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33 * @(#)fs.h 8.13 (Berkeley) 3/21/95
35 * $DragonFly: src/sys/boot/common/fs.h,v 1.1 2003/11/10 06:08:31 dillon Exp $
38 #ifndef _UFS_FFS_FS_H_
39 #define _UFS_FFS_FS_H_
42 * Each disk drive contains some number of filesystems.
43 * A filesystem consists of a number of cylinder groups.
44 * Each cylinder group has inodes and data.
46 * A filesystem is described by its super-block, which in turn
47 * describes the cylinder groups. The super-block is critical
48 * data and is replicated in each cylinder group to protect against
49 * catastrophic loss. This is done at `newfs' time and the critical
50 * super-block data does not change, so the copies need not be
51 * referenced further unless disaster strikes.
53 * For filesystem fs, the offsets of the various blocks of interest
54 * are given in the super block as:
55 * [fs->fs_sblkno] Super-block
56 * [fs->fs_cblkno] Cylinder group block
57 * [fs->fs_iblkno] Inode blocks
58 * [fs->fs_dblkno] Data blocks
59 * The beginning of cylinder group cg in fs, is given by
60 * the ``cgbase(fs, cg)'' macro.
62 * Depending on the architecture and the media, the superblock may
63 * reside in any one of four places. For tiny media where every block
64 * counts, it is placed at the very front of the partition. Historically,
65 * UFS1 placed it 8K from the front to leave room for the disk label and
66 * a small bootstrap. For UFS2 it got moved to 64K from the front to leave
67 * room for the disk label and a bigger bootstrap, and for really piggy
68 * systems we check at 256K from the front if the first three fail. In
69 * all cases the size of the superblock will be SBLOCKSIZE. All values are
70 * given in byte-offset form, so they do not imply a sector size. The
71 * SBLOCKSEARCH specifies the order in which the locations should be searched.
73 #define SBLOCK_FLOPPY 0
74 #define SBLOCK_UFS1 8192
75 #define SBLOCK_UFS2 65536
76 #define SBLOCK_PIGGY 262144
77 #define SBLOCKSIZE 8192
78 #define SBLOCKSEARCH \
79 { SBLOCK_UFS2, SBLOCK_UFS1, SBLOCK_FLOPPY, SBLOCK_PIGGY, -1 }
82 * Max number of fragments per block. This value is NOT tweakable.
87 * Addresses stored in inodes are capable of addressing fragments
88 * of `blocks'. File system blocks of at most size MAXBSIZE can
89 * be optionally broken into 2, 4, or 8 pieces, each of which is
90 * addressable; these pieces may be DEV_BSIZE, or some multiple of
93 * Large files consist of exclusively large data blocks. To avoid
94 * undue wasted disk space, the last data block of a small file may be
95 * allocated as only as many fragments of a large block as are
96 * necessary. The filesystem format retains only a single pointer
97 * to such a fragment, which is a piece of a single large block that
98 * has been divided. The size of such a fragment is determinable from
99 * information in the inode, using the ``blksize(fs, ip, lbn)'' macro.
101 * The filesystem records space availability at the fragment level;
102 * to determine block availability, aligned fragments are examined.
106 * MINBSIZE is the smallest allowable block size.
107 * In order to insure that it is possible to create files of size
108 * 2^32 with only two levels of indirection, MINBSIZE is set to 4096.
109 * MINBSIZE must be big enough to hold a cylinder group block,
110 * thus changes to (struct cg) must keep its size within MINBSIZE.
111 * Note that super blocks are always of size SBSIZE,
112 * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE.
114 #define MINBSIZE 4096
117 * The path name on which the filesystem is mounted is maintained
118 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in
119 * the super block for this name.
121 #define MAXMNTLEN 468
124 * The volume name for this filesystem is maintained in fs_volname.
125 * MAXVOLLEN defines the length of the buffer allocated.
130 * There is a 128-byte region in the superblock reserved for in-core
131 * pointers to summary information. Originally this included an array
132 * of pointers to blocks of struct csum; now there are just a few
133 * pointers and the remaining space is padded with fs_ocsp[].
