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 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * @(#)fs.h 8.13 (Berkeley) 3/21/95
|
30 * $FreeBSD: head/sys/ufs/ffs/fs.h 134011 2004-08-19 11:09:13Z jhb $
|
| 30 * $FreeBSD: head/sys/ufs/ffs/fs.h 136336 2004-10-09 20:16:06Z njl $ |
31 */
32
33#ifndef _UFS_FFS_FS_H_
34#define _UFS_FFS_FS_H_
35
36/*
37 * Each disk drive contains some number of filesystems.
38 * A filesystem consists of a number of cylinder groups.
39 * Each cylinder group has inodes and data.
40 *
41 * A filesystem is described by its super-block, which in turn
42 * describes the cylinder groups. The super-block is critical
43 * data and is replicated in each cylinder group to protect against
44 * catastrophic loss. This is done at `newfs' time and the critical
45 * super-block data does not change, so the copies need not be
46 * referenced further unless disaster strikes.
47 *
48 * For filesystem fs, the offsets of the various blocks of interest
49 * are given in the super block as:
50 * [fs->fs_sblkno] Super-block
51 * [fs->fs_cblkno] Cylinder group block
52 * [fs->fs_iblkno] Inode blocks
53 * [fs->fs_dblkno] Data blocks
54 * The beginning of cylinder group cg in fs, is given by
55 * the ``cgbase(fs, cg)'' macro.
56 *
57 * Depending on the architecture and the media, the superblock may
58 * reside in any one of four places. For tiny media where every block
59 * counts, it is placed at the very front of the partition. Historically,
60 * UFS1 placed it 8K from the front to leave room for the disk label and
61 * a small bootstrap. For UFS2 it got moved to 64K from the front to leave
62 * room for the disk label and a bigger bootstrap, and for really piggy
63 * systems we check at 256K from the front if the first three fail. In
64 * all cases the size of the superblock will be SBLOCKSIZE. All values are
65 * given in byte-offset form, so they do not imply a sector size. The
66 * SBLOCKSEARCH specifies the order in which the locations should be searched.
67 */
68#define SBLOCK_FLOPPY 0
69#define SBLOCK_UFS1 8192
70#define SBLOCK_UFS2 65536
71#define SBLOCK_PIGGY 262144
72#define SBLOCKSIZE 8192
73#define SBLOCKSEARCH \
74 { SBLOCK_UFS2, SBLOCK_UFS1, SBLOCK_FLOPPY, SBLOCK_PIGGY, -1 }
75
76/*
77 * Max number of fragments per block. This value is NOT tweakable.
78 */
79#define MAXFRAG 8
80
81/*
82 * Addresses stored in inodes are capable of addressing fragments
83 * of `blocks'. File system blocks of at most size MAXBSIZE can
84 * be optionally broken into 2, 4, or 8 pieces, each of which is
85 * addressable; these pieces may be DEV_BSIZE, or some multiple of
86 * a DEV_BSIZE unit.
87 *
88 * Large files consist of exclusively large data blocks. To avoid
89 * undue wasted disk space, the last data block of a small file may be
90 * allocated as only as many fragments of a large block as are
91 * necessary. The filesystem format retains only a single pointer
92 * to such a fragment, which is a piece of a single large block that
93 * has been divided. The size of such a fragment is determinable from
94 * information in the inode, using the ``blksize(fs, ip, lbn)'' macro.
95 *
96 * The filesystem records space availability at the fragment level;
97 * to determine block availability, aligned fragments are examined.
98 */
99
100/*
101 * MINBSIZE is the smallest allowable block size.
102 * In order to insure that it is possible to create files of size
103 * 2^32 with only two levels of indirection, MINBSIZE is set to 4096.
104 * MINBSIZE must be big enough to hold a cylinder group block,
105 * thus changes to (struct cg) must keep its size within MINBSIZE.
106 * Note that super blocks are always of size SBSIZE,
107 * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE.
108 */
109#define MINBSIZE 4096
110
111/*
112 * The path name on which the filesystem is mounted is maintained
113 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in
114 * the super block for this name.
