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: head/sys/ufs/ffs/fs.h 127818 2004-04-03 23:30:59Z mux $
35 */
36
37#ifndef _UFS_FFS_FS_H_
38#define _UFS_FFS_FS_H_
39
40/*
41 * Each disk drive contains some number of filesystems.
42 * A filesystem consists of a number of cylinder groups.
43 * Each cylinder group has inodes and data.
44 *
45 * A filesystem 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 filesystem 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 * Depending on the architecture and the media, the superblock may
62 * reside in any one of four places. For tiny media where every block
63 * counts, it is placed at the very front of the partition. Historically,
64 * UFS1 placed it 8K from the front to leave room for the disk label and
65 * a small bootstrap. For UFS2 it got moved to 64K from the front to leave
66 * room for the disk label and a bigger bootstrap, and for really piggy
67 * systems we check at 256K from the front if the first three fail. In
68 * all cases the size of the superblock will be SBLOCKSIZE. All values are
69 * given in byte-offset form, so they do not imply a sector size. The
70 * SBLOCKSEARCH specifies the order in which the locations should be searched.
71 */
72#define SBLOCK_FLOPPY 0
73#define SBLOCK_UFS1 8192
74#define SBLOCK_UFS2 65536
75#define SBLOCK_PIGGY 262144
76#define SBLOCKSIZE 8192
77#define SBLOCKSEARCH \
78 { SBLOCK_UFS2, SBLOCK_UFS1, SBLOCK_FLOPPY, SBLOCK_PIGGY, -1 }
79
80/*
81 * Max number of fragments per block. This value is NOT tweakable.
82 */
83#define MAXFRAG 8
84
85/*
86 * Addresses stored in inodes are capable of addressing fragments
87 * of `blocks'. File system blocks of at most size MAXBSIZE can
88 * be optionally broken into 2, 4, or 8 pieces, each of which is
89 * addressable; these pieces may be DEV_BSIZE, or some multiple of
90 * a DEV_BSIZE unit.
91 *
92 * Large files consist of exclusively large data blocks. To avoid
93 * undue wasted disk space, the last data block of a small file may be
94 * allocated as only as many fragments of a large block as are
95 * necessary. The filesystem format retains only a single pointer
96 * to such a fragment, which is a piece of a single large block that
97 * has been divided. The size of such a fragment is determinable from
98 * information in the inode, using the ``blksize(fs, ip, lbn)'' macro.
99 *
100 * The filesystem records space availability at the fragment level;
101 * to determine block availability, aligned fragments are examined.
102 */
103
104/*
105 * MINBSIZE is the smallest allowable block size.
106 * In order to insure that it is possible to create files of size
107 * 2^32 with only two levels of indirection, MINBSIZE is set to 4096.
108 * MINBSIZE must be big enough to hold a cylinder group block,
109 * thus changes to (struct cg) must keep its size within MINBSIZE.
110 * Note that super blocks are always of size SBSIZE,
111 * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE.
112 */
113#define MINBSIZE 4096
114
115/*
116 * The path name on which the filesystem is mounted is maintained
117 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in
118 * the super block for this name.
119 */
120#define MAXMNTLEN 468
121
122/*
123 * The volume name for this filesystem is maintained in fs_volname.
124 * MAXVOLLEN defines the length of the buffer allocated.
125 */
126#define MAXVOLLEN 32
127
128/*
129 * There is a 128-byte region in the superblock reserved for in-core
130 * pointers to summary information. Originally this included an array
131 * of pointers to blocks of struct csum; now there are just a few
132 * pointers and the remaining space is padded with fs_ocsp[].
133 *
134 * NOCSPTRS determines the size of this padding. One pointer (fs_csp)
135 * is taken away to point to a contiguous array of struct csum for
136 * all cylinder groups; a second (fs_maxcluster) points to an array
137 * of cluster sizes that is computed as cylinder groups are inspected,
138 * and the third points to an array that tracks the creation of new
139 * directories. A fourth pointer, fs_active, is used when creating
140 * snapshots; it points to a bitmap of cylinder groups for which the
141 * free-block bitmap has changed since the snapshot operation began.
142 */
143#define NOCSPTRS ((128 / sizeof(void *)) - 4)
144
145/*
146 * A summary of contiguous blocks of various sizes is maintained
147 * in each cylinder group. Normally this is set by the initial
148 * value of fs_maxcontig. To conserve space, a maximum summary size
149 * is set by FS_MAXCONTIG.
150 */
151#define FS_MAXCONTIG 16
152
153/*
154 * MINFREE gives the minimum acceptable percentage of filesystem
155 * blocks which may be free. If the freelist drops below this level
156 * only the superuser may continue to allocate blocks. This may
157 * be set to 0 if no reserve of free blocks is deemed necessary,
158 * however throughput drops by fifty percent if the filesystem
159 * is run at between 95% and 100% full; thus the minimum default
160 * value of fs_minfree is 5%. However, to get good clustering
161 * performance, 10% is a better choice. hence we use 10% as our
162 * default value. With 10% free space, fragmentation is not a
163 * problem, so we choose to optimize for time.
164 */
165#define MINFREE 8
166#define DEFAULTOPT FS_OPTTIME
167
168/*
169 * Grigoriy Orlov <gluk@ptci.ru> has done some extensive work to fine
170 * tune the layout preferences for directories within a filesystem.
171 * His algorithm can be tuned by adjusting the following parameters
172 * which tell the system the average file size and the average number
173 * of files per directory. These defaults are well selected for typical
174 * filesystems, but may need to be tuned for odd cases like filesystems
175 * being used for sqiud caches or news spools.
176 */
177#define AVFILESIZ 16384 /* expected average file size */
178#define AFPDIR 64 /* expected number of files per directory */
179
180/*
181 * The maximum number of snapshot nodes that can be associated
182 * with each filesystem. This limit affects only the number of
183 * snapshot files that can be recorded within the superblock so
184 * that they can be found when the filesystem is mounted. However,
185 * maintaining too many will slow the filesystem performance, so
186 * having this limit is a good idea.
187 */
188#define FSMAXSNAP 20
189
190/*
191 * Used to identify special blocks in snapshots:
192 *
193 * BLK_NOCOPY - A block that was unallocated at the time the snapshot
194 * was taken, hence does not need to be copied when written.
195 * BLK_SNAP - A block held by another snapshot that is not needed by this
196 * snapshot. When the other snapshot is freed, the BLK_SNAP entries
197 * are converted to BLK_NOCOPY. These are needed to allow fsck to
198 * identify blocks that are in use by other snapshots (which are
199 * expunged from this snapshot).
200 */
201#define BLK_NOCOPY ((ufs2_daddr_t)(1))
202#define BLK_SNAP ((ufs2_daddr_t)(2))
203
204/*
205 * Sysctl values for the fast filesystem.
