FreeBSD/Linux Kernel Cross Reference
sys/ufs/ffs/fs.h
1 /* $NetBSD: fs.h,v 1.46 2005/12/11 12:25:25 christos Exp $ */
2
3 /*
4 * Copyright (c) 1982, 1986, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)fs.h 8.13 (Berkeley) 3/21/95
32 */
33
34 #ifndef _UFS_FFS_FS_H_
35 #define _UFS_FFS_FS_H_
36
37 /*
38 * Each disk drive contains some number of file systems.
39 * A file system consists of a number of cylinder groups.
40 * Each cylinder group has inodes and data.
41 *
42 * A file system is described by its super-block, which in turn
43 * describes the cylinder groups. The super-block is critical
44 * data and is replicated in each cylinder group to protect against
45 * catastrophic loss. This is done at `newfs' time and the critical
46 * super-block data does not change, so the copies need not be
47 * referenced further unless disaster strikes.
48 *
49 * For file system fs, the offsets of the various blocks of interest
50 * are given in the super block as:
51 * [fs->fs_sblkno] Super-block
52 * [fs->fs_cblkno] Cylinder group block
53 * [fs->fs_iblkno] Inode blocks
54 * [fs->fs_dblkno] Data blocks
55 * The beginning of cylinder group cg in fs, is given by
56 * the ``cgbase(fs, cg)'' macro.
57 *
58 * Depending on the architecture and the media, the superblock may
59 * reside in any one of four places. For tiny media where every block
60 * counts, it is placed at the very front of the partition. Historically,
61 * UFS1 placed it 8K from the front to leave room for the disk label and
62 * a small bootstrap. For UFS2 it got moved to 64K from the front to leave
63 * room for the disk label and a bigger bootstrap, and for really piggy
64 * systems we check at 256K from the front if the first three fail. In
65 * all cases the size of the superblock will be SBLOCKSIZE. All values are
66 * given in byte-offset form, so they do not imply a sector size. The
67 * SBLOCKSEARCH specifies the order in which the locations should be searched.
68 *
69 * Unfortunately the UFS2/FFSv2 change was done without adequate consideration
70 * of backward compatibility. In particular 'newfs' for a FFSv2 partition
71 * must overwrite any old FFSv1 superblock at 8k, and preferrably as many
72 * of the alternates as it can find - otherwise attempting to mount on a
73 * system that only supports FFSv1 is likely to succeed!.
74 * For a small FFSv1 filesystem, an old FFSv2 superblock can be left on
75 * the disk, and a system that tries to find an FFSv2 filesystem in preference
76 * to and FFSv1 one (as NetBSD does) can mount the old FFSv2 filesystem.
77 * As a added bonus, the 'first alternate' superblock of a FFSv1 filesystem
78 * with 64k blocks is at 64k - just where the code looks first when playing
79 * 'hunt the superblock'.
80 *
81 * The ffsv2 superblock layout (which might contain an ffsv1 filesystem)
82 * can be detected by checking for sb->fs_old_flags & FS_FLAGS_UPDATED.
83 * This is the default suberblock type for NetBSD since ffsv2 support was added.
84 */
85 #define BBSIZE 8192
86 #define BBOFF ((off_t)(0))
87 #define BBLOCK ((daddr_t)(0))
88
89 #define SBLOCK_FLOPPY 0
90 #define SBLOCK_UFS1 8192
91 #define SBLOCK_UFS2 65536
92 #define SBLOCK_PIGGY 262144
93 #define SBLOCKSIZE 8192
94 /*
95 * NB: Do not, under any circumstances, look for an ffsv1 filesystem at
96 * SBLOCK_UFS2. Doing so will find the wrong superblock for filesystems
97 * with a 64k block size.
98 */
99 #define SBLOCKSEARCH \
100 { SBLOCK_UFS2, SBLOCK_UFS1, SBLOCK_FLOPPY, SBLOCK_PIGGY, -1 }
101
102 /*
103 * Max number of fragments per block. This value is NOT tweakable.
104 */
105 #define MAXFRAG 8
106
107
108
109 /*
110 * Addresses stored in inodes are capable of addressing fragments
111 * of `blocks'. File system blocks of at most size MAXBSIZE can
112 * be optionally broken into 2, 4, or 8 pieces, each of which is
113 * addressable; these pieces may be DEV_BSIZE, or some multiple of
114 * a DEV_BSIZE unit.
115 *
116 * Large files consist of exclusively large data blocks. To avoid
117 * undue wasted disk space, the last data block of a small file may be
118 * allocated as only as many fragments of a large block as are
119 * necessary. The file system format retains only a single pointer
120 * to such a fragment, which is a piece of a single large block that
121 * has been divided. The size of such a fragment is determinable from
122 * information in the inode, using the ``blksize(fs, ip, lbn)'' macro.