115 */
116#define MAXMNTLEN 468
117
118/*
119 * The volume name for this filesystem is maintained in fs_volname.
120 * MAXVOLLEN defines the length of the buffer allocated.
121 */
122#define MAXVOLLEN 32
123
124/*
125 * There is a 128-byte region in the superblock reserved for in-core
126 * pointers to summary information. Originally this included an array
127 * of pointers to blocks of struct csum; now there are just a few
128 * pointers and the remaining space is padded with fs_ocsp[].
129 *
130 * NOCSPTRS determines the size of this padding. One pointer (fs_csp)
131 * is taken away to point to a contiguous array of struct csum for
132 * all cylinder groups; a second (fs_maxcluster) points to an array
133 * of cluster sizes that is computed as cylinder groups are inspected,
134 * and the third points to an array that tracks the creation of new
135 * directories. A fourth pointer, fs_active, is used when creating
136 * snapshots; it points to a bitmap of cylinder groups for which the
137 * free-block bitmap has changed since the snapshot operation began.
138 */
139#define NOCSPTRS ((128 / sizeof(void *)) - 4)
140
141/*
142 * A summary of contiguous blocks of various sizes is maintained
143 * in each cylinder group. Normally this is set by the initial
144 * value of fs_maxcontig. To conserve space, a maximum summary size
145 * is set by FS_MAXCONTIG.
146 */
147#define FS_MAXCONTIG 16
148
149/*
150 * MINFREE gives the minimum acceptable percentage of filesystem
151 * blocks which may be free. If the freelist drops below this level
152 * only the superuser may continue to allocate blocks. This may
153 * be set to 0 if no reserve of free blocks is deemed necessary,
154 * however throughput drops by fifty percent if the filesystem
155 * is run at between 95% and 100% full; thus the minimum default
156 * value of fs_minfree is 5%. However, to get good clustering
157 * performance, 10% is a better choice. hence we use 10% as our
158 * default value. With 10% free space, fragmentation is not a
159 * problem, so we choose to optimize for time.
160 */
161#define MINFREE 8
162#define DEFAULTOPT FS_OPTTIME
163
164/*
165 * Grigoriy Orlov <gluk@ptci.ru> has done some extensive work to fine
166 * tune the layout preferences for directories within a filesystem.
167 * His algorithm can be tuned by adjusting the following parameters
168 * which tell the system the average file size and the average number
169 * of files per directory. These defaults are well selected for typical
170 * filesystems, but may need to be tuned for odd cases like filesystems
171 * being used for squid caches or news spools.
172 */
173#define AVFILESIZ 16384 /* expected average file size */
174#define AFPDIR 64 /* expected number of files per directory */
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 ((ufs2_daddr_t)(1))
198#define BLK_SNAP ((ufs2_daddr_t)(2))
199
200/*
201 * Sysctl values for the fast filesystem.
202 */
203#define FFS_ADJ_REFCNT 1 /* adjust inode reference count */
204#define FFS_ADJ_BLKCNT 2 /* adjust inode used block count */
205#define FFS_BLK_FREE 3 /* free range of blocks in map */
206#define FFS_DIR_FREE 4 /* free specified dir inodes in map */
207#define FFS_FILE_FREE 5 /* free specified file inodes in map */
208#define FFS_SET_FLAGS 6 /* set filesystem flags */
209#define FFS_MAXID 7 /* number of valid ffs ids */
210
211/*
212 * Command structure passed in to the filesystem to adjust filesystem values.
213 */
214#define FFS_CMD_VERSION 0x19790518 /* version ID */
215struct fsck_cmd {
216 int32_t version; /* version of command structure */
217 int32_t handle; /* reference to filesystem to be changed */
218 int64_t value; /* inode or block number to be affected */
219 int64_t size; /* amount or range to be adjusted */
220 int64_t spare; /* reserved for future use */
221};
222
223/*
224 * Per cylinder group information; summarized in blocks allocated
225 * from first cylinder group data blocks. These blocks have to be
226 * read in from fs_csaddr (size fs_cssize) in addition to the
227 * super block.