206 */
207#define FFS_ADJ_REFCNT 1 /* adjust inode reference count */
208#define FFS_ADJ_BLKCNT 2 /* adjust inode used block count */
209#define FFS_BLK_FREE 3 /* free range of blocks in map */
210#define FFS_DIR_FREE 4 /* free specified dir inodes in map */
211#define FFS_FILE_FREE 5 /* free specified file inodes in map */
212#define FFS_SET_FLAGS 6 /* set filesystem flags */
213#define FFS_MAXID 7 /* number of valid ffs ids */
214
215/*
216 * Command structure passed in to the filesystem to adjust filesystem values.
217 */
218#define FFS_CMD_VERSION 0x19790518 /* version ID */
219struct fsck_cmd {
220 int32_t version; /* version of command structure */
221 int32_t handle; /* reference to filesystem to be changed */
222 int64_t value; /* inode or block number to be affected */
223 int64_t size; /* amount or range to be adjusted */
224 int64_t spare; /* reserved for future use */
225};
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 */
233struct 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};
239struct csum_total {
240 int64_t cs_ndir; /* number of directories */
241 int64_t cs_nbfree; /* number of free blocks */
242 int64_t cs_nifree; /* number of free inodes */
243 int64_t cs_nffree; /* number of free frags */
244 int64_t cs_numclusters; /* number of free clusters */
245 int64_t cs_spare[3]; /* future expansion */
246};
247
248/*
249 * Super block for an FFS filesystem.
250 */
251struct fs {
252 int32_t fs_firstfield; /* historic filesystem linked list, */
253 int32_t fs_unused_1; /* used for incore super blocks */
254 int32_t fs_sblkno; /* offset of super-block in filesys */
255 int32_t fs_cblkno; /* offset of cyl-block in filesys */
256 int32_t fs_iblkno; /* offset of inode-blocks in filesys */
257 int32_t fs_dblkno; /* offset of first data after cg */
258 int32_t fs_old_cgoffset; /* cylinder group offset in cylinder */
259 int32_t fs_old_cgmask; /* used to calc mod fs_ntrak */
260 int32_t fs_old_time; /* last time written */
261 int32_t fs_old_size; /* number of blocks in fs */
262 int32_t fs_old_dsize; /* number of data blocks in fs */
263 int32_t fs_ncg; /* number of cylinder groups */
264 int32_t fs_bsize; /* size of basic blocks in fs */
265 int32_t fs_fsize; /* size of frag blocks in fs */
266 int32_t fs_frag; /* number of frags in a block in fs */
267/* these are configuration parameters */
268 int32_t fs_minfree; /* minimum percentage of free blocks */
269 int32_t fs_old_rotdelay; /* num of ms for optimal next block */
270 int32_t fs_old_rps; /* disk revolutions per second */
271/* these fields can be computed from the others */
272 int32_t fs_bmask; /* ``blkoff'' calc of blk offsets */
273 int32_t fs_fmask; /* ``fragoff'' calc of frag offsets */
274 int32_t fs_bshift; /* ``lblkno'' calc of logical blkno */
275 int32_t fs_fshift; /* ``numfrags'' calc number of frags */
276/* these are configuration parameters */
277 int32_t fs_maxcontig; /* max number of contiguous blks */
278 int32_t fs_maxbpg; /* max number of blks per cyl group */
279/* these fields can be computed from the others */
280 int32_t fs_fragshift; /* block to frag shift */
281 int32_t fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */
282 int32_t fs_sbsize; /* actual size of super block */
283 int32_t fs_spare1[2]; /* old fs_csmask */
284 /* old fs_csshift */
285 int32_t fs_nindir; /* value of NINDIR */
286 int32_t fs_inopb; /* value of INOPB */
287 int32_t fs_old_nspf; /* value of NSPF */
288/* yet another configuration parameter */
289 int32_t fs_optim; /* optimization preference, see below */
290 int32_t fs_old_npsect; /* # sectors/track including spares */
291 int32_t fs_old_interleave; /* hardware sector interleave */
292 int32_t fs_old_trackskew; /* sector 0 skew, per track */
293 int32_t fs_id[2]; /* unique filesystem id */
294/* sizes determined by number of cylinder groups and their sizes */
295 int32_t fs_old_csaddr; /* blk addr of cyl grp summary area */
296 int32_t fs_cssize; /* size of cyl grp summary area */
297 int32_t fs_cgsize; /* cylinder group size */
298 int32_t fs_spare2; /* old fs_ntrak */
299 int32_t fs_old_nsect; /* sectors per track */
300 int32_t fs_old_spc; /* sectors per cylinder */
301 int32_t fs_old_ncyl; /* cylinders in filesystem */
302 int32_t fs_old_cpg; /* cylinders per group */
303 int32_t fs_ipg; /* inodes per group */
304 int32_t fs_fpg; /* blocks per group * fs_frag */
305/* this data must be re-computed after crashes */
306 struct csum fs_old_cstotal; /* cylinder summary information */
307/* these fields are cleared at mount time */
308 int8_t fs_fmod; /* super block modified flag */
309 int8_t fs_clean; /* filesystem is clean flag */
310 int8_t fs_ronly; /* mounted read-only flag */
311 int8_t fs_old_flags; /* old FS_ flags */
312 u_char fs_fsmnt[MAXMNTLEN]; /* name mounted on */
313 u_char fs_volname[MAXVOLLEN]; /* volume name */
314 u_int64_t fs_swuid; /* system-wide uid */
315 int32_t fs_pad; /* due to alignment of fs_swuid */
316/* these fields retain the current block allocation info */
317 int32_t fs_cgrotor; /* last cg searched */
318 void *fs_ocsp[NOCSPTRS]; /* padding; was list of fs_cs buffers */
319 u_int8_t *fs_contigdirs; /* # of contiguously allocated dirs */
320 struct csum *fs_csp; /* cg summary info buffer for fs_cs */
321 int32_t *fs_maxcluster; /* max cluster in each cyl group */
322 u_int *fs_active; /* used by snapshots to track fs */
323 int32_t fs_old_cpc; /* cyl per cycle in postbl */
324 int32_t fs_maxbsize; /* maximum blocking factor permitted */
325 int64_t fs_sparecon64[17]; /* old rotation block list head */
326 int64_t fs_sblockloc; /* byte offset of standard superblock */
327 struct csum_total fs_cstotal; /* cylinder summary information */
328 ufs_time_t fs_time; /* last time written */
329 int64_t fs_size; /* number of blocks in fs */
330 int64_t fs_dsize; /* number of data blocks in fs */
331 ufs2_daddr_t fs_csaddr; /* blk addr of cyl grp summary area */
332 int64_t fs_pendingblocks; /* blocks in process of being freed */
333 int32_t fs_pendinginodes; /* inodes in process of being freed */
334 int32_t fs_snapinum[FSMAXSNAP];/* list of snapshot inode numbers */
335 int32_t fs_avgfilesize; /* expected average file size */
336 int32_t fs_avgfpdir; /* expected # of files per directory */
337 int32_t fs_save_cgsize; /* save real cg size to use fs_bsize */
338 int32_t fs_sparecon32[26]; /* reserved for future constants */
339 int32_t fs_flags; /* see FS_ flags below */
340 int32_t fs_contigsumsize; /* size of cluster summary array */
341 int32_t fs_maxsymlinklen; /* max length of an internal symlink */
342 int32_t fs_old_inodefmt; /* format of on-disk inodes */
343 u_int64_t fs_maxfilesize; /* maximum representable file size */
344 int64_t fs_qbmask; /* ~fs_bmask for use with 64-bit size */
345 int64_t fs_qfmask; /* ~fs_fmask for use with 64-bit size */
346 int32_t fs_state; /* validate fs_clean field */
347 int32_t fs_old_postblformat; /* format of positional layout tables */
348 int32_t fs_old_nrpos; /* number of rotational positions */
349 int32_t fs_spare5[2]; /* old fs_postbloff */
350 /* old fs_rotbloff */
351 int32_t fs_magic; /* magic number */
352};
353
354/* Sanity checking. */
355#ifdef CTASSERT
356CTASSERT(sizeof(struct fs) == 1376);
357#endif
358
359/*
360 * Filesystem identification
361 */
362#define FS_UFS1_MAGIC 0x011954 /* UFS1 fast filesystem magic number */
363#define FS_UFS2_MAGIC 0x19540119 /* UFS2 fast filesystem magic number */
364#define FS_BAD2_MAGIC 0x19960408 /* UFS2 incomplete newfs magic number */
365#define FS_OKAY 0x7c269d38 /* superblock checksum */
366#define FS_42INODEFMT -1 /* 4.2BSD inode format */
367#define FS_44INODEFMT 2 /* 4.4BSD inode format */
368
369/*
370 * Preference for optimization.