135 * NOCSPTRS determines the size of this padding. One pointer (fs_csp)
136 * is taken away to point to a contiguous array of struct csum for
137 * all cylinder groups; a second (fs_maxcluster) points to an array
138 * of cluster sizes that is computed as cylinder groups are inspected,
139 * and the third points to an array that tracks the creation of new
140 * directories. A fourth pointer, fs_active, is used when creating
141 * snapshots; it points to a bitmap of cylinder groups for which the
142 * free-block bitmap has changed since the snapshot operation began.
144 #define NOCSPTRS ((128 / sizeof(void *)) - 4)
147 * A summary of contiguous blocks of various sizes is maintained
148 * in each cylinder group. Normally this is set by the initial
149 * value of fs_maxcontig. To conserve space, a maximum summary size
150 * is set by FS_MAXCONTIG.
152 #define FS_MAXCONTIG 16
155 * MINFREE gives the minimum acceptable percentage of filesystem
156 * blocks which may be free. If the freelist drops below this level
157 * only the superuser may continue to allocate blocks. This may
158 * be set to 0 if no reserve of free blocks is deemed necessary,
159 * however throughput drops by fifty percent if the filesystem
160 * is run at between 95% and 100% full; thus the minimum default
161 * value of fs_minfree is 5%. However, to get good clustering
162 * performance, 10% is a better choice. hence we use 10% as our
163 * default value. With 10% free space, fragmentation is not a
164 * problem, so we choose to optimize for time.
167 #define DEFAULTOPT FS_OPTTIME
170 * Grigoriy Orlov <gluk@ptci.ru> has done some extensive work to fine
171 * tune the layout preferences for directories within a filesystem.
172 * His algorithm can be tuned by adjusting the following parameters
173 * which tell the system the average file size and the average number
174 * of files per directory. These defaults are well selected for typical
175 * filesystems, but may need to be tuned for odd cases like filesystems
176 * being used for sqiud caches or news spools.
178 #define AVFILESIZ 16384 /* expected average file size */
179 #define AFPDIR 64 /* expected number of files per directory */
182 * The maximum number of snapshot nodes that can be associated
183 * with each filesystem. This limit affects only the number of
184 * snapshot files that can be recorded within the superblock so
185 * that they can be found when the filesystem is mounted. However,
186 * maintaining too many will slow the filesystem performance, so
187 * having this limit is a good idea.
192 * Used to identify special blocks in snapshots:
194 * BLK_NOCOPY - A block that was unallocated at the time the snapshot
195 * was taken, hence does not need to be copied when written.
196 * BLK_SNAP - A block held by another snapshot that is not needed by this
197 * snapshot. When the other snapshot is freed, the BLK_SNAP entries
198 * are converted to BLK_NOCOPY. These are needed to allow fsck to
199 * identify blocks that are in use by other snapshots (which are
200 * expunged from this snapshot).
202 #define BLK_NOCOPY ((ufs2_daddr_t)(1))
203 #define BLK_SNAP ((ufs2_daddr_t)(2))
206 * Sysctl values for the fast filesystem.
208 #define FFS_ADJ_REFCNT 1 /* adjust inode reference count */
209 #define FFS_ADJ_BLKCNT 2 /* adjust inode used block count */
210 #define FFS_BLK_FREE 3 /* free range of blocks in map */
211 #define FFS_DIR_FREE 4 /* free specified dir inodes in map */
212 #define FFS_FILE_FREE 5 /* free specified file inodes in map */
213 #define FFS_SET_FLAGS 6 /* set filesystem flags */
214 #define FFS_MAXID 7 /* number of valid ffs ids */
217 * Command structure passed in to the filesystem to adjust filesystem values.
219 #define FFS_CMD_VERSION 0x19790518 /* version ID */
221 int32_t version
; /* version of command structure */
222 int32_t handle
; /* reference to filesystem to be changed */
223 int64_t value
; /* inode or block number to be affected */
224 int64_t size
; /* amount or range to be adjusted */
225 int64_t spare
; /* reserved for future use */
229 * Per cylinder group information; summarized in blocks allocated
230 * from first cylinder group data blocks. These blocks have to be
231 * read in from fs_csaddr (size fs_cssize) in addition to the
235 int32_t cs_ndir
; /* number of directories */
236 int32_t cs_nbfree
; /* number of free blocks */
237 int32_t cs_nifree
; /* number of free inodes */
238 int32_t cs_nffree
; /* number of free frags */
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_numclusters
; /* number of free clusters */
246 int64_t cs_spare
[3]; /* future expansion */
250 * Super block for an FFS filesystem.