123 *
124 * The file system records space availability at the fragment level;
125 * to determine block availability, aligned fragments are examined.
126 */
127
128 /*
129 * MINBSIZE is the smallest allowable block size.
130 * In order to insure that it is possible to create files of size
131 * 2^32 with only two levels of indirection, MINBSIZE is set to 4096.
132 * MINBSIZE must be big enough to hold a cylinder group block,
133 * thus changes to (struct cg) must keep its size within MINBSIZE.
134 * Note that super blocks are always of size SBSIZE,
135 * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE.
136 */
137 #define MINBSIZE 4096
138
139 /*
140 * The path name on which the file system is mounted is maintained
141 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in
142 * the super block for this name.
143 */
144 #define MAXMNTLEN 468
145
146 /*
147 * The volume name for this filesystem is maintained in fs_volname.
148 * MAXVOLLEN defines the length of the buffer allocated.
149 * This space used to be part of of fs_fsmnt.
150 */
151 #define MAXVOLLEN 32
152
153 /*
154 * There is a 128-byte region in the superblock reserved for in-core
155 * pointers to summary information. Originally this included an array
156 * of pointers to blocks of struct csum; now there are just four
157 * pointers and the remaining space is padded with fs_ocsp[].
158 * NOCSPTRS determines the size of this padding. One pointer (fs_csp)
159 * is taken away to point to a contiguous array of struct csum for
160 * all cylinder groups; a second (fs_maxcluster) points to an array
161 * of cluster sizes that is computed as cylinder groups are inspected;
162 * the third (fs_contigdirs) points to an array that tracks the
163 * creation of new directories; and the fourth (fs_active) is used
164 * by snapshots.
165 */
166 #define NOCSPTRS ((128 / sizeof(void *)) - 4)
167
168 /*
169 * A summary of contiguous blocks of various sizes is maintained
170 * in each cylinder group. Normally this is set by the initial
171 * value of fs_maxcontig. To conserve space, a maximum summary size
172 * is set by FS_MAXCONTIG.
173 */
174 #define FS_MAXCONTIG 16
175
176 /*
177 * The maximum number of snapshot nodes that can be associated
178 * with each filesystem. This limit affects only the number of
179 * snapshot files that can be recorded within the superblock so
180 * that they can be found when the filesystem is mounted. However,
181 * maintaining too many will slow the filesystem performance, so
182 * having this limit is a good idea.
183 */
184 #define FSMAXSNAP 20
185
186 /*
187 * Used to identify special blocks in snapshots:
188 *
189 * BLK_NOCOPY - A block that was unallocated at the time the snapshot
190 * was taken, hence does not need to be copied when written.
191 * BLK_SNAP - A block held by another snapshot that is not needed by this
192 * snapshot. When the other snapshot is freed, the BLK_SNAP entries
193 * are converted to BLK_NOCOPY. These are needed to allow fsck to
194 * identify blocks that are in use by other snapshots (which are
195 * expunged from this snapshot).
196 */
197 #define BLK_NOCOPY ((daddr_t)(1))
198 #define BLK_SNAP ((daddr_t)(2))
199
200 /*
201 * MINFREE gives the minimum acceptable percentage of file system
202 * blocks which may be free. If the freelist drops below this level
203 * only the superuser may continue to allocate blocks. This may
204 * be set to 0 if no reserve of free blocks is deemed necessary,
205 * however throughput drops by fifty percent if the file system
206 * is run at between 95% and 100% full; thus the minimum default
207 * value of fs_minfree is 5%. However, to get good clustering
208 * performance, 10% is a better choice. hence we use 10% as our
209 * default value. With 10% free space, fragmentation is not a
210 * problem, so we choose to optimize for time.
211 */
212 #define MINFREE 5
213 #define DEFAULTOPT FS_OPTTIME
214
215 /*
216 * Grigoriy Orlov <gluk@ptci.ru> has done some extensive work to fine
217 * tune the layout preferences for directories within a filesystem.
218 * His algorithm can be tuned by adjusting the following parameters
219 * which tell the system the average file size and the average number
220 * of files per directory. These defaults are well selected for typical
221 * filesystems, but may need to be tuned for odd cases like filesystems
222 * being used for squid caches or news spools.
223 */
224 #define AVFILESIZ 16384 /* expected average file size */
225 #define AFPDIR 64 /* expected number of files per directory */
226
227 /*
228 * Per cylinder group information; summarized in blocks allocated
229 * from first cylinder group data blocks. These blocks have to be
230 * read in from fs_csaddr (size fs_cssize) in addition to the
231 * super block.
