #define CG_MAGIC 0x090255
316 struct cg {
317 int32_t cg_firstfield; /* historic cyl groups linked list */
318 int32_t cg_magic; /* magic number */
319 time_t cg_time; /* time last written */
320 int32_t cg_cgx; /* we are the cgx'th cylinder group */
321 int16_t cg_ncyl; /* number of cyl's this cg */
322 int16_t cg_niblk; /* number of inode blocks this cg */
323 int32_t cg_ndblk; /* number of data blocks this cg */
324 struct csum cg_cs; /* cylinder summary information */
325 int32_t cg_rotor; /* position of last used block */
326 int32_t cg_frotor; /* position of last used frag */
327 int32_t cg_irotor; /* position of last used inode */
328 int32_t cg_frsum[MAXFRAG]; /* counts of available frags */
329 int32_t cg_btotoff; /* (int32) block totals per cylinder */
330 int32_t cg_boff; /* (u_int16) free block positions */
331 int32_t cg_iusedoff; /* (u_int8) used inode map */
332 int32_t cg_freeoff; /* (u_int8) free block map */
333 int32_t cg_nextfreeoff; /* (u_int8) next available space */
334 int32_t cg_clustersumoff; /* (u_int32) counts of avail clusters */
335 int32_t cg_clusteroff; /* (u_int8) free cluster map */
336 int32_t cg_nclusterblks; /* number of clusters this cg */
337 int32_t cg_sparecon[13]; /* reserved for future use */
338 u_int8_t cg_space[1]; /* space for cylinder group maps */
339 /* actually longer */
340 };
341
342 /*
343 * Macros for access to cylinder group array structures
344 */
345 #define cg_blktot(cgp) \
346 (((cgp)->cg_magic != CG_MAGIC) \
347 ? (((struct ocg *)(cgp))->cg_btot) \
348 : ((int32_t *)((u_int8_t *)(cgp) + (cgp)->cg_btotoff)))
349 #define cg_blks(fs, cgp, cylno) \
350 (((cgp)->cg_magic != CG_MAGIC) \
351 ? (((struct ocg *)(cgp))->cg_b[cylno]) \
352 : ((int16_t *)((u_int8_t *)(cgp) + \
353 (cgp)->cg_boff) + (cylno) * (fs)->fs_nrpos))
354 #define cg_inosused(cgp) \
355 (((cgp)->cg_magic != CG_MAGIC) \
356 ? (((struct ocg *)(cgp))->cg_iused) \
357 : ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_iusedoff)))
358 #define cg_blksfree(cgp) \
359 (((cgp)->cg_magic != CG_MAGIC) \
360 ? (((struct ocg *)(cgp))->cg_free) \
361 : ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_freeoff)))
362 #define cg_chkmagic(cgp) \
363 ((cgp)->cg_magic == CG_MAGIC || ((struct ocg *)(cgp))->cg_magic == CG_MAGIC)
364 #define cg_clustersfree(cgp) \
365 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_clusteroff))
366 #define cg_clustersum(cgp) \
367 ((int32_t *)((u_int8_t *)(cgp) + (cgp)->cg_clustersumoff))
368
369 /*
370 * The following structure is defined
371 * for compatibility with old file systems.
372 */
373 struct ocg {
374 int32_t cg_firstfield; /* historic linked list of cyl groups */
375 int32_t cg_unused_1; /* used for incore cyl groups */
376 time_t cg_time; /* time last written */
377 int32_t cg_cgx; /* we are the cgx'th cylinder group */
378 int16_t cg_ncyl; /* number of cyl's this cg */
379 int16_t cg_niblk; /* number of inode blocks this cg */
380 int32_t cg_ndblk; /* number of data blocks this cg */
381 struct csum cg_cs; /* cylinder summary information */
382 int32_t cg_rotor; /* position of last used block */
383 int32_t cg_frotor; /* position of last used frag */
384 int32_t cg_irotor; /* position of last used inode */
385 int32_t cg_frsum[8]; /* counts of available frags */
386 int32_t cg_btot[32]; /* block totals per cylinder */
387 int16_t cg_b[32][8]; /* positions of free blocks */
388 u_int8_t cg_iused[256]; /* used inode map */
389 int32_t cg_magic; /* magic number */
390 u_int8_t cg_free[1]; /* free block map */
391 /* actually longer */
392 };
393
394 /*
395 * Turn file system block numbers into disk block addresses.
396 * This maps file system blocks to device size blocks.
397 */
398 #define fsbtodb(fs, b) ((b) << (fs)->fs_fsbtodb)
399 #define dbtofsb(fs, b) ((b) >> (fs)->fs_fsbtodb)
400
401 /*
402 * Cylinder group macros to locate things in cylinder groups.
403 * They calc file system addresses of cylinder group data structures.
404 */
405 #define cgbase(fs, c) ((ufs_daddr_t)((fs)->fs_fpg * (c)))
406 #define cgdmin(fs, c) (cgstart(fs, c) + (fs)->fs_dblkno) /* 1st data */
407 #define cgimin(fs, c) (cgstart(fs, c) + (fs)->fs_iblkno) /* inode blk */
408 #define cgsblock(fs, c) (cgstart(fs, c) + (fs)->fs_sblkno) /* super blk */
409 #define cgtod(fs, c) (cgstart(fs, c) + (fs)->fs_cblkno) /* cg block */
410 #define cgstart(fs, c) \
411 (cgbase(fs, c) + (fs)->fs_cgoffset * ((c) & ~((fs)->fs_cgmask)))
412
413 /*
414 * Macros for handling inode numbers:
415 * inode number to file system block offset.