371 */
372#define FS_OPTTIME 0 /* minimize allocation time */
373#define FS_OPTSPACE 1 /* minimize disk fragmentation */
374
375/*
376 * Filesystem flags.
377 *
378 * The FS_UNCLEAN flag is set by the kernel when the filesystem was
379 * mounted with fs_clean set to zero. The FS_DOSOFTDEP flag indicates
380 * that the filesystem should be managed by the soft updates code.
381 * Note that the FS_NEEDSFSCK flag is set and cleared only by the
382 * fsck utility. It is set when background fsck finds an unexpected
383 * inconsistency which requires a traditional foreground fsck to be
384 * run. Such inconsistencies should only be found after an uncorrectable
385 * disk error. A foreground fsck will clear the FS_NEEDSFSCK flag when
386 * it has successfully cleaned up the filesystem. The kernel uses this
387 * flag to enforce that inconsistent filesystems be mounted read-only.
388 * The FS_INDEXDIRS flag when set indicates that the kernel maintains
389 * on-disk auxiliary indexes (such as B-trees) for speeding directory
390 * accesses. Kernels that do not support auxiliary indicies clear the
391 * flag to indicate that the indicies need to be rebuilt (by fsck) before
392 * they can be used.
393 *
394 * FS_ACLS indicates that ACLs are administratively enabled for the
395 * file system, so they should be loaded from extended attributes,
396 * observed for access control purposes, and be administered by object
397 * owners. FS_MULTILABEL indicates that the TrustedBSD MAC Framework
398 * should attempt to back MAC labels into extended attributes on the
399 * file system rather than maintain a single mount label for all
400 * objects.
401 */
402#define FS_UNCLEAN 0x01 /* filesystem not clean at mount */
403#define FS_DOSOFTDEP 0x02 /* filesystem using soft dependencies */
404#define FS_NEEDSFSCK 0x04 /* filesystem needs sync fsck before mount */
405#define FS_INDEXDIRS 0x08 /* kernel supports indexed directories */
406#define FS_ACLS 0x10 /* file system has ACLs enabled */
407#define FS_MULTILABEL 0x20 /* file system is MAC multi-label */
408#define FS_FLAGS_UPDATED 0x80 /* flags have been moved to new location */
409
410/*
411 * Macros to access bits in the fs_active array.
412 */
413#define ACTIVECGNUM(fs, cg) ((fs)->fs_active[(cg) / (NBBY * sizeof(int))])
414#define ACTIVECGOFF(cg) (1 << ((cg) % (NBBY * sizeof(int))))
415
416/*
417 * The size of a cylinder group is calculated by CGSIZE. The maximum size
418 * is limited by the fact that cylinder groups are at most one block.
419 * Its size is derived from the size of the maps maintained in the
420 * cylinder group and the (struct cg) size.
421 */
422#define CGSIZE(fs) \
423 /* base cg */ (sizeof(struct cg) + sizeof(int32_t) + \
424 /* old btotoff */ (fs)->fs_old_cpg * sizeof(int32_t) + \
425 /* old boff */ (fs)->fs_old_cpg * sizeof(u_int16_t) + \
426 /* inode map */ howmany((fs)->fs_ipg, NBBY) + \
427 /* block map */ howmany((fs)->fs_fpg, NBBY) +\
428 /* if present */ ((fs)->fs_contigsumsize <= 0 ? 0 : \
429 /* cluster sum */ (fs)->fs_contigsumsize * sizeof(int32_t) + \
430 /* cluster map */ howmany(fragstoblks(fs, (fs)->fs_fpg), NBBY)))
431
432/*
433 * The minimal number of cylinder groups that should be created.
434 */
435#define MINCYLGRPS 4
436
437/*
438 * Convert cylinder group to base address of its global summary info.
439 */
440#define fs_cs(fs, indx) fs_csp[indx]
441
442/*
443 * Cylinder group block for a filesystem.
444 */
445#define CG_MAGIC 0x090255
446struct cg {
447 int32_t cg_firstfield; /* historic cyl groups linked list */
448 int32_t cg_magic; /* magic number */
449 int32_t cg_old_time; /* time last written */
450 int32_t cg_cgx; /* we are the cgx'th cylinder group */
451 int16_t cg_old_ncyl; /* number of cyl's this cg */
452 int16_t cg_old_niblk; /* number of inode blocks this cg */
453 int32_t cg_ndblk; /* number of data blocks this cg */
454 struct csum cg_cs; /* cylinder summary information */
455 int32_t cg_rotor; /* position of last used block */
456 int32_t cg_frotor; /* position of last used frag */
457 int32_t cg_irotor; /* position of last used inode */
458 int32_t cg_frsum[MAXFRAG]; /* counts of available frags */
459 int32_t cg_old_btotoff; /* (int32) block totals per cylinder */
460 int32_t cg_old_boff; /* (u_int16) free block positions */
461 int32_t cg_iusedoff; /* (u_int8) used inode map */
462 int32_t cg_freeoff; /* (u_int8) free block map */
463 int32_t cg_nextfreeoff; /* (u_int8) next available space */
464 int32_t cg_clustersumoff; /* (u_int32) counts of avail clusters */
465 int32_t cg_clusteroff; /* (u_int8) free cluster map */
466 int32_t cg_nclusterblks; /* number of clusters this cg */
467 int32_t cg_niblk; /* number of inode blocks this cg */
468 int32_t cg_initediblk; /* last initialized inode */
469 int32_t cg_sparecon32[3]; /* reserved for future use */
470 ufs_time_t cg_time; /* time last written */
471 int64_t cg_sparecon64[3]; /* reserved for future use */
472 u_int8_t cg_space[1]; /* space for cylinder group maps */
473/* actually longer */
474};
475
476/*
477 * Macros for access to cylinder group array structures
478 */
479#define cg_chkmagic(cgp) ((cgp)->cg_magic == CG_MAGIC)
480#define cg_inosused(cgp) \
481 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_iusedoff))
482#define cg_blksfree(cgp) \
483 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_freeoff))
484#define cg_clustersfree(cgp) \
485 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_clusteroff))
486#define cg_clustersum(cgp) \
487 ((int32_t *)((uintptr_t)(cgp) + (cgp)->cg_clustersumoff))
488
489/*
490 * Turn filesystem block numbers into disk block addresses.