228 */
229struct csum {
230 int32_t cs_ndir; /* number of directories */
231 int32_t cs_nbfree; /* number of free blocks */
232 int32_t cs_nifree; /* number of free inodes */
233 int32_t cs_nffree; /* number of free frags */
234};
235struct csum_total {
236 int64_t cs_ndir; /* number of directories */
237 int64_t cs_nbfree; /* number of free blocks */
238 int64_t cs_nifree; /* number of free inodes */
239 int64_t cs_nffree; /* number of free frags */
240 int64_t cs_numclusters; /* number of free clusters */
241 int64_t cs_spare[3]; /* future expansion */
242};
243
244/*
245 * Super block for an FFS filesystem.
246 */
247struct fs {
248 int32_t fs_firstfield; /* historic filesystem linked list, */
249 int32_t fs_unused_1; /* used for incore super blocks */
250 int32_t fs_sblkno; /* offset of super-block in filesys */
251 int32_t fs_cblkno; /* offset of cyl-block in filesys */
252 int32_t fs_iblkno; /* offset of inode-blocks in filesys */
253 int32_t fs_dblkno; /* offset of first data after cg */
254 int32_t fs_old_cgoffset; /* cylinder group offset in cylinder */
255 int32_t fs_old_cgmask; /* used to calc mod fs_ntrak */
256 int32_t fs_old_time; /* last time written */
257 int32_t fs_old_size; /* number of blocks in fs */
258 int32_t fs_old_dsize; /* number of data blocks in fs */
259 int32_t fs_ncg; /* number of cylinder groups */
260 int32_t fs_bsize; /* size of basic blocks in fs */
261 int32_t fs_fsize; /* size of frag blocks in fs */
262 int32_t fs_frag; /* number of frags in a block in fs */
263/* these are configuration parameters */
264 int32_t fs_minfree; /* minimum percentage of free blocks */
265 int32_t fs_old_rotdelay; /* num of ms for optimal next block */
266 int32_t fs_old_rps; /* disk revolutions per second */
267/* these fields can be computed from the others */
268 int32_t fs_bmask; /* ``blkoff'' calc of blk offsets */
269 int32_t fs_fmask; /* ``fragoff'' calc of frag offsets */
270 int32_t fs_bshift; /* ``lblkno'' calc of logical blkno */
271 int32_t fs_fshift; /* ``numfrags'' calc number of frags */
272/* these are configuration parameters */
273 int32_t fs_maxcontig; /* max number of contiguous blks */
274 int32_t fs_maxbpg; /* max number of blks per cyl group */
275/* these fields can be computed from the others */
276 int32_t fs_fragshift; /* block to frag shift */
277 int32_t fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */
278 int32_t fs_sbsize; /* actual size of super block */
279 int32_t fs_spare1[2]; /* old fs_csmask */
280 /* old fs_csshift */
281 int32_t fs_nindir; /* value of NINDIR */
282 int32_t fs_inopb; /* value of INOPB */
283 int32_t fs_old_nspf; /* value of NSPF */
284/* yet another configuration parameter */
285 int32_t fs_optim; /* optimization preference, see below */
286 int32_t fs_old_npsect; /* # sectors/track including spares */
287 int32_t fs_old_interleave; /* hardware sector interleave */
288 int32_t fs_old_trackskew; /* sector 0 skew, per track */
289 int32_t fs_id[2]; /* unique filesystem id */
290/* sizes determined by number of cylinder groups and their sizes */
291 int32_t fs_old_csaddr; /* blk addr of cyl grp summary area */
292 int32_t fs_cssize; /* size of cyl grp summary area */
293 int32_t fs_cgsize; /* cylinder group size */
294 int32_t fs_spare2; /* old fs_ntrak */
295 int32_t fs_old_nsect; /* sectors per track */
296 int32_t fs_old_spc; /* sectors per cylinder */
297 int32_t fs_old_ncyl; /* cylinders in filesystem */
298 int32_t fs_old_cpg; /* cylinders per group */
299 int32_t fs_ipg; /* inodes per group */
