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/* $OpenBSD: fs.h,v 1.32 2007/06/01 07:03:27 otto Exp $ */
/* $NetBSD: fs.h,v 1.6 1995/04/12 21:21:02 mycroft Exp $ */
/*
* Copyright (c) 1982, 1986, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)fs.h 8.10 (Berkeley) 10/27/94
*/
/*
* Each disk drive contains some number of file systems.
* A file system consists of a number of cylinder groups.
* Each cylinder group has inodes and data.
*
* A file system is described by its super-block, which in turn
* describes the cylinder groups. The super-block is critical
* data and is replicated in each cylinder group to protect against
* catastrophic loss. This is done at `newfs' time and the critical
* super-block data does not change, so the copies need not be
* referenced further unless disaster strikes.
*
* For file system fs, the offsets of the various blocks of interest
* are given in the super block as:
* [fs->fs_sblkno] Super-block
* [fs->fs_cblkno] Cylinder group block
* [fs->fs_iblkno] Inode blocks
* [fs->fs_dblkno] Data blocks
* The beginning of cylinder group cg in fs, is given by
* the ``cgbase(fs, cg)'' macro.
*
* The first boot and super blocks are given in absolute disk addresses.
* The byte-offset forms are preferred, as they don't imply a sector size.
*/
#define BBSIZE 8192
#define SBSIZE 8192
#define BBOFF ((off_t)(0))
#define SBOFF ((off_t)(BBOFF + BBSIZE))
#define BBLOCK ((daddr_t)(0))
#define SBLOCK ((daddr_t)(BBLOCK + BBSIZE / DEV_BSIZE))
#define SBLOCK_UFS1 8192
#define SBLOCK_UFS2 65536
#define SBLOCK_PIGGY 262144
#define SBLOCKSIZE 8192
#define SBLOCKSEARCH \
{ SBLOCK_UFS2, SBLOCK_UFS1, SBLOCK_PIGGY, -1 }
/*
* Addresses stored in inodes are capable of addressing fragments
* of `blocks'. File system blocks of at most size MAXBSIZE can
* be optionally broken into 2, 4, or 8 pieces, each of which is
* addressible; these pieces may be DEV_BSIZE, or some multiple of
* a DEV_BSIZE unit.
*
* Large files consist of exclusively large data blocks. To avoid
* undue wasted disk space, the last data block of a small file may be
* allocated as only as many fragments of a large block as are
* necessary. The file system format retains only a single pointer
* to such a fragment, which is a piece of a single large block that
* has been divided. The size of such a fragment is determinable from
* information in the inode, using the ``blksize(fs, ip, lbn)'' macro.
*
* The file system records space availability at the fragment level;
* to determine block availability, aligned fragments are examined.
*/
/*
* MINBSIZE is the smallest allowable block size.
* In order to insure that it is possible to create files of size
* 2^32 with only two levels of indirection, MINBSIZE is set to 4096.
* MINBSIZE must be big enough to hold a cylinder group block,
* thus changes to (struct cg) must keep its size within MINBSIZE.
* Note that super blocks are always of size SBSIZE,
* and that both SBSIZE and MAXBSIZE must be >= MINBSIZE.
*/
#define MINBSIZE 4096
/*
* The path name on which the file system is mounted is maintained
* in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in
* the super block for this name.
*/
#define MAXMNTLEN 468
/*
* The volume name for this file system is kept in fs_volname.
* MAXVOLLEN defines the length of the buffer allocated.
*/
#define MAXVOLLEN 32
/*
* There is a 128-byte region in the superblock reserved for in-core
* pointers to summary information. Originally this included an array
* of pointers to blocks of struct csum; now there are just three
* pointers and the remaining space is padded with fs_ocsp[].
*
* NOCSPTRS determines the size of this padding. One pointer (fs_csp)
* is taken away to point to a contiguous array of struct csum for
* all cylinder groups; a second (fs_maxcluster) points to an array
* of cluster sizes that is computed as cylinder groups are inspected,
* and the third points to an array that tracks the creation of new
* directories.
