1 /* $OpenBSD: fs.h,v 1.32 2007/06/01 07:03:27 otto Exp $ */
2 /* $NetBSD: fs.h,v 1.6 1995/04/12 21:21:02 mycroft Exp $ */
3
4 /*
5 * Copyright (c) 1982, 1986, 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * @(#)fs.h 8.10 (Berkeley) 10/27/94
33 */
34
35 /*
36 * Each disk drive contains some number of file systems.
37 * A file system consists of a number of cylinder groups.
38 * Each cylinder group has inodes and data.
39 *
40 * A file system is described by its super-block, which in turn
41 * describes the cylinder groups. The super-block is critical
42 * data and is replicated in each cylinder group to protect against
43 * catastrophic loss. This is done at `newfs' time and the critical
44 * super-block data does not change, so the copies need not be
45 * referenced further unless disaster strikes.
46 *
47 * For file system fs, the offsets of the various blocks of interest
48 * are given in the super block as:
49 * [fs->fs_sblkno] Super-block
50 * [fs->fs_cblkno] Cylinder group block
51 * [fs->fs_iblkno] Inode blocks
52 * [fs->fs_dblkno] Data blocks
53 * The beginning of cylinder group cg in fs, is given by
54 * the ``cgbase(fs, cg)'' macro.
55 *
56 * The first boot and super blocks are given in absolute disk addresses.
57 * The byte-offset forms are preferred, as they don't imply a sector size.
58 */
59 #define BBSIZE 8192
60 #define SBSIZE 8192
61 #define BBOFF ((off_t)(0))
62 #define SBOFF ((off_t)(BBOFF + BBSIZE))
63 #define BBLOCK ((daddr_t)(0))
64 #define SBLOCK ((daddr_t)(BBLOCK + BBSIZE / DEV_BSIZE))
65 #define SBLOCK_UFS1 8192
66 #define SBLOCK_UFS2 65536
67 #define SBLOCK_PIGGY 262144
68 #define SBLOCKSIZE 8192
69 #define SBLOCKSEARCH \
70 { SBLOCK_UFS2, SBLOCK_UFS1, SBLOCK_PIGGY, -1 }
71
72 /*
73 * Addresses stored in inodes are capable of addressing fragments
74 * of `blocks'. File system blocks of at most size MAXBSIZE can
75 * be optionally broken into 2, 4, or 8 pieces, each of which is
76 * addressible; these pieces may be DEV_BSIZE, or some multiple of
77 * a DEV_BSIZE unit.
78 *
79 * Large files consist of exclusively large data blocks. To avoid
80 * undue wasted disk space, the last data block of a small file may be
81 * allocated as only as many fragments of a large block as are
82 * necessary. The file system format retains only a single pointer
83 * to such a fragment, which is a piece of a single large block that
84 * has been divided. The size of such a fragment is determinable from
85 * information in the inode, using the ``blksize(fs, ip, lbn)'' macro.
86 *
87 * The file system records space availability at the fragment level;
88 * to determine block availability, aligned fragments are examined.
89 */
90
91 /*
92 * MINBSIZE is the smallest allowable block size.
93 * In order to insure that it is possible to create files of size
94 * 2^32 with only two levels of indirection, MINBSIZE is set to 4096.
95 * MINBSIZE must be big enough to hold a cylinder group block,
96 * thus changes to (struct cg) must keep its size within MINBSIZE.
97 * Note that super blocks are always of size SBSIZE,
98 * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE.
99 */
100 #define MINBSIZE 4096
101
102 /*
103 * The path name on which the file system is mounted is maintained
104 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in
105 * the super block for this name.
106 */
107 #define MAXMNTLEN 468
108
109 /*
110 * The volume name for this file system is kept in fs_volname.
111 * MAXVOLLEN defines the length of the buffer allocated.
112 */
113 #define MAXVOLLEN 32
114
115 /*
116 * There is a 128-byte region in the superblock reserved for in-core
117 * pointers to summary information. Originally this included an array
118 * of pointers to blocks of struct csum; now there are just three
119 * pointers and the remaining space is padded with fs_ocsp[].