300 int32_t fs_fpg; /* blocks per group * fs_frag */
301/* this data must be re-computed after crashes */
302 struct csum fs_old_cstotal; /* cylinder summary information */
303/* these fields are cleared at mount time */
304 int8_t fs_fmod; /* super block modified flag */
305 int8_t fs_clean; /* filesystem is clean flag */
306 int8_t fs_ronly; /* mounted read-only flag */
307 int8_t fs_old_flags; /* old FS_ flags */
308 u_char fs_fsmnt[MAXMNTLEN]; /* name mounted on */
309 u_char fs_volname[MAXVOLLEN]; /* volume name */
310 u_int64_t fs_swuid; /* system-wide uid */
311 int32_t fs_pad; /* due to alignment of fs_swuid */
312/* these fields retain the current block allocation info */
313 int32_t fs_cgrotor; /* last cg searched */
314 void *fs_ocsp[NOCSPTRS]; /* padding; was list of fs_cs buffers */
315 u_int8_t *fs_contigdirs; /* # of contiguously allocated dirs */
316 struct csum *fs_csp; /* cg summary info buffer for fs_cs */
317 int32_t *fs_maxcluster; /* max cluster in each cyl group */
318 u_int *fs_active; /* used by snapshots to track fs */
319 int32_t fs_old_cpc; /* cyl per cycle in postbl */
320 int32_t fs_maxbsize; /* maximum blocking factor permitted */
321 int64_t fs_sparecon64[17]; /* old rotation block list head */
322 int64_t fs_sblockloc; /* byte offset of standard superblock */
323 struct csum_total fs_cstotal; /* cylinder summary information */
324 ufs_time_t fs_time; /* last time written */
325 int64_t fs_size; /* number of blocks in fs */
326 int64_t fs_dsize; /* number of data blocks in fs */
327 ufs2_daddr_t fs_csaddr; /* blk addr of cyl grp summary area */
328 int64_t fs_pendingblocks; /* blocks in process of being freed */
329 int32_t fs_pendinginodes; /* inodes in process of being freed */
330 int32_t fs_snapinum[FSMAXSNAP];/* list of snapshot inode numbers */
331 int32_t fs_avgfilesize; /* expected average file size */
332 int32_t fs_avgfpdir; /* expected # of files per directory */
333 int32_t fs_save_cgsize; /* save real cg size to use fs_bsize */
334 int32_t fs_sparecon32[26]; /* reserved for future constants */
335 int32_t fs_flags; /* see FS_ flags below */
336 int32_t fs_contigsumsize; /* size of cluster summary array */
337 int32_t fs_maxsymlinklen; /* max length of an internal symlink */
338 int32_t fs_old_inodefmt; /* format of on-disk inodes */
339 u_int64_t fs_maxfilesize; /* maximum representable file size */
340 int64_t fs_qbmask; /* ~fs_bmask for use with 64-bit size */
341 int64_t fs_qfmask; /* ~fs_fmask for use with 64-bit size */
342 int32_t fs_state; /* validate fs_clean field */
343 int32_t fs_old_postblformat; /* format of positional layout tables */
344 int32_t fs_old_nrpos; /* number of rotational positions */
345 int32_t fs_spare5[2]; /* old fs_postbloff */
346 /* old fs_rotbloff */
347 int32_t fs_magic; /* magic number */
348};
349
350/* Sanity checking. */
351#ifdef CTASSERT
352CTASSERT(sizeof(struct fs) == 1376);
353#endif
354
355/*
356 * Filesystem identification
357 */
358#define FS_UFS1_MAGIC 0x011954 /* UFS1 fast filesystem magic number */
359#define FS_UFS2_MAGIC 0x19540119 /* UFS2 fast filesystem magic number */
360#define FS_BAD_MAGIC 0x19960408 /* UFS incomplete newfs magic number */
361#define FS_OKAY 0x7c269d38 /* superblock checksum */
362#define FS_42INODEFMT -1 /* 4.2BSD inode format */
363#define FS_44INODEFMT 2 /* 4.4BSD inode format */
364
365/*
366 * Preference for optimization.
367 */
368#define FS_OPTTIME 0 /* minimize allocation time */
369#define FS_OPTSPACE 1 /* minimize disk fragmentation */
370
371/*
372 * Filesystem flags.