*/
#define NOCSPTRS ((128 / sizeof(void *)) - 4)
/*
* A summary of contiguous blocks of various sizes is maintained
* in each cylinder group. Normally this is set by the initial
* value of fs_maxcontig. To conserve space, a maximum summary size
* is set by FS_MAXCONTIG.
*/
#define FS_MAXCONTIG 16
/*
* MINFREE gives the minimum acceptable percentage of file system
* blocks which may be free. If the freelist drops below this level
* only the superuser may continue to allocate blocks. This may
* be set to 0 if no reserve of free blocks is deemed necessary,
* however throughput drops by fifty percent if the file system
* is run at between 95% and 100% full; thus the minimum default
* value of fs_minfree is 5%. However, to get good clustering
* performance, 10% is a better choice. With 5% free space,
* fragmentation is not a problem, so we choose to optimize for time.
*/
#define MINFREE 5
#define DEFAULTOPT FS_OPTTIME
/*
* The directory preference algorithm(dirpref) can be tuned by adjusting
* the following parameters which tell the system the average file size
* and the average number of files per directory. These defaults are well
* selected for typical filesystems, but may need to be tuned for odd
* cases like filesystems being used for sqiud caches or news spools.
*/
#define AVFILESIZ 16384 /* expected average file size */
#define AFPDIR 64 /* expected number of files per directory */
/*
* Size of superblock space reserved for snapshots.
*/
#define FSMAXSNAP 20
/*
* Per cylinder group information; summarized in blocks allocated
* from first cylinder group data blocks. These blocks have to be
* read in from fs_csaddr (size fs_cssize) in addition to the
* super block.
*/
struct csum {
int32_t cs_ndir; /* number of directories */
int32_t cs_nbfree; /* number of free blocks */
int32_t cs_nifree; /* number of free inodes */
int32_t cs_nffree; /* number of free frags */
};
struct csum_total {
int64_t cs_ndir; /* number of directories */
int64_t cs_nbfree; /* number of free blocks */
int64_t cs_nifree; /* number of free inodes */
int64_t cs_nffree; /* number of free frags */
int64_t cs_spare[4]; /* future expansion */
};
/*
* Super block for an FFS file system.
*/
struct fs {
int32_t fs_firstfield; /* historic file system linked list, */
int32_t fs_unused_1; /* used for incore super blocks */
int32_t fs_sblkno; /* addr of super-block / frags */
int32_t fs_cblkno; /* offset of cyl-block / frags */
int32_t fs_iblkno; /* offset of inode-blocks / frags */
int32_t fs_dblkno; /* offset of first data / frags */
int32_t fs_cgoffset; /* cylinder group offset in cylinder */
int32_t fs_cgmask; /* used to calc mod fs_ntrak */
int32_t fs_ffs1_time; /* last time written */
int32_t fs_ffs1_size; /* # of blocks in fs / frags */
int32_t fs_ffs1_dsize; /* # of data blocks in fs */
int32_t fs_ncg; /* # of cylinder groups */
int32_t fs_bsize; /* size of basic blocks / bytes */
int32_t fs_fsize; /* size of frag blocks / bytes */
int32_t fs_frag; /* # of frags in a block in fs */
/* these are configuration parameters */
int32_t fs_minfree; /* minimum percentage of free blocks */
int32_t fs_rotdelay; /* # of ms for optimal next block */
int32_t fs_rps; /* disk revolutions per second */
/* these fields can be computed from the others */
int32_t fs_bmask; /* ``blkoff'' calc of blk offsets */
int32_t fs_fmask; /* ``fragoff'' calc of frag offsets */
int32_t fs_bshift; /* ``lblkno'' calc of logical blkno */