491 * This maps filesystem blocks to device size blocks.
492 */
493#define fsbtodb(fs, b) ((b) << (fs)->fs_fsbtodb)
494#define dbtofsb(fs, b) ((b) >> (fs)->fs_fsbtodb)
495
496/*
497 * Cylinder group macros to locate things in cylinder groups.
498 * They calc filesystem addresses of cylinder group data structures.
499 */
500#define cgbase(fs, c) (((ufs2_daddr_t)(fs)->fs_fpg) * (c))
501#define cgdmin(fs, c) (cgstart(fs, c) + (fs)->fs_dblkno) /* 1st data */
502#define cgimin(fs, c) (cgstart(fs, c) + (fs)->fs_iblkno) /* inode blk */
503#define cgsblock(fs, c) (cgstart(fs, c) + (fs)->fs_sblkno) /* super blk */
504#define cgtod(fs, c) (cgstart(fs, c) + (fs)->fs_cblkno) /* cg block */
505#define cgstart(fs, c) \
506 ((fs)->fs_magic == FS_UFS2_MAGIC ? cgbase(fs, c) : \
507 (cgbase(fs, c) + (fs)->fs_old_cgoffset * ((c) & ~((fs)->fs_old_cgmask))))
508
509/*
510 * Macros for handling inode numbers:
511 * inode number to filesystem block offset.
512 * inode number to cylinder group number.
513 * inode number to filesystem block address.
514 */
515#define ino_to_cg(fs, x) ((x) / (fs)->fs_ipg)
516#define ino_to_fsba(fs, x) \
517 ((ufs2_daddr_t)(cgimin(fs, ino_to_cg(fs, x)) + \
518 (blkstofrags((fs), (((x) % (fs)->fs_ipg) / INOPB(fs))))))
519#define ino_to_fsbo(fs, x) ((x) % INOPB(fs))
520
521/*
522 * Give cylinder group number for a filesystem block.
523 * Give cylinder group block number for a filesystem block.
524 */
525#define dtog(fs, d) ((d) / (fs)->fs_fpg)
526#define dtogd(fs, d) ((d) % (fs)->fs_fpg)
527
528/*
529 * Extract the bits for a block from a map.
530 * Compute the cylinder and rotational position of a cyl block addr.
531 */
532#define blkmap(fs, map, loc) \
533 (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag)))
534
535/*
536 * The following macros optimize certain frequently calculated
537 * quantities by using shifts and masks in place of divisions
538 * modulos and multiplications.
539 */
540#define blkoff(fs, loc) /* calculates (loc % fs->fs_bsize) */ \
541 ((loc) & (fs)->fs_qbmask)
542#define fragoff(fs, loc) /* calculates (loc % fs->fs_fsize) */ \
543 ((loc) & (fs)->fs_qfmask)
544#define lfragtosize(fs, frag) /* calculates ((off_t)frag * fs->fs_fsize) */ \
545 (((off_t)(frag)) << (fs)->fs_fshift)
546#define lblktosize(fs, blk) /* calculates ((off_t)blk * fs->fs_bsize) */ \
547 (((off_t)(blk)) << (fs)->fs_bshift)
548/* Use this only when `blk' is known to be small, e.g., < NDADDR. */
549#define smalllblktosize(fs, blk) /* calculates (blk * fs->fs_bsize) */ \
550 ((blk) << (fs)->fs_bshift)
551#define lblkno(fs, loc) /* calculates (loc / fs->fs_bsize) */ \
552 ((loc) >> (fs)->fs_bshift)
553#define numfrags(fs, loc) /* calculates (loc / fs->fs_fsize) */ \
554 ((loc) >> (fs)->fs_fshift)
555#define blkroundup(fs, size) /* calculates roundup(size, fs->fs_bsize) */ \
556 (((size) + (fs)->fs_qbmask) & (fs)->fs_bmask)
557#define fragroundup(fs, size) /* calculates roundup(size, fs->fs_fsize) */ \
558 (((size) + (fs)->fs_qfmask) & (fs)->fs_fmask)
559#define fragstoblks(fs, frags) /* calculates (frags / fs->fs_frag) */ \
560 ((frags) >> (fs)->fs_fragshift)
561#define blkstofrags(fs, blks) /* calculates (blks * fs->fs_frag) */ \
562 ((blks) << (fs)->fs_fragshift)
563#define fragnum(fs, fsb) /* calculates (fsb % fs->fs_frag) */ \
564 ((fsb) & ((fs)->fs_frag - 1))
565#define blknum(fs, fsb) /* calculates rounddown(fsb, fs->fs_frag) */ \
566 ((fsb) &~ ((fs)->fs_frag - 1))
567
568/*
569 * Determine the number of available frags given a
570 * percentage to hold in reserve.
571 */
572#define freespace(fs, percentreserved) \
573 (blkstofrags((fs), (fs)->fs_cstotal.cs_nbfree) + \
574 (fs)->fs_cstotal.cs_nffree - \
575 (((off_t)((fs)->fs_dsize)) * (percentreserved) / 100))
576
577/*
578 * Determining the size of a file block in the filesystem.
579 */
580#define blksize(fs, ip, lbn) \
581 (((lbn) >= NDADDR || (ip)->i_size >= smalllblktosize(fs, (lbn) + 1)) \
582 ? (fs)->fs_bsize \
583 : (fragroundup(fs, blkoff(fs, (ip)->i_size))))
584#define sblksize(fs, size, lbn) \
585 (((lbn) >= NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \
586 ? (fs)->fs_bsize \
587 : (fragroundup(fs, blkoff(fs, (size)))))
588
589
590/*
591 * Number of inodes in a secondary storage block/fragment.
592 */
593#define INOPB(fs) ((fs)->fs_inopb)
594#define INOPF(fs) ((fs)->fs_inopb >> (fs)->fs_fragshift)
595
596/*
597 * Number of indirects in a filesystem block.