373 *
374 * The FS_UNCLEAN flag is set by the kernel when the filesystem was
375 * mounted with fs_clean set to zero. The FS_DOSOFTDEP flag indicates
376 * that the filesystem should be managed by the soft updates code.
377 * Note that the FS_NEEDSFSCK flag is set and cleared only by the
378 * fsck utility. It is set when background fsck finds an unexpected
379 * inconsistency which requires a traditional foreground fsck to be
380 * run. Such inconsistencies should only be found after an uncorrectable
381 * disk error. A foreground fsck will clear the FS_NEEDSFSCK flag when
382 * it has successfully cleaned up the filesystem. The kernel uses this
383 * flag to enforce that inconsistent filesystems be mounted read-only.
384 * The FS_INDEXDIRS flag when set indicates that the kernel maintains
385 * on-disk auxiliary indexes (such as B-trees) for speeding directory
386 * accesses. Kernels that do not support auxiliary indicies clear the
387 * flag to indicate that the indicies need to be rebuilt (by fsck) before
388 * they can be used.
389 *
390 * FS_ACLS indicates that ACLs are administratively enabled for the
391 * file system, so they should be loaded from extended attributes,
392 * observed for access control purposes, and be administered by object
393 * owners. FS_MULTILABEL indicates that the TrustedBSD MAC Framework
394 * should attempt to back MAC labels into extended attributes on the
395 * file system rather than maintain a single mount label for all
396 * objects.
397 */
398#define FS_UNCLEAN 0x01 /* filesystem not clean at mount */
399#define FS_DOSOFTDEP 0x02 /* filesystem using soft dependencies */
400#define FS_NEEDSFSCK 0x04 /* filesystem needs sync fsck before mount */
401#define FS_INDEXDIRS 0x08 /* kernel supports indexed directories */
402#define FS_ACLS 0x10 /* file system has ACLs enabled */
403#define FS_MULTILABEL 0x20 /* file system is MAC multi-label */
404#define FS_FLAGS_UPDATED 0x80 /* flags have been moved to new location */
405
406/*
407 * Macros to access bits in the fs_active array.
408 */
409#define ACTIVECGNUM(fs, cg) ((fs)->fs_active[(cg) / (NBBY * sizeof(int))])
410#define ACTIVECGOFF(cg) (1 << ((cg) % (NBBY * sizeof(int))))
411
412/*
413 * The size of a cylinder group is calculated by CGSIZE. The maximum size
414 * is limited by the fact that cylinder groups are at most one block.
415 * Its size is derived from the size of the maps maintained in the
416 * cylinder group and the (struct cg) size.
417 */
418#define CGSIZE(fs) \
419 /* base cg */ (sizeof(struct cg) + sizeof(int32_t) + \
420 /* old btotoff */ (fs)->fs_old_cpg * sizeof(int32_t) + \
421 /* old boff */ (fs)->fs_old_cpg * sizeof(u_int16_t) + \
422 /* inode map */ howmany((fs)->fs_ipg, NBBY) + \
423 /* block map */ howmany((fs)->fs_fpg, NBBY) +\
424 /* if present */ ((fs)->fs_contigsumsize <= 0 ? 0 : \
425 /* cluster sum */ (fs)->fs_contigsumsize * sizeof(int32_t) + \
426 /* cluster map */ howmany(fragstoblks(fs, (fs)->fs_fpg), NBBY)))
427
428/*
429 * The minimal number of cylinder groups that should be created.
430 */
431#define MINCYLGRPS 4
432
433/*
434 * Convert cylinder group to base address of its global summary info.
435 */
436#define fs_cs(fs, indx) fs_csp[indx]
437
438/*
439 * Cylinder group block for a filesystem.