int32_t fs_fshift; /* ``numfrags'' calc # of frags */
/* these are configuration parameters */
int32_t fs_maxcontig; /* max # of contiguous blks */
int32_t fs_maxbpg; /* max # of blks per cyl group */
/* these fields can be computed from the others */
int32_t fs_fragshift; /* block to frag shift */
int32_t fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */
int32_t fs_sbsize; /* actual size of super block */
int32_t fs_csmask; /* csum block offset (now unused) */
int32_t fs_csshift; /* csum block number (now unused) */
int32_t fs_nindir; /* value of NINDIR */
int32_t fs_inopb; /* inodes per file system block */
int32_t fs_nspf; /* value of NSPF */
/* yet another configuration parameter */
int32_t fs_optim; /* optimization preference, see below */
/* these fields are derived from the hardware */
int32_t fs_npsect; /* # sectors/track including spares */
int32_t fs_interleave; /* hardware sector interleave */
int32_t fs_trackskew; /* sector 0 skew, per track */
/* fs_id takes the space of the unused fs_headswitch and fs_trkseek fields */
int32_t fs_id[2]; /* unique filesystem id */
/* sizes determined by number of cylinder groups and their sizes */
int32_t fs_ffs1_csaddr; /* blk addr of cyl grp summary area */
int32_t fs_cssize; /* cyl grp summary area size / bytes */
int32_t fs_cgsize; /* cyl grp block size / bytes */
/* these fields are derived from the hardware */
int32_t fs_ntrak; /* tracks per cylinder */
int32_t fs_nsect; /* sectors per track */
int32_t fs_spc; /* sectors per cylinder */
/* this comes from the disk driver partitioning */
int32_t fs_ncyl; /* cylinders in file system */
/* these fields can be computed from the others */
int32_t fs_cpg; /* cylinders per group */
int32_t fs_ipg; /* inodes per group */
int32_t fs_fpg; /* blocks per group * fs_frag */
/* this data must be re-computed after crashes */
struct csum fs_ffs1_cstotal; /* cylinder summary information */
/* these fields are cleared at mount time */
int8_t fs_fmod; /* super block modified flag */
int8_t fs_clean; /* file system is clean flag */
int8_t fs_ronly; /* mounted read-only flag */
int8_t fs_ffs1_flags; /* see FS_ below */
u_char fs_fsmnt[MAXMNTLEN]; /* name mounted on */
u_char fs_volname[MAXVOLLEN]; /* volume name */
u_int64_t fs_swuid; /* system-wide uid */
int32_t fs_pad; /* due to alignment of fs_swuid */
/* these fields retain the current block allocation info */
int32_t fs_cgrotor; /* last cg searched */
void *fs_ocsp[NOCSPTRS]; /* padding; was list of fs_cs buffers */
u_int8_t *fs_contigdirs; /* # of contiguously allocated dirs */
struct csum *fs_csp; /* cg summary info buffer for fs_cs */
int32_t *fs_maxcluster; /* max cluster in each cyl group */
u_char *fs_active; /* reserved for snapshots */
int32_t fs_cpc; /* cyl per cycle in postbl */
/* this area is only allocated if fs_ffs1_flags & FS_FLAGS_UPDATED */
int32_t fs_maxbsize; /* maximum blocking factor permitted */
int64_t fs_spareconf64[17]; /* old rotation block list head */
int64_t fs_sblockloc; /* offset of standard super block */
struct csum_total fs_cstotal; /* cylinder summary information */
int64_t fs_time; /* time last written */
int64_t fs_size; /* number of blocks in fs */
int64_t fs_dsize; /* number of data blocks in fs */
int64_t fs_csaddr; /* blk addr of cyl grp summary area */
int64_t fs_pendingblocks; /* blocks in process of being freed */
int32_t fs_pendinginodes; /* inodes in process of being freed */