120 *
121 * NOCSPTRS determines the size of this padding. One pointer (fs_csp)
122 * is taken away to point to a contiguous array of struct csum for
123 * all cylinder groups; a second (fs_maxcluster) points to an array
124 * of cluster sizes that is computed as cylinder groups are inspected,
125 * and the third points to an array that tracks the creation of new
126 * directories.
127 */
128 #define NOCSPTRS ((128 / sizeof(void *)) - 4)
129
130 /*
131 * A summary of contiguous blocks of various sizes is maintained
132 * in each cylinder group. Normally this is set by the initial
133 * value of fs_maxcontig. To conserve space, a maximum summary size
134 * is set by FS_MAXCONTIG.
135 */
136 #define FS_MAXCONTIG 16
137
138 /*
139 * MINFREE gives the minimum acceptable percentage of file system
140 * blocks which may be free. If the freelist drops below this level
141 * only the superuser may continue to allocate blocks. This may
142 * be set to 0 if no reserve of free blocks is deemed necessary,
143 * however throughput drops by fifty percent if the file system
144 * is run at between 95% and 100% full; thus the minimum default
145 * value of fs_minfree is 5%. However, to get good clustering
146 * performance, 10% is a better choice. With 5% free space,
147 * fragmentation is not a problem, so we choose to optimize for time.
148 */
149 #define MINFREE 5
150 #define DEFAULTOPT FS_OPTTIME
151
152 /*
153 * The directory preference algorithm(dirpref) can be tuned by adjusting
154 * the following parameters which tell the system the average file size
155 * and the average number of files per directory. These defaults are well
156 * selected for typical filesystems, but may need to be tuned for odd
157 * cases like filesystems being used for sqiud caches or news spools.
158 */
159 #define AVFILESIZ 16384 /* expected average file size */
160 #define AFPDIR 64 /* expected number of files per directory */
161
162 /*
163 * Size of superblock space reserved for snapshots.
164 */
165 #define FSMAXSNAP 20
166
167 /*
168 * Per cylinder group information; summarized in blocks allocated
169 * from first cylinder group data blocks. These blocks have to be
170 * read in from fs_csaddr (size fs_cssize) in addition to the
171 * super block.
172 */
173 struct csum {
174 int32_t cs_ndir; /* number of directories */
175 int32_t cs_nbfree; /* number of free blocks */
176 int32_t cs_nifree; /* number of free inodes */
177 int32_t cs_nffree; /* number of free frags */
178 };
179
180 struct csum_total {
181 int64_t cs_ndir; /* number of directories */
182 int64_t cs_nbfree; /* number of free blocks */
183 int64_t cs_nifree; /* number of free inodes */
184 int64_t cs_nffree; /* number of free frags */
185 int64_t cs_spare[4]; /* future expansion */
186 };
187
188 /*
189 * Super block for an FFS file system.