440 */
441#define CG_MAGIC 0x090255
442struct cg {
443 int32_t cg_firstfield; /* historic cyl groups linked list */
444 int32_t cg_magic; /* magic number */
445 int32_t cg_old_time; /* time last written */
446 int32_t cg_cgx; /* we are the cgx'th cylinder group */
447 int16_t cg_old_ncyl; /* number of cyl's this cg */
448 int16_t cg_old_niblk; /* number of inode blocks this cg */
449 int32_t cg_ndblk; /* number of data blocks this cg */
450 struct csum cg_cs; /* cylinder summary information */
451 int32_t cg_rotor; /* position of last used block */
452 int32_t cg_frotor; /* position of last used frag */
453 int32_t cg_irotor; /* position of last used inode */
454 int32_t cg_frsum[MAXFRAG]; /* counts of available frags */
455 int32_t cg_old_btotoff; /* (int32) block totals per cylinder */
456 int32_t cg_old_boff; /* (u_int16) free block positions */
457 int32_t cg_iusedoff; /* (u_int8) used inode map */
458 int32_t cg_freeoff; /* (u_int8) free block map */
459 int32_t cg_nextfreeoff; /* (u_int8) next available space */
460 int32_t cg_clustersumoff; /* (u_int32) counts of avail clusters */
461 int32_t cg_clusteroff; /* (u_int8) free cluster map */
462 int32_t cg_nclusterblks; /* number of clusters this cg */
463 int32_t cg_niblk; /* number of inode blocks this cg */
464 int32_t cg_initediblk; /* last initialized inode */
465 int32_t cg_sparecon32[3]; /* reserved for future use */
466 ufs_time_t cg_time; /* time last written */
467 int64_t cg_sparecon64[3]; /* reserved for future use */
468 u_int8_t cg_space[1]; /* space for cylinder group maps */
469/* actually longer */
470};
471
472/*
473 * Macros for access to cylinder group array structures
474 */
475#define cg_chkmagic(cgp) ((cgp)->cg_magic == CG_MAGIC)
476#define cg_inosused(cgp) \
477 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_iusedoff))
478#define cg_blksfree(cgp) \
479 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_freeoff))
480#define cg_clustersfree(cgp) \
481 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_clusteroff))
482#define cg_clustersum(cgp) \
483 ((int32_t *)((uintptr_t)(cgp) + (cgp)->cg_clustersumoff))
484
485/*
486 * Turn filesystem block numbers into disk block addresses.
487 * This maps filesystem blocks to device size blocks.
488 */
|
489#define fsbtodb(fs, b) ((b) << (fs)->fs_fsbtodb)
|
| 489#define fsbtodb(fs, b) ((daddr_t)(b) << (fs)->fs_fsbtodb) |
490#define dbtofsb(fs, b) ((b) >> (fs)->fs_fsbtodb)
491
492/*
493 * Cylinder group macros to locate things in cylinder groups.
494 * They calc filesystem addresses of cylinder group data structures.
495 */
496#define cgbase(fs, c) (((ufs2_daddr_t)(fs)->fs_fpg) * (c))
497#define cgdmin(fs, c) (cgstart(fs, c) + (fs)->fs_dblkno) /* 1st data */
498#define cgimin(fs, c) (cgstart(fs, c) + (fs)->fs_iblkno) /* inode blk */
499#define cgsblock(fs, c) (cgstart(fs, c) + (fs)->fs_sblkno) /* super blk */
500#define cgtod(fs, c) (cgstart(fs, c) + (fs)->fs_cblkno) /* cg block */
501#define cgstart(fs, c) \
502 ((fs)->fs_magic == FS_UFS2_MAGIC ? cgbase(fs, c) : \
503 (cgbase(fs, c) + (fs)->fs_old_cgoffset * ((c) & ~((fs)->fs_old_cgmask))))
504
505/*
506 * Macros for handling inode numbers:
507 * inode number to filesystem block offset.
508 * inode number to cylinder group number.
509 * inode number to filesystem block address.
510 */
511#define ino_to_cg(fs, x) ((x) / (fs)->fs_ipg)
512#define ino_to_fsba(fs, x) \
513 ((ufs2_daddr_t)(cgimin(fs, ino_to_cg(fs, x)) + \
514 (blkstofrags((fs), (((x) % (fs)->fs_ipg) / INOPB(fs))))))
515#define ino_to_fsbo(fs, x) ((x) % INOPB(fs))
516
517/*
518 * Give cylinder group number for a filesystem block.
519 * Give cylinder group block number for a filesystem block.