int32_t fs_snapinum[FSMAXSNAP];/* space reserved for snapshots */
/* back to stuff that has been around a while */
int32_t fs_avgfilesize; /* expected average file size */
int32_t fs_avgfpdir; /* expected # of files per directory */
int32_t fs_sparecon[26]; /* reserved for future constants */
u_int32_t fs_flags; /* see FS_ flags below */
int32_t fs_fscktime; /* last time fsck(8)ed */
int32_t fs_contigsumsize; /* size of cluster summary array */
int32_t fs_maxsymlinklen; /* max length of an internal symlink */
int32_t fs_inodefmt; /* format of on-disk inodes */
u_int64_t fs_maxfilesize; /* maximum representable file size */
int64_t fs_qbmask; /* ~fs_bmask - for use with quad size */
int64_t fs_qfmask; /* ~fs_fmask - for use with quad size */
int32_t fs_state; /* validate fs_clean field */
int32_t fs_postblformat; /* format of positional layout tables */
int32_t fs_nrpos; /* number of rotational positions */
int32_t fs_postbloff; /* (u_int16) rotation block list head */
int32_t fs_rotbloff; /* (u_int8) blocks for each rotation */
int32_t fs_magic; /* magic number */
u_int8_t fs_space[1]; /* list of blocks for each rotation */
/* actually longer */
};
/*
* Filesystem identification
*/
#define FS_MAGIC 0x011954 /* the fast filesystem magic number */
#define FS_UFS1_MAGIC 0x011954 /* the fast filesystem magic number */
#define FS_UFS2_MAGIC 0x19540119 /* UFS fast filesystem magic number */
#define FS_OKAY 0x7c269d38 /* superblock checksum */
#define FS_42INODEFMT -1 /* 4.2BSD inode format */
#define FS_44INODEFMT 2 /* 4.4BSD inode format */
/*
* Filesystem clean flags
*/
#define FS_ISCLEAN 0x01
#define FS_WASCLEAN 0x02
/*
* Preference for optimization.
*/
#define FS_OPTTIME 0 /* minimize allocation time */
#define FS_OPTSPACE 1 /* minimize disk fragmentation */
/*
* Filesystem flags.
*/
#define FS_UNCLEAN 0x01 /* filesystem not clean at mount */
#define FS_DOSOFTDEP 0x02 /* filesystem using soft dependencies */
/*
* The following flag is used to detect a FFS1 file system that had its flags
* moved to the new (FFS2) location for compatibility.
*/
#define FS_FLAGS_UPDATED 0x80 /* file system has FFS2-like flags */
/*
* Rotational layout table format types
*/
#define FS_42POSTBLFMT -1 /* 4.2BSD rotational table format */
#define FS_DYNAMICPOSTBLFMT 1 /* dynamic rotational table format */
/*
* Macros for access to superblock array structures
*/
#define fs_rotbl(fs) \
(((fs)->fs_postblformat == FS_42POSTBLFMT) \
? ((fs)->fs_space) \
: ((u_int8_t *)((u_int8_t *)(fs) + (fs)->fs_rotbloff)))
/*
* The size of a cylinder group is calculated by CGSIZE. The maximum size
* is limited by the fact that cylinder groups are at most one block.
* Its size is derived from the size of the maps maintained in the
* cylinder group and the (struct cg) size.
*/
#define CGSIZE(fs) \
/* base cg */ (sizeof(struct cg) + sizeof(int32_t) + \
/* blktot size */ (fs)->fs_cpg * sizeof(int32_t) + \
/* blks size */ (fs)->fs_cpg * (fs)->fs_nrpos * sizeof(int16_t) + \
/* inode map */ howmany((fs)->fs_ipg, NBBY) + \
/* block map */ howmany((fs)->fs_fpg, NBBY) + \
/* if present */ ((fs)->fs_contigsumsize <= 0 ? 0 : \
/* cluster sum */ (fs)->fs_contigsumsize * sizeof(int32_t) + \
/* cluster map */ howmany(fragstoblks(fs, (fs)->fs_fpg), NBBY)))
/*
* Convert cylinder group to base address of its global summary info.
*/
#define fs_cs(fs, indx) fs_csp[indx]
/*
* Cylinder group block for a file system.