253 int32_t fs_firstfield
; /* historic filesystem linked list, */
254 int32_t fs_unused_1
; /* used for incore super blocks */
255 int32_t fs_sblkno
; /* offset 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 */
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 int32_t fs_old_npsect
; /* # sectors/track including spares */
292 int32_t fs_old_interleave
; /* hardware sector interleave */
293 int32_t fs_old_trackskew
; /* sector 0 skew, per track */
294 int32_t fs_id
[2]; /* unique filesystem id */
295 /* sizes determined by number of cylinder groups and their sizes */
296 int32_t fs_old_csaddr
; /* blk addr of cyl grp summary area */
297 int32_t fs_cssize
; /* size of cyl grp summary area */
298 int32_t fs_cgsize
; /* cylinder group size */
299 int32_t fs_spare2
; /* old fs_ntrak */
300 int32_t fs_old_nsect
; /* sectors per track */
301 int32_t fs_old_spc
; /* sectors per cylinder */
302 int32_t fs_old_ncyl
; /* cylinders in filesystem */
303 int32_t fs_old_cpg
; /* cylinders per group */
304 int32_t fs_ipg
; /* inodes per group */
305 int32_t fs_fpg
; /* blocks per group * fs_frag */
306 /* this data must be re-computed after crashes */
307 struct csum fs_old_cstotal
; /* cylinder summary information */
308 /* these fields are cleared at mount time */
309 int8_t fs_fmod
; /* super block modified flag */
310 int8_t fs_clean
; /* filesystem is clean flag */
311 int8_t fs_ronly
; /* mounted read-only flag */
312 int8_t fs_old_flags
; /* old FS_ flags */
313 u_char fs_fsmnt
[MAXMNTLEN
]; /* name mounted on */
314 u_char fs_volname
[MAXVOLLEN
]; /* volume name */
315 u_int64_t fs_swuid
; /* system-wide uid */
316 int32_t fs_pad
; /* due to alignment of fs_swuid */
317 /* these fields retain the current block allocation info */
318 int32_t fs_cgrotor
; /* last cg searched */
319 void *fs_ocsp
[NOCSPTRS
]; /* padding; was list of fs_cs buffers */
320 u_int8_t
*fs_contigdirs
; /* # of contiguously allocated dirs */
321 struct csum
*fs_csp
; /* cg summary info buffer for fs_cs */
322 int32_t *fs_maxcluster
; /* max cluster in each cyl group */
323 u_int
*fs_active
; /* used by snapshots to track fs */
324 int32_t fs_old_cpc
; /* cyl per cycle in postbl */
325 int32_t fs_maxbsize
; /* maximum blocking factor permitted */
326 int64_t fs_sparecon64
[17]; /* old rotation block list head */
327 int64_t fs_sblockloc
; /* byte offset of standard superblock */
328 struct csum_total fs_cstotal
; /* cylinder summary information */
329 ufs_time_t fs_time
; /* last time written */
330 int64_t fs_size
; /* number of blocks in fs */
331 int64_t fs_dsize
; /* number of data blocks in fs */
332 ufs2_daddr_t fs_csaddr
; /* blk addr of cyl grp summary area */
333 int64_t fs_pendingblocks
; /* blocks in process of being freed */
334 int32_t fs_pendinginodes
; /* inodes in process of being freed */
335 int32_t fs_snapinum
[FSMAXSNAP
];/* list of snapshot inode numbers */
336 int32_t fs_avgfilesize
; /* expected average file size */
337 int32_t fs_avgfpdir
; /* expected # of files per directory */
338 int32_t fs_save_cgsize
; /* save real cg size to use fs_bsize */
339 int32_t fs_sparecon32
[26]; /* reserved for future constants */
340 int32_t fs_flags
; /* see FS_ flags below */
341 int32_t fs_contigsumsize
; /* size of cluster summary array */
342 int32_t fs_maxsymlinklen
; /* max length of an internal symlink */
343 int32_t fs_old_inodefmt
; /* format of on-disk inodes */
344 u_int64_t fs_maxfilesize
; /* maximum representable file size */
345 int64_t fs_qbmask
; /* ~fs_bmask for use with 64-bit size */
346 int64_t fs_qfmask
; /* ~fs_fmask for use with 64-bit size */
347 int32_t fs_state
; /* validate fs_clean field */