232 */
233 struct csum {
234 int32_t cs_ndir; /* number of directories */
235 int32_t cs_nbfree; /* number of free blocks */
236 int32_t cs_nifree; /* number of free inodes */
237 int32_t cs_nffree; /* number of free frags */
238 };
239
240 struct csum_total {
241 int64_t cs_ndir; /* number of directories */
242 int64_t cs_nbfree; /* number of free blocks */
243 int64_t cs_nifree; /* number of free inodes */
244 int64_t cs_nffree; /* number of free frags */
245 int64_t cs_spare[4]; /* future expansion */
246 };
247
248
249 /*
250 * Super block for an FFS file system in memory.
251 */
252 struct fs {
253 int32_t fs_firstfield; /* historic file system linked list, */
254 int32_t fs_unused_1; /* used for incore super blocks */
255 int32_t fs_sblkno; /* addr of super-block in filesys */
256 int32_t fs_cblkno; /* offset of cyl-block in filesys */
257 int32_t fs_iblkno; /* offset of inode-blocks in filesys */
258 int32_t fs_dblkno; /* offset of first data after cg */
259 int32_t fs_old_cgoffset; /* cylinder group offset in cylinder */
260 int32_t fs_old_cgmask; /* used to calc mod fs_ntrak */
261 int32_t fs_old_time; /* last time written */
262 int32_t fs_old_size; /* number of blocks in fs */
263 int32_t fs_old_dsize; /* number of data blocks in fs */
264 int32_t fs_ncg; /* number of cylinder groups */
265 int32_t fs_bsize; /* size of basic blocks in fs */
266 int32_t fs_fsize; /* size of frag blocks in fs */
267 int32_t fs_frag; /* number of frags in a block in fs */
268 /* these are configuration parameters */
269 int32_t fs_minfree; /* minimum percentage of free blocks */
270 int32_t fs_old_rotdelay; /* num of ms for optimal next block */
271 int32_t fs_old_rps; /* disk revolutions per second */
272 /* these fields can be computed from the others */
273 int32_t fs_bmask; /* ``blkoff'' calc of blk offsets */
274 int32_t fs_fmask; /* ``fragoff'' calc of frag offsets */
275 int32_t fs_bshift; /* ``lblkno'' calc of logical blkno */
276 int32_t fs_fshift; /* ``numfrags'' calc number of frags */
277 /* these are configuration parameters */
278 int32_t fs_maxcontig; /* max number of contiguous blks */
279 int32_t fs_maxbpg; /* max number of blks per cyl group */
280 /* these fields can be computed from the others */
281 int32_t fs_fragshift; /* block to frag shift */
282 int32_t fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */
283 int32_t fs_sbsize; /* actual size of super block */
284 int32_t fs_spare1[2]; /* old fs_csmask */
285 /* old fs_csshift */
286 int32_t fs_nindir; /* value of NINDIR */
287 int32_t fs_inopb; /* value of INOPB */
288 int32_t fs_old_nspf; /* value of NSPF */
289 /* yet another configuration parameter */
290 int32_t fs_optim; /* optimization preference, see below */
291 /* these fields are derived from the hardware */
292 int32_t fs_old_npsect; /* # sectors/track including spares */
293 int32_t fs_old_interleave; /* hardware sector interleave */
294 int32_t fs_old_trackskew; /* sector 0 skew, per track */
295 /* fs_id takes the space of the unused fs_headswitch and fs_trkseek fields */
296 int32_t fs_id[2]; /* unique file system id */
297 /* sizes determined by number of cylinder groups and their sizes */
298 int32_t fs_old_csaddr; /* blk addr of cyl grp summary area */
299 int32_t fs_cssize; /* size of cyl grp summary area */
300 int32_t fs_cgsize; /* cylinder group size */
301 /* these fields are derived from the hardware */
302 int32_t fs_spare2; /* old fs_ntrak */
303 int32_t fs_old_nsect; /* sectors per track */
304 int32_t fs_old_spc; /* sectors per cylinder */
305 int32_t fs_old_ncyl; /* cylinders in file system */
306 int32_t fs_old_cpg; /* cylinders per group */
307 int32_t fs_ipg; /* inodes per group */
308 int32_t fs_fpg; /* blocks per group * fs_frag */
309 /* this data must be re-computed after crashes */
310 struct csum fs_old_cstotal; /* cylinder summary information */
311 /* these fields are cleared at mount time */
312 int8_t fs_fmod; /* super block modified flag */
313 int8_t fs_clean; /* file system is clean flag */
314 int8_t fs_ronly; /* mounted read-only flag */
315 uint8_t fs_old_flags; /* see FS_ flags below */