598 */
599#define NINDIR(fs) ((fs)->fs_nindir)
600
601extern int inside[], around[];
602extern u_char *fragtbl[];
603
604#endif
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: head/sys/ufs/ffs/fs.h 127818 2004-04-03 23:30:59Z mux $
35 */
36
37#ifndef _UFS_FFS_FS_H_
38#define _UFS_FFS_FS_H_
39
40/*
41 * Each disk drive contains some number of filesystems.
42 * A filesystem consists of a number of cylinder groups.
43 * Each cylinder group has inodes and data.
44 *
45 * A filesystem 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 filesystem 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 * Depending on the architecture and the media, the superblock may
62 * reside in any one of four places. For tiny media where every block
63 * counts, it is placed at the very front of the partition. Historically,
64 * UFS1 placed it 8K from the front to leave room for the disk label and
65 * a small bootstrap. For UFS2 it got moved to 64K from the front to leave
66 * room for the disk label and a bigger bootstrap, and for really piggy
67 * systems we check at 256K from the front if the first three fail. In
68 * all cases the size of the superblock will be SBLOCKSIZE. All values are
69 * given in byte-offset form, so they do not imply a sector size. The
70 * SBLOCKSEARCH specifies the order in which the locations should be searched.
71 */
72#define SBLOCK_FLOPPY 0
73#define SBLOCK_UFS1 8192
74#define SBLOCK_UFS2 65536
75#define SBLOCK_PIGGY 262144
76#define SBLOCKSIZE 8192
77#define SBLOCKSEARCH \
78 { SBLOCK_UFS2, SBLOCK_UFS1, SBLOCK_FLOPPY, SBLOCK_PIGGY, -1 }
79
80/*
81 * Max number of fragments per block. This value is NOT tweakable.
82 */
83#define MAXFRAG 8
84
85/*
86 * Addresses stored in inodes are capable of addressing fragments
87 * of `blocks'. File system blocks of at most size MAXBSIZE can
88 * be optionally broken into 2, 4, or 8 pieces, each of which is
89 * addressable; these pieces may be DEV_BSIZE, or some multiple of
90 * a DEV_BSIZE unit.
91 *
92 * Large files consist of exclusively large data blocks. To avoid
93 * undue wasted disk space, the last data block of a small file may be
94 * allocated as only as many fragments of a large block as are
95 * necessary. The filesystem format retains only a single pointer
96 * to such a fragment, which is a piece of a single large block that
97 * has been divided. The size of such a fragment is determinable from
98 * information in the inode, using the ``blksize(fs, ip, lbn)'' macro.
99 *
100 * The filesystem records space availability at the fragment level;
101 * to determine block availability, aligned fragments are examined.
102 */
103
104/*
105 * MINBSIZE is the smallest allowable block size.
106 * In order to insure that it is possible to create files of size
107 * 2^32 with only two levels of indirection, MINBSIZE is set to 4096.
108 * MINBSIZE must be big enough to hold a cylinder group block,
109 * thus changes to (struct cg) must keep its size within MINBSIZE.
110 * Note that super blocks are always of size SBSIZE,
111 * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE.
112 */
113#define MINBSIZE 4096
114
115/*
116 * The path name on which the filesystem is mounted is maintained
117 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in
118 * the super block for this name.
119 */
120#define MAXMNTLEN 468
121
122/*
123 * The volume name for this filesystem is maintained in fs_volname.
124 * MAXVOLLEN defines the length of the buffer allocated.
125 */
126#define MAXVOLLEN 32
127
128/*
129 * There is a 128-byte region in the superblock reserved for in-core
130 * pointers to summary information. Originally this included an array
131 * of pointers to blocks of struct csum; now there are just a few
132 * pointers and the remaining space is padded with fs_ocsp[].
133 *
134 * NOCSPTRS determines the size of this padding. One pointer (fs_csp)
135 * is taken away to point to a contiguous array of struct csum for
136 * all cylinder groups; a second (fs_maxcluster) points to an array
137 * of cluster sizes that is computed as cylinder groups are inspected,
138 * and the third points to an array that tracks the creation of new
139 * directories. A fourth pointer, fs_active, is used when creating
140 * snapshots; it points to a bitmap of cylinder groups for which the
141 * free-block bitmap has changed since the snapshot operation began.
142 */
143#define NOCSPTRS ((128 / sizeof(void *)) - 4)
144
145/*
146 * A summary of contiguous blocks of various sizes is maintained
147 * in each cylinder group. Normally this is set by the initial
148 * value of fs_maxcontig. To conserve space, a maximum summary size
149 * is set by FS_MAXCONTIG.
150 */
151#define FS_MAXCONTIG 16
152
153/*
154 * MINFREE gives the minimum acceptable percentage of filesystem
155 * blocks which may be free. If the freelist drops below this level
156 * only the superuser may continue to allocate blocks. This may
157 * be set to 0 if no reserve of free blocks is deemed necessary,
158 * however throughput drops by fifty percent if the filesystem
159 * is run at between 95% and 100% full; thus the minimum default
160 * value of fs_minfree is 5%. However, to get good clustering
161 * performance, 10% is a better choice. hence we use 10% as our
162 * default value. With 10% free space, fragmentation is not a
163 * problem, so we choose to optimize for time.
164 */
165#define MINFREE 8
166#define DEFAULTOPT FS_OPTTIME
167
168/*
169 * Grigoriy Orlov <gluk@ptci.ru> has done some extensive work to fine
170 * tune the layout preferences for directories within a filesystem.
171 * His algorithm can be tuned by adjusting the following parameters
172 * which tell the system the average file size and the average number
173 * of files per directory. These defaults are well selected for typical
174 * filesystems, but may need to be tuned for odd cases like filesystems
175 * being used for sqiud caches or news spools.
176 */
177#define AVFILESIZ 16384 /* expected average file size */
178#define AFPDIR 64 /* expected number of files per directory */
179
180/*
181 * The maximum number of snapshot nodes that can be associated
182 * with each filesystem. This limit affects only the number of
183 * snapshot files that can be recorded within the superblock so
184 * that they can be found when the filesystem is mounted. However,
185 * maintaining too many will slow the filesystem performance, so
186 * having this limit is a good idea.
187 */
188#define FSMAXSNAP 20
189
190/*
191 * Used to identify special blocks in snapshots:
192 *
193 * BLK_NOCOPY - A block that was unallocated at the time the snapshot
194 * was taken, hence does not need to be copied when written.
195 * BLK_SNAP - A block held by another snapshot that is not needed by this
196 * snapshot. When the other snapshot is freed, the BLK_SNAP entries
197 * are converted to BLK_NOCOPY. These are needed to allow fsck to
198 * identify blocks that are in use by other snapshots (which are
199 * expunged from this snapshot).
200 */
201#define BLK_NOCOPY ((ufs2_daddr_t)(1))
202#define BLK_SNAP ((ufs2_daddr_t)(2))
203
204/*
205 * Sysctl values for the fast filesystem.