190 */
191 struct fs {
192 int32_t fs_firstfield; /* historic file system linked list, */
193 int32_t fs_unused_1; /* used for incore super blocks */
194 int32_t fs_sblkno; /* addr of super-block / frags */
195 int32_t fs_cblkno; /* offset of cyl-block / frags */
196 int32_t fs_iblkno; /* offset of inode-blocks / frags */
197 int32_t fs_dblkno; /* offset of first data / frags */
198 int32_t fs_cgoffset; /* cylinder group offset in cylinder */
199 int32_t fs_cgmask; /* used to calc mod fs_ntrak */
200 int32_t fs_ffs1_time; /* last time written */
201 int32_t fs_ffs1_size; /* # of blocks in fs / frags */
202 int32_t fs_ffs1_dsize; /* # of data blocks in fs */
203 int32_t fs_ncg; /* # of cylinder groups */
204 int32_t fs_bsize; /* size of basic blocks / bytes */
205 int32_t fs_fsize; /* size of frag blocks / bytes */
206 int32_t fs_frag; /* # of frags in a block in fs */
207 /* these are configuration parameters */
208 int32_t fs_minfree; /* minimum percentage of free blocks */
209 int32_t fs_rotdelay; /* # of ms for optimal next block */
210 int32_t fs_rps; /* disk revolutions per second */
211 /* these fields can be computed from the others */
212 int32_t fs_bmask; /* ``blkoff'' calc of blk offsets */
213 int32_t fs_fmask; /* ``fragoff'' calc of frag offsets */
214 int32_t fs_bshift; /* ``lblkno'' calc of logical blkno */
215 int32_t fs_fshift; /* ``numfrags'' calc # of frags */
216 /* these are configuration parameters */
217 int32_t fs_maxcontig; /* max # of contiguous blks */
218 int32_t fs_maxbpg; /* max # of blks per cyl group */
219 /* these fields can be computed from the others */
220 int32_t fs_fragshift; /* block to frag shift */
221 int32_t fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */
222 int32_t fs_sbsize; /* actual size of super block */
223 int32_t fs_csmask; /* csum block offset (now unused) */
224 int32_t fs_csshift; /* csum block number (now unused) */
225 int32_t fs_nindir; /* value of NINDIR */
226 int32_t fs_inopb; /* inodes per file system block */
227 int32_t fs_nspf; /* value of NSPF */
228 /* yet another configuration parameter */
229 int32_t fs_optim; /* optimization preference, see below */
230 /* these fields are derived from the hardware */
231 int32_t fs_npsect; /* # sectors/track including spares */
232 int32_t fs_interleave; /* hardware sector interleave */
233 int32_t fs_trackskew; /* sector 0 skew, per track */
234 /* fs_id takes the space of the unused fs_headswitch and fs_trkseek fields */
235 int32_t fs_id[2]; /* unique filesystem id */
236 /* sizes determined by number of cylinder groups and their sizes */
237 int32_t fs_ffs1_csaddr; /* blk addr of cyl grp summary area */
238 int32_t fs_cssize; /* cyl grp summary area size / bytes */
239 int32_t fs_cgsize; /* cyl grp block size / bytes */
240 /* these fields are derived from the hardware */
241 int32_t fs_ntrak; /* tracks per cylinder */
242 int32_t fs_nsect; /* sectors per track */
243 int32_t fs_spc; /* sectors per cylinder */
244 /* this comes from the disk driver partitioning */
245 int32_t fs_ncyl; /* cylinders in file system */
246 /* these fields can be computed from the others */
247 int32_t fs_cpg; /* cylinders per group */
248 int32_t fs_ipg; /* inodes per group */
249 int32_t fs_fpg; /* blocks per group * fs_frag */
250 /* this data must be re-computed after crashes */
251 struct csum fs_ffs1_cstotal; /* cylinder summary information */
252 /* these fields are cleared at mount time */
253 int8_t fs_fmod; /* super block modified flag */
254 int8_t fs_clean; /* file system is clean flag */
255 int8_t fs_ronly; /* mounted read-only flag */
256 int8_t fs_ffs1_flags; /* see FS_ below */
257 u_char fs_fsmnt[MAXMNTLEN]; /* name mounted on */
258 u_char fs_volname[MAXVOLLEN]; /* volume name */
259 u_int64_t fs_swuid; /* system-wide uid */
260 int32_t fs_pad; /* due to alignment of fs_swuid */
261 /* these fields retain the current block allocation info */
262 int32_t fs_cgrotor; /* last cg searched */
263 void *fs_ocsp[NOCSPTRS]; /* padding; was list of fs_cs buffers */