316 u_char fs_fsmnt[MAXMNTLEN]; /* name mounted on */
317 u_char fs_volname[MAXVOLLEN]; /* volume name */
318 uint64_t fs_swuid; /* system-wide uid */
319 int32_t fs_pad;
320 /* these fields retain the current block allocation info */
321 int32_t fs_cgrotor; /* last cg searched (UNUSED) */
322 void *fs_ocsp[NOCSPTRS]; /* padding; was list of fs_cs buffers */
323 u_int8_t *fs_contigdirs; /* # of contiguously allocated dirs */
324 struct csum *fs_csp; /* cg summary info buffer for fs_cs */
325 int32_t *fs_maxcluster; /* max cluster in each cyl group */
326 u_char *fs_active; /* used by snapshots to track fs */
327 int32_t fs_old_cpc; /* cyl per cycle in postbl */
328 /* this area is otherwise allocated unless fs_old_flags & FS_FLAGS_UPDATED */
329 int32_t fs_maxbsize; /* maximum blocking factor permitted */
330 int64_t fs_sparecon64[17]; /* old rotation block list head */
331 int64_t fs_sblockloc; /* byte offset of standard superblock */
332 struct csum_total fs_cstotal; /* cylinder summary information */
333 int64_t fs_time; /* last time written */
334 int64_t fs_size; /* number of blocks in fs */
335 int64_t fs_dsize; /* number of data blocks in fs */
336 int64_t fs_csaddr; /* blk addr of cyl grp summary area */
337 int64_t fs_pendingblocks; /* blocks in process of being freed */
338 int32_t fs_pendinginodes; /* inodes in process of being freed */
339 int32_t fs_snapinum[FSMAXSNAP];/* list of snapshot inode numbers */
340 /* back to stuff that has been around a while */
341 int32_t fs_avgfilesize; /* expected average file size */
342 int32_t fs_avgfpdir; /* expected # of files per directory */
343 int32_t fs_save_cgsize; /* save real cg size to use fs_bsize */
344 int32_t fs_sparecon32[26]; /* reserved for future constants */
345 uint32_t fs_flags; /* see FS_ flags below */
346 /* back to stuff that has been around a while (again) */
347 int32_t fs_contigsumsize; /* size of cluster summary array */
348 int32_t fs_maxsymlinklen; /* max length of an internal symlink */
349 int32_t fs_old_inodefmt; /* format of on-disk inodes */
350 u_int64_t fs_maxfilesize; /* maximum representable file size */
351 int64_t fs_qbmask; /* ~fs_bmask for use with 64-bit size */
352 int64_t fs_qfmask; /* ~fs_fmask for use with 64-bit size */
353 int32_t fs_state; /* validate fs_clean field (UNUSED) */
354 int32_t fs_old_postblformat; /* format of positional layout tables */
355 int32_t fs_old_nrpos; /* number of rotational positions */
356 int32_t fs_spare5[2]; /* old fs_postbloff */
357 /* old fs_rotbloff */
358 int32_t fs_magic; /* magic number */
359 };
360
361 #define fs_old_postbloff fs_spare5[0]
362 #define fs_old_rotbloff fs_spare5[1]
363 #define fs_old_postbl_start fs_maxbsize
364 #define fs_old_headswitch fs_id[0]
365 #define fs_old_trkseek fs_id[1]
366 #define fs_old_csmask fs_spare1[0]
367 #define fs_old_csshift fs_spare1[1]
368
369 #define FS_42POSTBLFMT -1 /* 4.2BSD rotational table format */
370 #define FS_DYNAMICPOSTBLFMT 1 /* dynamic rotational table format */
371
372 #define old_fs_postbl(fs_, cylno, opostblsave) \
373 ((((fs_)->fs_old_postblformat == FS_42POSTBLFMT) || \
374 ((fs_)->fs_old_postbloff == offsetof(struct fs, fs_old_postbl_start))) \
375 ? ((int16_t *)(opostblsave) + (cylno) * (fs_)->fs_old_nrpos) \
376 : ((int16_t *)((uint8_t *)(fs_) + \
377 (fs_)->fs_old_postbloff) + (cylno) * (fs_)->fs_old_nrpos))
378 #define old_fs_rotbl(fs) \
379 (((fs)->fs_old_postblformat == FS_42POSTBLFMT) \
380 ? ((uint8_t *)(&(fs)->fs_magic+1)) \
381 : ((uint8_t *)((uint8_t *)(fs) + (fs)->fs_old_rotbloff)))
382
383 /*
384 * File system identification
385 */
386 #define FS_UFS1_MAGIC 0x011954 /* UFS1 fast file system magic number */
387 #define FS_UFS2_MAGIC 0x19540119 /* UFS2 fast file system magic number */
388 #define FS_UFS1_MAGIC_SWAPPED 0x54190100
389 #define FS_UFS2_MAGIC_SWAPPED 0x19015419
390 #define FS_OKAY 0x7c269d38 /* superblock checksum */
391 #define FS_42INODEFMT -1 /* 4.2BSD inode format */
392 #define FS_44INODEFMT 2 /* 4.4BSD inode format */
393
394 /*
395 * File system clean flags
396 */
397 #define FS_ISCLEAN 0x01
398 #define FS_WASCLEAN 0x02
399
400 /*
401 * Preference for optimization.