206 */
207#define FFS_ADJ_REFCNT 1 /* adjust inode reference count */
208#define FFS_ADJ_BLKCNT 2 /* adjust inode used block count */
209#define FFS_BLK_FREE 3 /* free range of blocks in map */
210#define FFS_DIR_FREE 4 /* free specified dir inodes in map */
211#define FFS_FILE_FREE 5 /* free specified file inodes in map */
212#define FFS_SET_FLAGS 6 /* set filesystem flags */
213#define FFS_MAXID 7 /* number of valid ffs ids */
214
215/*
216 * Command structure passed in to the filesystem to adjust filesystem values.
217 */
218#define FFS_CMD_VERSION 0x19790518 /* version ID */
219struct fsck_cmd {
220 int32_t version; /* version of command structure */
221 int32_t handle; /* reference to filesystem to be changed */
222 int64_t value; /* inode or block number to be affected */
223 int64_t size; /* amount or range to be adjusted */
224 int64_t spare; /* reserved for future use */
225};
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 */
233struct 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};
239struct csum_total {
240 int64_t cs_ndir; /* number of directories */
241 int64_t cs_nbfree; /* number of free blocks */
242 int64_t cs_nifree; /* number of free inodes */
243 int64_t cs_nffree; /* number of free frags */
244 int64_t cs_numclusters; /* number of free clusters */
245 int64_t cs_spare[3]; /* future expansion */
246};
247
248/*
249 * Super block for an FFS filesystem.
250 */
251struct fs {
252 int32_t fs_firstfield; /* historic filesystem linked list, */
253 int32_t fs_unused_1; /* used for incore super blocks */
254 int32_t fs_sblkno; /* offset of super-block in filesys */
255 int32_t fs_cblkno; /* offset of cyl-block in filesys */
256 int32_t fs_iblkno; /* offset of inode-blocks in filesys */
257 int32_t fs_dblkno; /* offset of first data after cg */
258 int32_t fs_old_cgoffset; /* cylinder group offset in cylinder */
259 int32_t fs_old_cgmask; /* used to calc mod fs_ntrak */
260 int32_t fs_old_time; /* last time written */
261 int32_t fs_old_size; /* number of blocks in fs */
262 int32_t fs_old_dsize; /* number of data blocks in fs */
263 int32_t fs_ncg; /* number of cylinder groups */
264 int32_t fs_bsize; /* size of basic blocks in fs */
265 int32_t fs_fsize; /* size of frag blocks in fs */
266 int32_t fs_frag; /* number of frags in a block in fs */
267/* these are configuration parameters */
268 int32_t fs_minfree; /* minimum percentage of free blocks */
269 int32_t fs_old_rotdelay; /* num of ms for optimal next block */
270 int32_t fs_old_rps; /* disk revolutions per second */
271/* these fields can be computed from the others */
272 int32_t fs_bmask; /* ``blkoff'' calc of blk offsets */
273 int32_t fs_fmask; /* ``fragoff'' calc of frag offsets */
274 int32_t fs_bshift; /* ``lblkno'' calc of logical blkno */
275 int32_t fs_fshift; /* ``numfrags'' calc number of frags */
276/* these are configuration parameters */
277 int32_t fs_maxcontig; /* max number of contiguous blks */
278 int32_t fs_maxbpg; /* max number of blks per cyl group */
279/* these fields can be computed from the others */
280 int32_t fs_fragshift; /* block to frag shift */
281 int32_t fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */
282 int32_t fs_sbsize; /* actual size of super block */
283 int32_t fs_spare1[2]; /* old fs_csmask */
284 /* old fs_csshift */
285 int32_t fs_nindir; /* value of NINDIR */
286 int32_t fs_inopb; /* value of INOPB */
287 int32_t fs_old_nspf; /* value of NSPF */
288/* yet another configuration parameter */
289 int32_t fs_optim; /* optimization preference, see below */
290 int32_t fs_old_npsect; /* # sectors/track including spares */
291 int32_t fs_old_interleave; /* hardware sector interleave */
292 int32_t fs_old_trackskew; /* sector 0 skew, per track */
293 int32_t fs_id[2]; /* unique filesystem id */
294/* sizes determined by number of cylinder groups and their sizes */
295 int32_t fs_old_csaddr; /* blk addr of cyl grp summary area */
296 int32_t fs_cssize; /* size of cyl grp summary area */
297 int32_t fs_cgsize; /* cylinder group size */
298 int32_t fs_spare2; /* old fs_ntrak */
299 int32_t fs_old_nsect; /* sectors per track */
300 int32_t fs_old_spc; /* sectors per cylinder */
301 int32_t fs_old_ncyl; /* cylinders in filesystem */
302 int32_t fs_old_cpg; /* cylinders per group */
303 int32_t fs_ipg; /* inodes per group */
304 int32_t fs_fpg; /* blocks per group * fs_frag */
305/* this data must be re-computed after crashes */
306 struct csum fs_old_cstotal; /* cylinder summary information */
307/* these fields are cleared at mount time */
308 int8_t fs_fmod; /* super block modified flag */
309 int8_t fs_clean; /* filesystem is clean flag */
310 int8_t fs_ronly; /* mounted read-only flag */
311 int8_t fs_old_flags; /* old FS_ flags */
312 u_char fs_fsmnt[MAXMNTLEN]; /* name mounted on */
313 u_char fs_volname[MAXVOLLEN]; /* volume name */
314 u_int64_t fs_swuid; /* system-wide uid */
315 int32_t fs_pad; /* due to alignment of fs_swuid */
316/* these fields retain the current block allocation info */
317 int32_t fs_cgrotor; /* last cg searched */
318 void *fs_ocsp[NOCSPTRS]; /* padding; was list of fs_cs buffers */
319 u_int8_t *fs_contigdirs; /* # of contiguously allocated dirs */
320 struct csum *fs_csp; /* cg summary info buffer for fs_cs */
321 int32_t *fs_maxcluster; /* max cluster in each cyl group */
322 u_int *fs_active; /* used by snapshots to track fs */
323 int32_t fs_old_cpc; /* cyl per cycle in postbl */
324 int32_t fs_maxbsize; /* maximum blocking factor permitted */
325 int64_t fs_sparecon64[17]; /* old rotation block list head */
326 int64_t fs_sblockloc; /* byte offset of standard superblock */
327 struct csum_total fs_cstotal; /* cylinder summary information */
328 ufs_time_t fs_time; /* last time written */
329 int64_t fs_size; /* number of blocks in fs */
330 int64_t fs_dsize; /* number of data blocks in fs */
331 ufs2_daddr_t fs_csaddr; /* blk addr of cyl grp summary area */
332 int64_t fs_pendingblocks; /* blocks in process of being freed */
333 int32_t fs_pendinginodes; /* inodes in process of being freed */
334 int32_t fs_snapinum[FSMAXSNAP];/* list of snapshot inode numbers */
335 int32_t fs_avgfilesize; /* expected average file size */
336 int32_t fs_avgfpdir; /* expected # of files per directory */
337 int32_t fs_save_cgsize; /* save real cg size to use fs_bsize */
338 int32_t fs_sparecon32[26]; /* reserved for future constants */
339 int32_t fs_flags; /* see FS_ flags below */
340 int32_t fs_contigsumsize; /* size of cluster summary array */
341 int32_t fs_maxsymlinklen; /* max length of an internal symlink */
342 int32_t fs_old_inodefmt; /* format of on-disk inodes */
343 u_int64_t fs_maxfilesize; /* maximum representable file size */
344 int64_t fs_qbmask; /* ~fs_bmask for use with 64-bit size */
345 int64_t fs_qfmask; /* ~fs_fmask for use with 64-bit size */
346 int32_t fs_state; /* validate fs_clean field */
347 int32_t fs_old_postblformat; /* format of positional layout tables */
348 int32_t fs_old_nrpos; /* number of rotational positions */
349 int32_t fs_spare5[2]; /* old fs_postbloff */
350 /* old fs_rotbloff */
351 int32_t fs_magic; /* magic number */
352};
353
354/* Sanity checking. */
355#ifdef CTASSERT
356CTASSERT(sizeof(struct fs) == 1376);
357#endif
358
359/*
360 * Filesystem identification
361 */
362#define FS_UFS1_MAGIC 0x011954 /* UFS1 fast filesystem magic number */
363#define FS_UFS2_MAGIC 0x19540119 /* UFS2 fast filesystem magic number */
364#define FS_BAD2_MAGIC 0x19960408 /* UFS2 incomplete newfs magic number */
365#define FS_OKAY 0x7c269d38 /* superblock checksum */
366#define FS_42INODEFMT -1 /* 4.2BSD inode format */
367#define FS_44INODEFMT 2 /* 4.4BSD inode format */
368
369/*
370 * Preference for optimization.