264 u_int8_t *fs_contigdirs; /* # of contiguously allocated dirs */
265 struct csum *fs_csp; /* cg summary info buffer for fs_cs */
266 int32_t *fs_maxcluster; /* max cluster in each cyl group */
267 u_char *fs_active; /* reserved for snapshots */
268 int32_t fs_cpc; /* cyl per cycle in postbl */
269 /* this area is only allocated if fs_ffs1_flags & FS_FLAGS_UPDATED */
270 int32_t fs_maxbsize; /* maximum blocking factor permitted */
271 int64_t fs_spareconf64[17]; /* old rotation block list head */
272 int64_t fs_sblockloc; /* offset of standard super block */
273 struct csum_total fs_cstotal; /* cylinder summary information */
274 int64_t fs_time; /* time last written */
275 int64_t fs_size; /* number of blocks in fs */
276 int64_t fs_dsize; /* number of data blocks in fs */
277 int64_t fs_csaddr; /* blk addr of cyl grp summary area */
278 int64_t fs_pendingblocks; /* blocks in process of being freed */
279 int32_t fs_pendinginodes; /* inodes in process of being freed */
280 int32_t fs_snapinum[FSMAXSNAP];/* space reserved for snapshots */
281 /* back to stuff that has been around a while */
282 int32_t fs_avgfilesize; /* expected average file size */
283 int32_t fs_avgfpdir; /* expected # of files per directory */
284 int32_t fs_sparecon[26]; /* reserved for future constants */
285 u_int32_t fs_flags; /* see FS_ flags below */
286 int32_t fs_fscktime; /* last time fsck(8)ed */
287 int32_t fs_contigsumsize; /* size of cluster summary array */
288 int32_t fs_maxsymlinklen; /* max length of an internal symlink */
289 int32_t fs_inodefmt; /* format of on-disk inodes */
290 u_int64_t fs_maxfilesize; /* maximum representable file size */
291 int64_t fs_qbmask; /* ~fs_bmask - for use with quad size */
292 int64_t fs_qfmask; /* ~fs_fmask - for use with quad size */
293 int32_t fs_state; /* validate fs_clean field */
294 int32_t fs_postblformat; /* format of positional layout tables */
295 int32_t fs_nrpos; /* number of rotational positions */
296 int32_t fs_postbloff; /* (u_int16) rotation block list head */
297 int32_t fs_rotbloff; /* (u_int8) blocks for each rotation */
298 int32_t fs_magic; /* magic number */
299 u_int8_t fs_space[1]; /* list of blocks for each rotation */
300 /* actually longer */
301 };
302
303 /*
304 * Filesystem identification
305 */
306 #define FS_MAGIC 0x011954 /* the fast filesystem magic number */
307 #define FS_UFS1_MAGIC 0x011954 /* the fast filesystem magic number */
308 #define FS_UFS2_MAGIC 0x19540119 /* UFS fast filesystem magic number */
309 #define FS_OKAY 0x7c269d38 /* superblock checksum */
310 #define FS_42INODEFMT -1 /* 4.2BSD inode format */
311 #define FS_44INODEFMT 2 /* 4.4BSD inode format */
312
313 /*
314 * Filesystem clean flags
315 */
316 #define FS_ISCLEAN 0x01
317 #define FS_WASCLEAN 0x02
318
319 /*
320 * Preference for optimization.
321 */
322 #define FS_OPTTIME 0 /* minimize allocation time */
323 #define FS_OPTSPACE 1 /* minimize disk fragmentation */
324
325 /*
326 * Filesystem flags.
327 */
328 #define FS_UNCLEAN 0x01 /* filesystem not clean at mount */
329 #define FS_DOSOFTDEP 0x02 /* filesystem using soft dependencies */
330 /*
331 * The following flag is used to detect a FFS1 file system that had its flags
332 * moved to the new (FFS2) location for compatibility.
333 */
334 #define FS_FLAGS_UPDATED 0x80 /* file system has FFS2-like flags */
335
336 /*
337 * Rotational layout table format types
338 */
339 #define FS_42POSTBLFMT -1 /* 4.2BSD rotational table format */
340 #define FS_DYNAMICPOSTBLFMT 1 /* dynamic rotational table format */
341 /*
342 * Macros for access to superblock array structures
343 */
344 #define fs_rotbl(fs) \
345 (((fs)->fs_postblformat == FS_42POSTBLFMT) \
346 ? ((fs)->fs_space) \
347 : ((u_int8_t *)((u_int8_t *)(fs) + (fs)->fs_rotbloff)))
348
349 /*
350 * The size of a cylinder group is calculated by CGSIZE. The maximum size
351 * is limited by the fact that cylinder groups are at most one block.
352 * Its size is derived from the size of the maps maintained in the
353 * cylinder group and the (struct cg) size.