416 * inode number to cylinder group number.
417 * inode number to file system block address.
418 */
419 #define ino_to_cg(fs, x) ((x) / (fs)->fs_ipg)
420 #define ino_to_fsba(fs, x) \
421 ((ufs_daddr_t)(cgimin(fs, ino_to_cg(fs, x)) + \
422 (blkstofrags((fs), (((x) % (fs)->fs_ipg) / INOPB(fs))))))
423 #define ino_to_fsbo(fs, x) ((x) % INOPB(fs))
424
425 /*
426 * Give cylinder group number for a file system block.
427 * Give cylinder group block number for a file system block.
428 */
429 #define dtog(fs, d) ((d) / (fs)->fs_fpg)
430 #define dtogd(fs, d) ((d) % (fs)->fs_fpg)
431
432 /*
433 * Extract the bits for a block from a map.
434 * Compute the cylinder and rotational position of a cyl block addr.
435 */
436 #define blkmap(fs, map, loc) \
437 (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag)))
438 #define cbtocylno(fs, bno) \
439 ((bno) * NSPF(fs) / (fs)->fs_spc)
440 #define cbtorpos(fs, bno) \
441 (((bno) * NSPF(fs) % (fs)->fs_spc / (fs)->fs_nsect * (fs)->fs_trackskew + \
442 (bno) * NSPF(fs) % (fs)->fs_spc % (fs)->fs_nsect * (fs)->fs_interleave) % \
443 (fs)->fs_nsect * (fs)->fs_nrpos / (fs)->fs_npsect)
444
445 /*
446 * The following macros optimize certain frequently calculated
447 * quantities by using shifts and masks in place of divisions
448 * modulos and multiplications.
449 */
450 #define blkoff(fs, loc) /* calculates (loc % fs->fs_bsize) */ \
451 ((loc) & (fs)->fs_qbmask)
452 #define fragoff(fs, loc) /* calculates (loc % fs->fs_fsize) */ \
453 ((loc) & (fs)->fs_qfmask)
454 #define lblktosize(fs, blk) /* calculates ((off_t)blk * fs->fs_bsize) */ \
455 ((off_t)(blk) << (fs)->fs_bshift)
456 /* Use this only when `blk' is known to be small, e.g., < NDADDR. */
457 #define smalllblktosize(fs, blk) /* calculates (blk * fs->fs_bsize) */ \
458 ((blk) << (fs)->fs_bshift)
459 #define lblkno(fs, loc) /* calculates (loc / fs->fs_bsize) */ \
460 ((loc) >> (fs)->fs_bshift)
461 #define numfrags(fs, loc) /* calculates (loc / fs->fs_fsize) */ \
462 ((loc) >> (fs)->fs_fshift)
463 #define blkroundup(fs, size) /* calculates roundup(size, fs->fs_bsize) */ \
464 (((size) + (fs)->fs_qbmask) & (fs)->fs_bmask)
465 #define fragroundup(fs, size) /* calculates roundup(size, fs->fs_fsize) */ \
466 (((size) + (fs)->fs_qfmask) & (fs)->fs_fmask)
467 #define fragstoblks(fs, frags) /* calculates (frags / fs->fs_frag) */ \
468 ((frags) >> (fs)->fs_fragshift)
469 #define blkstofrags(fs, blks) /* calculates (blks * fs->fs_frag) */ \
470 ((blks) << (fs)->fs_fragshift)
471 #define fragnum(fs, fsb) /* calculates (fsb % fs->fs_frag) */ \
472 ((fsb) & ((fs)->fs_frag - 1))
473 #define blknum(fs, fsb) /* calculates rounddown(fsb, fs->fs_frag) */ \
474 ((fsb) &~ ((fs)->fs_frag - 1))
475
476 /*
477 * Determine the number of available frags given a
478 * percentage to hold in reserve.
479 */
480 #define freespace(fs, percentreserved) \
481 (blkstofrags((fs), (fs)->fs_cstotal.cs_nbfree) + \
482 (fs)->fs_cstotal.cs_nffree - ((fs)->fs_dsize * (percentreserved) / 100))
483
484 /*
485 * Determining the size of a file block in the file system.
486 */
487 #define blksize(fs, ip, lbn) \
488 (((lbn) >= NDADDR || (ip)->i_size >= smalllblktosize(fs, (lbn) + 1)) \
489 ? (fs)->fs_bsize \
490 : (fragroundup(fs, blkoff(fs, (ip)->i_size))))
491 #define dblksize(fs, dip, lbn) \
492 (((lbn) >= NDADDR || (dip)->di_size >= smalllblktosize(fs, (lbn) + 1)) \
493 ? (fs)->fs_bsize \
494 : (fragroundup(fs, blkoff(fs, (dip)->di_size))))
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 extern int inside[], around[];
520 extern u_char *fragtbl[];
521
522 #endif
Cache object: 446660f25a620c97e37b11d0fca2116d
|