520 */
521#define dtog(fs, d) ((d) / (fs)->fs_fpg)
522#define dtogd(fs, d) ((d) % (fs)->fs_fpg)
523
524/*
525 * Extract the bits for a block from a map.
526 * Compute the cylinder and rotational position of a cyl block addr.
527 */
528#define blkmap(fs, map, loc) \
529 (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag)))
530
531/*
532 * The following macros optimize certain frequently calculated
533 * quantities by using shifts and masks in place of divisions
534 * modulos and multiplications.
535 */
536#define blkoff(fs, loc) /* calculates (loc % fs->fs_bsize) */ \
537 ((loc) & (fs)->fs_qbmask)
538#define fragoff(fs, loc) /* calculates (loc % fs->fs_fsize) */ \
539 ((loc) & (fs)->fs_qfmask)
540#define lfragtosize(fs, frag) /* calculates ((off_t)frag * fs->fs_fsize) */ \
541 (((off_t)(frag)) << (fs)->fs_fshift)
542#define lblktosize(fs, blk) /* calculates ((off_t)blk * fs->fs_bsize) */ \
543 (((off_t)(blk)) << (fs)->fs_bshift)
544/* Use this only when `blk' is known to be small, e.g., < NDADDR. */
545#define smalllblktosize(fs, blk) /* calculates (blk * fs->fs_bsize) */ \
546 ((blk) << (fs)->fs_bshift)
547#define lblkno(fs, loc) /* calculates (loc / fs->fs_bsize) */ \
548 ((loc) >> (fs)->fs_bshift)
549#define numfrags(fs, loc) /* calculates (loc / fs->fs_fsize) */ \
550 ((loc) >> (fs)->fs_fshift)
551#define blkroundup(fs, size) /* calculates roundup(size, fs->fs_bsize) */ \
552 (((size) + (fs)->fs_qbmask) & (fs)->fs_bmask)
553#define fragroundup(fs, size) /* calculates roundup(size, fs->fs_fsize) */ \
554 (((size) + (fs)->fs_qfmask) & (fs)->fs_fmask)
555#define fragstoblks(fs, frags) /* calculates (frags / fs->fs_frag) */ \
556 ((frags) >> (fs)->fs_fragshift)
557#define blkstofrags(fs, blks) /* calculates (blks * fs->fs_frag) */ \
558 ((blks) << (fs)->fs_fragshift)
559#define fragnum(fs, fsb) /* calculates (fsb % fs->fs_frag) */ \
560 ((fsb) & ((fs)->fs_frag - 1))
561#define blknum(fs, fsb) /* calculates rounddown(fsb, fs->fs_frag) */ \
562 ((fsb) &~ ((fs)->fs_frag - 1))
563
564/*
565 * Determine the number of available frags given a
566 * percentage to hold in reserve.
567 */
568#define freespace(fs, percentreserved) \
569 (blkstofrags((fs), (fs)->fs_cstotal.cs_nbfree) + \
570 (fs)->fs_cstotal.cs_nffree - \
571 (((off_t)((fs)->fs_dsize)) * (percentreserved) / 100))
572
573/*
574 * Determining the size of a file block in the filesystem.
575 */
576#define blksize(fs, ip, lbn) \
577 (((lbn) >= NDADDR || (ip)->i_size >= smalllblktosize(fs, (lbn) + 1)) \
578 ? (fs)->fs_bsize \
579 : (fragroundup(fs, blkoff(fs, (ip)->i_size))))
580#define sblksize(fs, size, lbn) \
581 (((lbn) >= NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \
582 ? (fs)->fs_bsize \
583 : (fragroundup(fs, blkoff(fs, (size)))))
584
585
586/*
587 * Number of inodes in a secondary storage block/fragment.
588 */
589#define INOPB(fs) ((fs)->fs_inopb)
590#define INOPF(fs) ((fs)->fs_inopb >> (fs)->fs_fragshift)
591
592/*
593 * Number of indirects in a filesystem block.
594 */
595#define NINDIR(fs) ((fs)->fs_nindir)
596
597extern int inside[], around[];
598extern u_char *fragtbl[];
599
600#endif
|