354 */
355 #define CGSIZE(fs) \
356 /* base cg */ (sizeof(struct cg) + sizeof(int32_t) + \
357 /* blktot size */ (fs)->fs_cpg * sizeof(int32_t) + \
358 /* blks size */ (fs)->fs_cpg * (fs)->fs_nrpos * sizeof(int16_t) + \
359 /* inode map */ howmany((fs)->fs_ipg, NBBY) + \
360 /* block map */ howmany((fs)->fs_fpg, NBBY) + \
361 /* if present */ ((fs)->fs_contigsumsize <= 0 ? 0 : \
362 /* cluster sum */ (fs)->fs_contigsumsize * sizeof(int32_t) + \
363 /* cluster map */ howmany(fragstoblks(fs, (fs)->fs_fpg), NBBY)))
364
365 /*
366 * Convert cylinder group to base address of its global summary info.
367 */
368 #define fs_cs(fs, indx) fs_csp[indx]
369
370 /*
371 * Cylinder group block for a file system.
372 */
373 #define CG_MAGIC 0x090255
374 struct cg {
375 int32_t cg_firstfield; /* historic cyl groups linked list */
376 int32_t cg_magic; /* magic number */
377 int32_t cg_time; /* time last written */
378 int32_t cg_cgx; /* we are the cgx'th cylinder group */
379 int16_t cg_ncyl; /* number of cyl's this cg */
380 int16_t cg_niblk; /* number of inode blocks this cg */
381 int32_t cg_ndblk; /* number of data blocks this cg */
382 struct csum cg_cs; /* cylinder summary information */
383 int32_t cg_rotor; /* position of last used block */
384 int32_t cg_frotor; /* position of last used frag */
385 int32_t cg_irotor; /* position of last used inode */
386 int32_t cg_frsum[MAXFRAG]; /* counts of available frags */
387 int32_t cg_btotoff; /* (int32) block totals per cylinder */
388 int32_t cg_boff; /* (u_int16) free block positions */
389 int32_t cg_iusedoff; /* (u_int8) used inode map */
390 int32_t cg_freeoff; /* (u_int8) free block map */
391 int32_t cg_nextfreeoff; /* (u_int8) next available space */
392 int32_t cg_clustersumoff; /* (u_int32) counts of avail clusters */
393 int32_t cg_clusteroff; /* (u_int8) free cluster map */
394 int32_t cg_nclusterblks; /* number of clusters this cg */
395 int32_t cg_ffs2_niblk; /* number of inode blocks this cg */
396 int32_t cg_initediblk; /* last initialized inode */
397 int32_t cg_sparecon32[3]; /* reserved for future use */
398 int64_t cg_ffs2_time; /* time last written */
399 int64_t cg_sparecon64[3]; /* reserved for future use */
400 /* actually longer */
401 };
402
403 /*
404 * Macros for access to cylinder group array structures
405 */
406 #define cg_blktot(cgp) \
407 (((cgp)->cg_magic != CG_MAGIC) \
408 ? (((struct ocg *)(cgp))->cg_btot) \
409 : ((int32_t *)((u_int8_t *)(cgp) + (cgp)->cg_btotoff)))
410 #define cg_blks(fs, cgp, cylno) \
411 (((cgp)->cg_magic != CG_MAGIC) \
412 ? (((struct ocg *)(cgp))->cg_b[cylno]) \
413 : ((int16_t *)((u_int8_t *)(cgp) + \
414 (cgp)->cg_boff) + (cylno) * (fs)->fs_nrpos))
415 #define cg_inosused(cgp) \
416 (((cgp)->cg_magic != CG_MAGIC) \
417 ? (((struct ocg *)(cgp))->cg_iused) \
418 : ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_iusedoff)))
419 #define cg_blksfree(cgp) \
420 (((cgp)->cg_magic != CG_MAGIC) \
421 ? (((struct ocg *)(cgp))->cg_free) \
422 : ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_freeoff)))
423 #define cg_chkmagic(cgp) \
424 ((cgp)->cg_magic == CG_MAGIC || ((struct ocg *)(cgp))->cg_magic == CG_MAGIC)
425 #define cg_clustersfree(cgp) \
426 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_clusteroff))
427 #define cg_clustersum(cgp) \
428 ((int32_t *)((u_int8_t *)(cgp) + (cgp)->cg_clustersumoff))
429
430 /*
431 * The following structure is defined
432 * for compatibility with old file systems.