371 */
372#define FS_OPTTIME 0 /* minimize allocation time */
373#define FS_OPTSPACE 1 /* minimize disk fragmentation */
374
375/*
376 * Filesystem flags.
377 *
378 * The FS_UNCLEAN flag is set by the kernel when the filesystem was
379 * mounted with fs_clean set to zero. The FS_DOSOFTDEP flag indicates
380 * that the filesystem should be managed by the soft updates code.
381 * Note that the FS_NEEDSFSCK flag is set and cleared only by the
382 * fsck utility. It is set when background fsck finds an unexpected
383 * inconsistency which requires a traditional foreground fsck to be
384 * run. Such inconsistencies should only be found after an uncorrectable
385 * disk error. A foreground fsck will clear the FS_NEEDSFSCK flag when
386 * it has successfully cleaned up the filesystem. The kernel uses this
387 * flag to enforce that inconsistent filesystems be mounted read-only.
388 * The FS_INDEXDIRS flag when set indicates that the kernel maintains
389 * on-disk auxiliary indexes (such as B-trees) for speeding directory
390 * accesses. Kernels that do not support auxiliary indicies clear the
391 * flag to indicate that the indicies need to be rebuilt (by fsck) before
392 * they can be used.
393 *
394 * FS_ACLS indicates that ACLs are administratively enabled for the
395 * file system, so they should be loaded from extended attributes,
396 * observed for access control purposes, and be administered by object
397 * owners. FS_MULTILABEL indicates that the TrustedBSD MAC Framework
398 * should attempt to back MAC labels into extended attributes on the
399 * file system rather than maintain a single mount label for all
400 * objects.
401 */
402#define FS_UNCLEAN 0x01 /* filesystem not clean at mount */
403#define FS_DOSOFTDEP 0x02 /* filesystem using soft dependencies */
404#define FS_NEEDSFSCK 0x04 /* filesystem needs sync fsck before mount */
405#define FS_INDEXDIRS 0x08 /* kernel supports indexed directories */
406#define FS_ACLS 0x10 /* file system has ACLs enabled */
407#define FS_MULTILABEL 0x20 /* file system is MAC multi-label */
408#define FS_FLAGS_UPDATED 0x80 /* flags have been moved to new location */
409
410/*
411 * Macros to access bits in the fs_active array.
412 */
413#define ACTIVECGNUM(fs, cg) ((fs)->fs_active[(cg) / (NBBY * sizeof(int))])
414#define ACTIVECGOFF(cg) (1 << ((cg) % (NBBY * sizeof(int))))
415
416/*
417 * The size of a cylinder group is calculated by CGSIZE. The maximum size
418 * is limited by the fact that cylinder groups are at most one block.
419 * Its size is derived from the size of the maps maintained in the
420 * cylinder group and the (struct cg) size.
421 */
422#define CGSIZE(fs) \
423 /* base cg */ (sizeof(struct cg) + sizeof(int32_t) + \
424 /* old btotoff */ (fs)->fs_old_cpg * sizeof(int32_t) + \
425 /* old boff */ (fs)->fs_old_cpg * sizeof(u_int16_t) + \
426 /* inode map */ howmany((fs)->fs_ipg, NBBY) + \
427 /* block map */ howmany((fs)->fs_fpg, NBBY) +\
428 /* if present */ ((fs)->fs_contigsumsize <= 0 ? 0 : \
429 /* cluster sum */ (fs)->fs_contigsumsize * sizeof(int32_t) + \
430 /* cluster map */ howmany(fragstoblks(fs, (fs)->fs_fpg), NBBY)))
431
432/*
433 * The minimal number of cylinder groups that should be created.
434 */
435#define MINCYLGRPS 4
436
437/*
438 * Convert cylinder group to base address of its global summary info.
439 */
440#define fs_cs(fs, indx) fs_csp[indx]
441
442/*
443 * Cylinder group block for a filesystem.
444 */
445#define CG_MAGIC 0x090255
446struct cg {
447 int32_t cg_firstfield; /* historic cyl groups linked list */
448 int32_t cg_magic; /* magic number */
449 int32_t cg_old_time; /* time last written */
450 int32_t cg_cgx; /* we are the cgx'th cylinder group */
451 int16_t cg_old_ncyl; /* number of cyl's this cg */
452 int16_t cg_old_niblk; /* number of inode blocks this cg */
453 int32_t cg_ndblk; /* number of data blocks this cg */
454 struct csum cg_cs; /* cylinder summary information */
455 int32_t cg_rotor; /* position of last used block */
456 int32_t cg_frotor; /* position of last used frag */
457 int32_t cg_irotor; /* position of last used inode */
458 int32_t cg_frsum[MAXFRAG]; /* counts of available frags */
459 int32_t cg_old_btotoff; /* (int32) block totals per cylinder */
460 int32_t cg_old_boff; /* (u_int16) free block positions */
461 int32_t cg_iusedoff; /* (u_int8) used inode map */
462 int32_t cg_freeoff; /* (u_int8) free block map */
463 int32_t cg_nextfreeoff; /* (u_int8) next available space */
464 int32_t cg_clustersumoff; /* (u_int32) counts of avail clusters */
465 int32_t cg_clusteroff; /* (u_int8) free cluster map */
466 int32_t cg_nclusterblks; /* number of clusters this cg */
467 int32_t cg_niblk; /* number of inode blocks this cg */
468 int32_t cg_initediblk; /* last initialized inode */
469 int32_t cg_sparecon32[3]; /* reserved for future use */
470 ufs_time_t cg_time; /* time last written */
471 int64_t cg_sparecon64[3]; /* reserved for future use */
472 u_int8_t cg_space[1]; /* space for cylinder group maps */
473/* actually longer */
474};
475
476/*
477 * Macros for access to cylinder group array structures
478 */
479#define cg_chkmagic(cgp) ((cgp)->cg_magic == CG_MAGIC)
480#define cg_inosused(cgp) \
481 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_iusedoff))
482#define cg_blksfree(cgp) \
483 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_freeoff))
484#define cg_clustersfree(cgp) \
485 ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_clusteroff))
486#define cg_clustersum(cgp) \
487 ((int32_t *)((uintptr_t)(cgp) + (cgp)->cg_clustersumoff))
488
489/*
490 * Turn filesystem block numbers into disk block addresses.