348 int32_t fs_old_postblformat
; /* format of positional layout tables */
349 int32_t fs_old_nrpos
; /* number of rotational positions */
350 int32_t fs_spare5
[2]; /* old fs_postbloff */
351 /* old fs_rotbloff */
352 int32_t fs_magic
; /* magic number */
355 /* Sanity checking. */
357 CTASSERT(sizeof(struct fs
) == 1376);
361 * Filesystem identification
363 #define FS_UFS1_MAGIC 0x011954 /* UFS1 fast filesystem magic number */
364 #define FS_UFS2_MAGIC 0x19540119 /* UFS2 fast filesystem 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 */
370 * Preference for optimization.
372 #define FS_OPTTIME 0 /* minimize allocation time */
373 #define FS_OPTSPACE 1 /* minimize disk fragmentation */
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
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
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 */
411 * Macros to access bits in the fs_active array.
413 #define ACTIVECGNUM(fs, cg) ((fs)->fs_active[(cg) / (NBBY * sizeof(int))])
414 #define ACTIVECGOFF(cg) (1 << ((cg) % (NBBY * sizeof(int))))
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.
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)))
433 * The minimal number of cylinder groups that should be created.
438 * Convert cylinder group to base address of its global summary info.
440 #define fs_cs(fs, indx) fs_csp[indx]
443 * Cylinder group block for a filesystem.
445 #define CG_MAGIC 0x090255
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 */
477 * Macros for access to cylinder group array structures
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 *)((u_int8_t *)(cgp) + (cgp)->cg_clustersumoff))
490 * Turn filesystem block numbers into disk block addresses.
491 * This maps filesystem blocks to device size blocks.
493 #define fsbtodb(fs, b) ((b) << (fs)->fs_fsbtodb)
494 #define dbtofsb(fs, b) ((b) >> (fs)->fs_fsbtodb)
497 * Cylinder group macros to locate things in cylinder groups.
498 * They calc filesystem addresses of cylinder group data structures.
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))))
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.
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))
522 * Give cylinder group number for a filesystem block.
523 * Give cylinder group block number for a filesystem block.
525 #define dtog(fs, d) ((d) / (fs)->fs_fpg)
526 #define dtogd(fs, d) ((d) % (fs)->fs_fpg)
529 * Extract the bits for a block from a map.
530 * Compute the cylinder and rotational position of a cyl block addr.
532 #define blkmap(fs, map, loc) \
533 (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag)))
536 * The following macros optimize certain frequently calculated
537 * quantities by using shifts and masks in place of divisions
538 * modulos and multiplications.
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))
569 * Determine the number of available frags given a
570 * percentage to hold in reserve.
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))
578 * Determining the size of a file block in the filesystem.
580 #define blksize(fs, ip, lbn) \
581 (((lbn) >= NDADDR || (ip)->i_size >= smalllblktosize(fs, (lbn) + 1)) \
583 : (fragroundup(fs, blkoff(fs, (ip)->i_size))))
584 #define sblksize(fs, size, lbn) \
585 (((lbn) >= NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \
587 : (fragroundup(fs, blkoff(fs, (size)))))
591 * Number of inodes in a secondary storage block/fragment.
593 #define INOPB(fs) ((fs)->fs_inopb)
594 #define INOPF(fs) ((fs)->fs_inopb >> (fs)->fs_fragshift)
597 * Number of indirects in a filesystem block.
599 #define NINDIR(fs) ((fs)->fs_nindir)
601 extern int inside
[], around
[];
602 extern u_char
*fragtbl
[];