433 */
434 struct ocg {
435 int32_t cg_firstfield; /* historic linked list of cyl groups */
436 int32_t cg_unused_1; /* used for incore cyl groups */
437 int32_t cg_time; /* time last written */
438 int32_t cg_cgx; /* we are the cgx'th cylinder group */
439 int16_t cg_ncyl; /* number of cyl's this cg */
440 int16_t cg_niblk; /* number of inode blocks this cg */
441 int32_t cg_ndblk; /* number of data blocks this cg */
442 struct csum cg_cs; /* cylinder summary information */
443 int32_t cg_rotor; /* position of last used block */
444 int32_t cg_frotor; /* position of last used frag */
445 int32_t cg_irotor; /* position of last used inode */
446 int32_t cg_frsum[8]; /* counts of available frags */
447 int32_t cg_btot[32]; /* block totals per cylinder */
448 int16_t cg_b[32][8]; /* positions of free blocks */
449 u_int8_t cg_iused[256]; /* used inode map */
450 int32_t cg_magic; /* magic number */
451 u_int8_t cg_free[1]; /* free block map */
452 /* actually longer */
453 };
454
455 /*
456 * Turn file system block numbers into disk block addresses.
457 * This maps file system blocks to device size blocks.
458 */
459 #define fsbtodb(fs, b) ((b) << (fs)->fs_fsbtodb)
460 #define dbtofsb(fs, b) ((b) >> (fs)->fs_fsbtodb)
461
462 /*
463 * Cylinder group macros to locate things in cylinder groups.
464 * They calc file system addresses of cylinder group data structures.
465 */
466 #define cgbase(fs, c) ((daddr_t)((fs)->fs_fpg * (c)))
467 #define cgdmin(fs, c) (cgstart(fs, c) + (fs)->fs_dblkno) /* 1st data */
468 #define cgimin(fs, c) (cgstart(fs, c) + (fs)->fs_iblkno) /* inode blk */
469 #define cgsblock(fs, c) (cgstart(fs, c) + (fs)->fs_sblkno) /* super blk */
470 #define cgtod(fs, c) (cgstart(fs, c) + (fs)->fs_cblkno) /* cg block */
471 #define cgstart(fs, c) \
472 (cgbase(fs, c) + (fs)->fs_cgoffset * ((c) & ~((fs)->fs_cgmask)))
473
474 /*
475 * Macros for handling inode numbers:
476 * inode number to file system block offset.
477 * inode number to cylinder group number.
478 * inode number to file system block address.
479 */
480 #define ino_to_cg(fs, x) ((x) / (fs)->fs_ipg)
481 #define ino_to_fsba(fs, x) \
482 ((daddr_t)(cgimin(fs, ino_to_cg(fs, x)) + \
483 (blkstofrags((fs), (((x) % (fs)->fs_ipg) / INOPB(fs))))))
484 #define ino_to_fsbo(fs, x) ((x) % INOPB(fs))
485
486 /*
487 * Give cylinder group number for a file system block.
488 * Give frag block number in cylinder group for a file system block.
489 */
490 #define dtog(fs, d) ((d) / (fs)->fs_fpg)
491 #define dtogd(fs, d) ((d) % (fs)->fs_fpg)
492
493 /*
494 * Extract the bits for a block from a map.
495 * Compute the cylinder and rotational position of a cyl block addr.