491 * This maps filesystem blocks to device size blocks.
492 */
493#define fsbtodb(fs, b) ((b) << (fs)->fs_fsbtodb)
494#define dbtofsb(fs, b) ((b) >> (fs)->fs_fsbtodb)
495
496/*
497 * Cylinder group macros to locate things in cylinder groups.
498 * They calc filesystem addresses of cylinder group data structures.
499 */
500#define cgbase(fs, c) (((ufs2_daddr_t)(fs)->fs_fpg) * (c))
501#define cgdmin(fs, c) (cgstart(fs, c) + (fs)->fs_dblkno) /* 1st data */
502#define cgimin(fs, c) (cgstart(fs, c) + (fs)->fs_iblkno) /* inode blk */
503#define cgsblock(fs, c) (cgstart(fs, c) + (fs)->fs_sblkno) /* super blk */
504#define cgtod(fs, c) (cgstart(fs, c) + (fs)->fs_cblkno) /* cg block */
505#define cgstart(fs, c) \
506 ((fs)->fs_magic == FS_UFS2_MAGIC ? cgbase(fs, c) : \
507 (cgbase(fs, c) + (fs)->fs_old_cgoffset * ((c) & ~((fs)->fs_old_cgmask))))
508
509/*
510 * Macros for handling inode numbers:
511 * inode number to filesystem block offset.
512 * inode number to cylinder group number.
513 * inode number to filesystem block address.
514 */
515#define ino_to_cg(fs, x) ((x) / (fs)->fs_ipg)
516#define ino_to_fsba(fs, x) \
517 ((ufs2_daddr_t)(cgimin(fs, ino_to_cg(fs, x)) + \
518 (blkstofrags((fs), (((x) % (fs)->fs_ipg) / INOPB(fs))))))
519#define ino_to_fsbo(fs, x) ((x) % INOPB(fs))
520
521/*
522 * Give cylinder group number for a filesystem block.
523 * Give cylinder group block number for a filesystem block.
524 */
525#define dtog(fs, d) ((d) / (fs)->fs_fpg)
526#define dtogd(fs, d) ((d) % (fs)->fs_fpg)
527
528/*
529 * Extract the bits for a block from a map.
530 * Compute the cylinder and rotational position of a cyl block addr.
531 */
532#define blkmap(fs, map, loc) \
533 (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag)))
534
535/*
536 * The following macros optimize certain frequently calculated
537 * quantities by using shifts and masks in place of divisions
538 * modulos and multiplications.
539 */
540#define blkoff(fs, loc) /* calculates (loc % fs->fs_bsize) */ \
541 ((loc) & (fs)->fs_qbmask)
542#define fragoff(fs, loc) /* calculates (loc % fs->fs_fsize) */ \
543 ((loc) & (fs)->fs_qfmask)
544#define lfragtosize(fs, frag) /* calculates ((off_t)frag * fs->fs_fsize) */ \
545 (((off_t)(frag)) << (fs)->fs_fshift)
546#define lblktosize(fs, blk) /* calculates ((off_t)blk * fs->fs_bsize) */ \
547 (((off_t)(blk)) << (fs)->fs_bshift)
548/* Use this only when `blk' is known to be small, e.g., < NDADDR. */
549#define smalllblktosize(fs, blk) /* calculates (blk * fs->fs_bsize) */ \
550 ((blk) << (fs)->fs_bshift)
551#define lblkno(fs, loc) /* calculates (loc / fs->fs_bsize) */ \
552 ((loc) >> (fs)->fs_bshift)
553#define numfrags(fs, loc) /* calculates (loc / fs->fs_fsize) */ \
554 ((loc) >> (fs)->fs_fshift)
555#define blkroundup(fs, size) /* calculates roundup(size, fs->fs_bsize) */ \
556 (((size) + (fs)->fs_qbmask) & (fs)->fs_bmask)
557#define fragroundup(fs, size) /* calculates roundup(size, fs->fs_fsize) */ \
558 (((size) + (fs)->fs_qfmask) & (fs)->fs_fmask)
559#define fragstoblks(fs, frags) /* calculates (frags / fs->fs_frag) */ \
560 ((frags) >> (fs)->fs_fragshift)
561#define blkstofrags(fs, blks) /* calculates (blks * fs->fs_frag) */ \
562 ((blks) << (fs)->fs_fragshift)
563#define fragnum(fs, fsb) /* calculates (fsb % fs->fs_frag) */ \
564 ((fsb) & ((fs)->fs_frag - 1))
565#define blknum(fs, fsb) /* calculates rounddown(fsb, fs->fs_frag) */ \
566 ((fsb) &~ ((fs)->fs_frag - 1))
567
568/*
569 * Determine the number of available frags given a
570 * percentage to hold in reserve.
571 */
572#define freespace(fs, percentreserved) \
573 (blkstofrags((fs), (fs)->fs_cstotal.cs_nbfree) + \
574 (fs)->fs_cstotal.cs_nffree - \
575 (((off_t)((fs)->fs_dsize)) * (percentreserved) / 100))
576
577/*
578 * Determining the size of a file block in the filesystem.
579 */
580#define blksize(fs, ip, lbn) \
581 (((lbn) >= NDADDR || (ip)->i_size >= smalllblktosize(fs, (lbn) + 1)) \
582 ? (fs)->fs_bsize \
583 : (fragroundup(fs, blkoff(fs, (ip)->i_size))))
584#define sblksize(fs, size, lbn) \
585 (((lbn) >= NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \
586 ? (fs)->fs_bsize \
587 : (fragroundup(fs, blkoff(fs, (size)))))
588
589
590/*
591 * Number of inodes in a secondary storage block/fragment.
592 */
593#define INOPB(fs) ((fs)->fs_inopb)
594#define INOPF(fs) ((fs)->fs_inopb >> (fs)->fs_fragshift)
595
596/*
597 * Number of indirects in a filesystem block.
598 */
599#define NINDIR(fs) ((fs)->fs_nindir)
600
601extern int inside[], around[];
602extern u_char *fragtbl[];
603
604#endif