402 */
403 #define FS_OPTTIME 0 /* minimize allocation time */
404 #define FS_OPTSPACE 1 /* minimize disk fragmentation */
405
406 /*
407 * File system flags
408 */
409 #define FS_UNCLEAN 0x01 /* file system not clean at mount (unused) */
410 #define FS_DOSOFTDEP 0x02 /* file system using soft dependencies */
411 #define FS_NEEDSFSCK 0x04 /* needs sync fsck (FreeBSD compat, unused) */
412 #define FS_INDEXDIRS 0x08 /* kernel supports indexed directories */
413 #define FS_ACLS 0x10 /* file system has ACLs enabled */
414 #define FS_MULTILABEL 0x20 /* file system is MAC multi-label */
415 #define FS_FLAGS_UPDATED 0x80 /* flags have been moved to new location */
416
417 /*
418 * File system internal flags, also in fs_flags.
419 * (Pick highest number to avoid conflicts with others)
420 */
421 #define FS_SWAPPED 0x80000000 /* file system is endian swapped */
422 #define FS_INTERNAL 0x80000000 /* mask for internal flags */
423
424 /*
425 * Macros to access bits in the fs_active array.
426 */
427 #define ACTIVECG_SET(fs, cg) \
428 do { \
429 if ((fs)->fs_active != NULL) \
430 setbit((fs)->fs_active, (cg)); \
431 } while (/*CONSTCOND*/ 0)
432 #define ACTIVECG_CLR(fs, cg) \
433 do { \
434 if ((fs)->fs_active != NULL) \
435 clrbit((fs)->fs_active, (cg)); \
436 } while (/*CONSTCOND*/ 0)
437 #define ACTIVECG_ISSET(fs, cg) \
438 ((fs)->fs_active != NULL && isset((fs)->fs_active, (cg)))
439
440 /*
441 * The size of a cylinder group is calculated by CGSIZE. The maximum size
442 * is limited by the fact that cylinder groups are at most one block.
443 * Its size is derived from the size of the maps maintained in the
444 * cylinder group and the (struct cg) size.
445 */
446 #define CGSIZE_IF(fs, ipg, fpg) \
447 /* base cg */ (sizeof(struct cg) + sizeof(int32_t) + \
448 /* old btotoff */ (fs)->fs_old_cpg * sizeof(int32_t) + \
449 /* old boff */ (fs)->fs_old_cpg * sizeof(u_int16_t) + \
450 /* inode map */ howmany((ipg), NBBY) + \
451 /* block map */ howmany((fpg), NBBY) +\
452 /* if present */ ((fs)->fs_contigsumsize <= 0 ? 0 : \
453 /* cluster sum */ (fs)->fs_contigsumsize * sizeof(int32_t) + \
454 /* cluster map */ howmany(fragstoblks(fs, (fpg)), NBBY)))
455
456 #define CGSIZE(fs) CGSIZE_IF((fs), (fs)->fs_ipg, (fs)->fs_fpg)
457
458 /*
459 * The minimal number of cylinder groups that should be created.
460 */
461 #define MINCYLGRPS 4
462
463
464 /*
465 * Convert cylinder group to base address of its global summary info.
466 */
467 #define fs_cs(fs, indx) fs_csp[indx]
468
469 /*
470 * Cylinder group block for a file system.