496 */
497 #define blkmap(fs, map, loc) \
498 (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag)))
499 #define cbtocylno(fs, bno) \
500 (fsbtodb(fs, bno) / (fs)->fs_spc)
501 #define cbtorpos(fs, bno) \
502 ((fs)->fs_nrpos <= 1 ? 0 : \
503 (fsbtodb(fs, bno) % (fs)->fs_spc / (fs)->fs_nsect * (fs)->fs_trackskew + \
504 fsbtodb(fs, bno) % (fs)->fs_spc % (fs)->fs_nsect * (fs)->fs_interleave) % \
505 (fs)->fs_nsect * (fs)->fs_nrpos / (fs)->fs_npsect)
506
507 /*
508 * The following macros optimize certain frequently calculated
509 * quantities by using shifts and masks in place of divisions
510 * modulos and multiplications.
511 */
512 #define blkoff(fs, loc) /* calculates (loc % fs->fs_bsize) */ \
513 ((loc) & (fs)->fs_qbmask)
514 #define fragoff(fs, loc) /* calculates (loc % fs->fs_fsize) */ \
515 ((loc) & (fs)->fs_qfmask)
516 #define lblktosize(fs, blk) /* calculates ((off_t)blk * fs->fs_bsize) */ \
517 ((off_t)(blk) << (fs)->fs_bshift)
518 #define lblkno(fs, loc) /* calculates (loc / fs->fs_bsize) */ \
519 ((loc) >> (fs)->fs_bshift)
520 #define numfrags(fs, loc) /* calculates (loc / fs->fs_fsize) */ \
521 ((loc) >> (fs)->fs_fshift)
522 #define blkroundup(fs, size) /* calculates roundup(size, fs->fs_bsize) */ \
523 (((size) + (fs)->fs_qbmask) & (fs)->fs_bmask)
524 #define fragroundup(fs, size) /* calculates roundup(size, fs->fs_fsize) */ \
525 (((size) + (fs)->fs_qfmask) & (fs)->fs_fmask)
526 #define fragstoblks(fs, frags) /* calculates (frags / fs->fs_frag) */ \
527 ((frags) >> (fs)->fs_fragshift)
528 #define blkstofrags(fs, blks) /* calculates (blks * fs->fs_frag) */ \
529 ((blks) << (fs)->fs_fragshift)
530 #define fragnum(fs, fsb) /* calculates (fsb % fs->fs_frag) */ \
531 ((fsb) & ((fs)->fs_frag - 1))
532 #define blknum(fs, fsb) /* calculates rounddown(fsb, fs->fs_frag) */ \
533 ((fsb) &~ ((fs)->fs_frag - 1))
534
535 /*
536 * Determine the number of available frags given a
537 * percentage to hold in reserve.
538 */
539 #define freespace(fs, percentreserved) \
540 (blkstofrags((fs), (fs)->fs_cstotal.cs_nbfree) + \
541 (fs)->fs_cstotal.cs_nffree - ((fs)->fs_dsize * (percentreserved) / 100))
542
543 /*
544 * Determining the size of a file block in the file system.
545 */
546 #define blksize(fs, ip, lbn) \
547 (((lbn) >= NDADDR || DIP((ip), size) >= ((lbn) + 1) << (fs)->fs_bshift) \
548 ? (fs)->fs_bsize \
549 : (fragroundup(fs, blkoff(fs, DIP((ip), size)))))
550 #define dblksize(fs, dip, lbn) \
551 (((lbn) >= NDADDR || (dip)->di_size >= ((lbn) + 1) << (fs)->fs_bshift) \
552 ? (fs)->fs_bsize \
553 : (fragroundup(fs, blkoff(fs, (dip)->di_size))))
554
555 #define sblksize(fs, size, lbn) \
556 (((lbn) >= NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \
557 ? (fs)->fs_bsize \
558 : (fragroundup(fs, blkoff(fs, (size)))))
559
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 /* Number of inodes per file system block (fs->fs_bsize) */
569 #define INOPB(fs) ((fs)->fs_inopb)
570 /* Number of inodes per file system fragment (fs->fs_fsize) */
571 #define INOPF(fs) ((fs)->fs_inopb >> (fs)->fs_fragshift)
572
573 /*
574 * Number of indirects in a file system block.
575 */
576 #define NINDIR(fs) ((fs)->fs_nindir)
577
578 extern const int inside[], around[];
579 extern const u_char *fragtbl[];