471 */
472 #define CG_MAGIC 0x090255
473 struct cg {
474 int32_t cg_firstfield; /* historic cyl groups linked list */
475 int32_t cg_magic; /* magic number */
476 int32_t cg_old_time; /* time last written */
477 int32_t cg_cgx; /* we are the cgx'th cylinder group */
478 int16_t cg_old_ncyl; /* number of cyl's this cg */
479 int16_t cg_old_niblk; /* number of inode blocks this cg */
480 int32_t cg_ndblk; /* number of data blocks this cg */
481 struct csum cg_cs; /* cylinder summary information */
482 int32_t cg_rotor; /* position of last used block */
483 int32_t cg_frotor; /* position of last used frag */
484 int32_t cg_irotor; /* position of last used inode */
485 int32_t cg_frsum[MAXFRAG]; /* counts of available frags */
486 int32_t cg_old_btotoff; /* (int32) block totals per cylinder */
487 int32_t cg_old_boff; /* (u_int16) free block positions */
488 int32_t cg_iusedoff; /* (u_int8) used inode map */
489 int32_t cg_freeoff; /* (u_int8) free block map */
490 int32_t cg_nextfreeoff; /* (u_int8) next available space */
491 int32_t cg_clustersumoff; /* (u_int32) counts of avail clusters */
492 int32_t cg_clusteroff; /* (u_int8) free cluster map */
493 int32_t cg_nclusterblks; /* number of clusters this cg */
494 int32_t cg_niblk; /* number of inode blocks this cg */
495 int32_t cg_initediblk; /* last initialized inode */
496 int32_t cg_sparecon32[3]; /* reserved for future use */
497 int64_t cg_time; /* time last written */
498 int64_t cg_sparecon64[3]; /* reserved for future use */
499 u_int8_t cg_space[1]; /* space for cylinder group maps */
500 /* actually longer */
501 };
502
503 /*
504 * The following structure is defined
505 * for compatibility with old file systems.
506 */
507 struct ocg {
508 int32_t cg_firstfield; /* historic linked list of cyl groups */
509 int32_t cg_unused_1; /* used for incore cyl groups */
510 int32_t cg_time; /* time last written */
511 int32_t cg_cgx; /* we are the cgx'th cylinder group */
512 int16_t cg_ncyl; /* number of cyl's this cg */
513 int16_t cg_niblk; /* number of inode blocks this cg */
514 int32_t cg_ndblk; /* number of data blocks this cg */
515 struct csum cg_cs; /* cylinder summary information */
516 int32_t cg_rotor; /* position of last used block */
517 int32_t cg_frotor; /* position of last used frag */
518 int32_t cg_irotor; /* position of last used inode */
519 int32_t cg_frsum[8]; /* counts of available frags */
520 int32_t cg_btot[32]; /* block totals per cylinder */
521 int16_t cg_b[32][8]; /* positions of free blocks */
522 u_int8_t cg_iused[256]; /* used inode map */
523 int32_t cg_magic; /* magic number */
524 u_int8_t cg_free[1]; /* free block map */
525 /* actually longer */
526 };
527
528
529 /*
530 * Macros for access to cylinder group array structures.
531 */
532 #define old_cg_blktot_old(cgp, ns) \
533 (((struct ocg *)(cgp))->cg_btot)
534 #define old_cg_blks_old(fs, cgp, cylno, ns) \
535 (((struct ocg *)(cgp))->cg_b[cylno])
536
537 #define old_cg_blktot_new(cgp, ns) \
538 ((int32_t *)((u_int8_t *)(cgp) + \
539 ufs_rw32((cgp)->cg_old_btotoff, (ns))))
540 #define old_cg_blks_new(fs, cgp, cylno, ns) \
541 ((int16_t *)((u_int8_t *)(cgp) + \
542 ufs_rw32((cgp)->cg_old_boff, (ns))) + (cylno) * (fs)->fs_old_nrpos)
543
544 #define old_cg_blktot(cgp, ns) \
545 ((ufs_rw32((cgp)->cg_magic, (ns)) != CG_MAGIC) ? \
546 old_cg_blktot_old(cgp, ns) : old_cg_blktot_new(cgp, ns))
547 #define old_cg_blks(fs, cgp, cylno, ns) \
548 ((ufs_rw32((cgp)->cg_magic, (ns)) != CG_MAGIC) ? \
549 old_cg_blks_old(fs, cgp, cylno, ns) : old_cg_blks_new(fs, cgp, cylno, ns))
550
551 #define cg_inosused_new(cgp, ns) \
552 ((u_int8_t *)((u_int8_t *)(cgp) + \
553 ufs_rw32((cgp)->cg_iusedoff, (ns))))
554 #define cg_blksfree_new(cgp, ns) \
555 ((u_int8_t *)((u_int8_t *)(cgp) + \
556 ufs_rw32((cgp)->cg_freeoff, (ns))))
557 #define cg_chkmagic_new(cgp, ns) \
558 (ufs_rw32((cgp)->cg_magic, (ns)) == CG_MAGIC)
559
560 #define cg_inosused_old(cgp, ns) \
561 (((struct ocg *)(cgp))->cg_iused)
562 #define cg_blksfree_old(cgp, ns) \
563 (((struct ocg *)(cgp))->cg_free)
564 #define cg_chkmagic_old(cgp, ns) \
565 (ufs_rw32(((struct ocg *)(cgp))->cg_magic, (ns)) == CG_MAGIC)
566
567 #define cg_inosused(cgp, ns) \
568 ((ufs_rw32((cgp)->cg_magic, (ns)) != CG_MAGIC) ? \
569 cg_inosused_old(cgp, ns) : cg_inosused_new(cgp, ns))
570 #define cg_blksfree(cgp, ns) \
571 ((ufs_rw32((cgp)->cg_magic, (ns)) != CG_MAGIC) ? \
572 cg_blksfree_old(cgp, ns) : cg_blksfree_new(cgp, ns))
573 #define cg_chkmagic(cgp, ns) \
574 (cg_chkmagic_new(cgp, ns) || cg_chkmagic_old(cgp, ns))
575
576 #define cg_clustersfree(cgp, ns) \
577 ((u_int8_t *)((u_int8_t *)(cgp) + \
578 ufs_rw32((cgp)->cg_clusteroff, (ns))))
579 #define cg_clustersum(cgp, ns) \
580 ((int32_t *)((u_int8_t *)(cgp) + \
581 ufs_rw32((cgp)->cg_clustersumoff, (ns))))
582
583
584 /*
585 * Turn file system block numbers into disk block addresses.
586 * This maps file system blocks to device size blocks.
587 */
588 #define fsbtodb(fs, b) ((b) << (fs)->fs_fsbtodb)
589 #define dbtofsb(fs, b) ((b) >> (fs)->fs_fsbtodb)
590
591 /*
592 * Cylinder group macros to locate things in cylinder groups.
593 * They calc file system addresses of cylinder group data structures.
594 */
595 #define cgbase(fs, c) (((daddr_t)(fs)->fs_fpg) * (c))
596 #define cgstart_ufs1(fs, c) \
597 (cgbase(fs, c) + (fs)->fs_old_cgoffset * ((c) & ~((fs)->fs_old_cgmask)))
598 #define cgstart_ufs2(fs, c) cgbase((fs), (c))
599 #define cgstart(fs, c) ((fs)->fs_magic == FS_UFS2_MAGIC \
600 ? cgstart_ufs2((fs), (c)) : cgstart_ufs1((fs), (c)))
601 #define cgdmin(fs, c) (cgstart(fs, c) + (fs)->fs_dblkno) /* 1st data */
602 #define cgimin(fs, c) (cgstart(fs, c) + (fs)->fs_iblkno) /* inode blk */
603 #define cgsblock(fs, c) (cgstart(fs, c) + (fs)->fs_sblkno) /* super blk */
604 #define cgtod(fs, c) (cgstart(fs, c) + (fs)->fs_cblkno) /* cg block */
605
606 /*
607 * Macros for handling inode numbers:
608 * inode number to file system block offset.
609 * inode number to cylinder group number.
610 * inode number to file system block address.
611 */
612 #define ino_to_cg(fs, x) ((x) / (fs)->fs_ipg)
613 #define ino_to_fsba(fs, x) \
614 ((daddr_t)(cgimin(fs, ino_to_cg(fs, x)) + \
615 (blkstofrags((fs), (((x) % (fs)->fs_ipg) / INOPB(fs))))))
616 #define ino_to_fsbo(fs, x) ((x) % INOPB(fs))
617
618 /*
619 * Give cylinder group number for a file system block.
620 * Give cylinder group block number for a file system block.
621 */
622 #define dtog(fs, d) ((d) / (fs)->fs_fpg)
623 #define dtogd(fs, d) ((d) % (fs)->fs_fpg)
624
625 /*
626 * Extract the bits for a block from a map.
627 * Compute the cylinder and rotational position of a cyl block addr.
628 */
629 #define blkmap(fs, map, loc) \
630 (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag)))
631 #define old_cbtocylno(fs, bno) \
632 (fsbtodb(fs, bno) / (fs)->fs_old_spc)
633 #define old_cbtorpos(fs, bno) \
634 ((fs)->fs_old_nrpos <= 1 ? 0 : \
635 (fsbtodb(fs, bno) % (fs)->fs_old_spc / (fs)->fs_old_nsect * (fs)->fs_old_trackskew + \
636 fsbtodb(fs, bno) % (fs)->fs_old_spc % (fs)->fs_old_nsect * (fs)->fs_old_interleave) % \
637 (fs)->fs_old_nsect * (fs)->fs_old_nrpos / (fs)->fs_old_npsect)
638
639 /*
640 * The following macros optimize certain frequently calculated
641 * quantities by using shifts and masks in place of divisions
642 * modulos and multiplications.
643 */
644 #define blkoff(fs, loc) /* calculates (loc % fs->fs_bsize) */ \
645 ((loc) & (fs)->fs_qbmask)
646 #define fragoff(fs, loc) /* calculates (loc % fs->fs_fsize) */ \
647 ((loc) & (fs)->fs_qfmask)
648 #define lfragtosize(fs, frag) /* calculates ((off_t)frag * fs->fs_fsize) */ \
649 (((off_t)(frag)) << (fs)->fs_fshift)
650 #define lblktosize(fs, blk) /* calculates ((off_t)blk * fs->fs_bsize) */ \
651 (((off_t)(blk)) << (fs)->fs_bshift)
652 #define lblkno(fs, loc) /* calculates (loc / fs->fs_bsize) */ \
653 ((loc) >> (fs)->fs_bshift)
654 #define numfrags(fs, loc) /* calculates (loc / fs->fs_fsize) */ \
655 ((loc) >> (fs)->fs_fshift)
656 #define blkroundup(fs, size) /* calculates roundup(size, fs->fs_bsize) */ \
657 (((size) + (fs)->fs_qbmask) & (fs)->fs_bmask)
658 #define fragroundup(fs, size) /* calculates roundup(size, fs->fs_fsize) */ \
659 (((size) + (fs)->fs_qfmask) & (fs)->fs_fmask)
660 #define fragstoblks(fs, frags) /* calculates (frags / fs->fs_frag) */ \
661 ((frags) >> (fs)->fs_fragshift)
662 #define blkstofrags(fs, blks) /* calculates (blks * fs->fs_frag) */ \
663 ((blks) << (fs)->fs_fragshift)
664 #define fragnum(fs, fsb) /* calculates (fsb % fs->fs_frag) */ \
665 ((fsb) & ((fs)->fs_frag - 1))
666 #define blknum(fs, fsb) /* calculates rounddown(fsb, fs->fs_frag) */ \
667 ((fsb) &~ ((fs)->fs_frag - 1))
668
669 /*
670 * Determine the number of available frags given a
671 * percentage to hold in reserve.
672 */
673 #define freespace(fs, percentreserved) \
674 (blkstofrags((fs), (fs)->fs_cstotal.cs_nbfree) + \
675 (fs)->fs_cstotal.cs_nffree - \
676 (((off_t)((fs)->fs_dsize)) * (percentreserved) / 100))
677
678 /*
679 * Determining the size of a file block in the file system.
680 */
681 #define blksize(fs, ip, lbn) \
682 (((lbn) >= NDADDR || (ip)->i_size >= lblktosize(fs, (lbn) + 1)) \
683 ? (fs)->fs_bsize \
684 : (fragroundup(fs, blkoff(fs, (ip)->i_size))))
685
686 #define sblksize(fs, size, lbn) \
687 (((lbn) >= NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \
688 ? (fs)->fs_bsize \
689 : (fragroundup(fs, blkoff(fs, (size)))))
690
691
692 /*
693 * Number of inodes in a secondary storage block/fragment.
694 */
695 #define INOPB(fs) ((fs)->fs_inopb)
696 #define INOPF(fs) ((fs)->fs_inopb >> (fs)->fs_fragshift)
697
698 /*
699 * Number of indirects in a file system block.
700 */
701 #define NINDIR(fs) ((fs)->fs_nindir)
702
703 /*
704 * Apple UFS Label:
705 * We check for this to decide to use APPLEUFS_DIRBLKSIZ
706 */
707 #define APPLEUFS_LABEL_MAGIC 0x4c41424c /* LABL */
708 #define APPLEUFS_LABEL_SIZE 1024
709 #define APPLEUFS_LABEL_OFFSET (BBSIZE - APPLEUFS_LABEL_SIZE) /* located at 7k */
710 #define APPLEUFS_LABEL_VERSION 1
711 #define APPLEUFS_MAX_LABEL_NAME 512
712
713 struct appleufslabel {
714 u_int32_t ul_magic;
715 u_int16_t ul_checksum;
716 u_int16_t ul_unused0;
717 u_int32_t ul_version;
718 u_int32_t ul_time;
719 u_int16_t ul_namelen;
720 u_char ul_name[APPLEUFS_MAX_LABEL_NAME]; /* Warning: may not be null terminated */
721 u_int16_t ul_unused1;
722 u_int64_t ul_uuid; /* Note this is only 4 byte aligned */
723 u_char ul_reserved[24];
724 u_char ul_unused[460];
725 } __attribute__((__packed__));
726
727
728 #endif /* !_UFS_FFS_FS_H_ */
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