*/
#define CG_MAGIC 0x090255
struct cg {
int32_t cg_firstfield; /* historic cyl groups linked list */
int32_t cg_magic; /* magic number */
int32_t cg_time; /* time last written */
int32_t cg_cgx; /* we are the cgx'th cylinder group */
int16_t cg_ncyl; /* number of cyl's this cg */
int16_t cg_niblk; /* number of inode blocks this cg */
int32_t cg_ndblk; /* number of data blocks this cg */
struct csum cg_cs; /* cylinder summary information */
int32_t cg_rotor; /* position of last used block */
int32_t cg_frotor; /* position of last used frag */
int32_t cg_irotor; /* position of last used inode */
int32_t cg_frsum[MAXFRAG]; /* counts of available frags */
int32_t cg_btotoff; /* (int32) block totals per cylinder */
int32_t cg_boff; /* (u_int16) free block positions */
int32_t cg_iusedoff; /* (u_int8) used inode map */
int32_t cg_freeoff; /* (u_int8) free block map */
int32_t cg_nextfreeoff; /* (u_int8) next available space */
int32_t cg_clustersumoff; /* (u_int32) counts of avail clusters */
int32_t cg_clusteroff; /* (u_int8) free cluster map */
int32_t cg_nclusterblks; /* number of clusters this cg */
int32_t cg_ffs2_niblk; /* number of inode blocks this cg */
int32_t cg_initediblk; /* last initialized inode */
int32_t cg_sparecon32[3]; /* reserved for future use */
int64_t cg_ffs2_time; /* time last written */
int64_t cg_sparecon64[3]; /* reserved for future use */
/* actually longer */
};
/*
* Macros for access to cylinder group array structures
*/
#define cg_blktot(cgp) \
(((cgp)->cg_magic != CG_MAGIC) \
? (((struct ocg *)(cgp))->cg_btot) \
: ((int32_t *)((u_int8_t *)(cgp) + (cgp)->cg_btotoff)))
#define cg_blks(fs, cgp, cylno) \
(((cgp)->cg_magic != CG_MAGIC) \
? (((struct ocg *)(cgp))->cg_b[cylno]) \
: ((int16_t *)((u_int8_t *)(cgp) + \
(cgp)->cg_boff) + (cylno) * (fs)->fs_nrpos))
#define cg_inosused(cgp) \
(((cgp)->cg_magic != CG_MAGIC) \
? (((struct ocg *)(cgp))->cg_iused) \
: ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_iusedoff)))
#define cg_blksfree(cgp) \
(((cgp)->cg_magic != CG_MAGIC) \
? (((struct ocg *)(cgp))->cg_free) \
: ((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_freeoff)))
#define cg_chkmagic(cgp) \
((cgp)->cg_magic == CG_MAGIC || ((struct ocg *)(cgp))->cg_magic == CG_MAGIC)
#define cg_clustersfree(cgp) \
((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_clusteroff))
#define cg_clustersum(cgp) \
((int32_t *)((u_int8_t *)(cgp) + (cgp)->cg_clustersumoff))
/*
* The following structure is defined
* for compatibility with old file systems.
*/
struct ocg {
int32_t cg_firstfield; /* historic linked list of cyl groups */
int32_t cg_unused_1; /* used for incore cyl groups */
int32_t cg_time; /* time last written */
int32_t cg_cgx; /* we are the cgx'th cylinder group */
int16_t cg_ncyl; /* number of cyl's this cg */
int16_t cg_niblk; /* number of inode blocks this cg */
int32_t cg_ndblk; /* number of data blocks this cg */
struct csum cg_cs; /* cylinder summary information */
int32_t cg_rotor; /* position of last used block */
int32_t cg_frotor; /* position of last used frag */
int32_t cg_irotor; /* position of last used inode */
int32_t cg_frsum[8]; /* counts of available frags */
int32_t cg_btot[32]; /* block totals per cylinder */
int16_t cg_b[32][8]; /* positions of free blocks */
u_int8_t cg_iused[256]; /* used inode map */
int32_t cg_magic; /* magic number */
u_int8_t cg_free[1]; /* free block map */
/* actually longer */
};
/*
* Turn file system block numbers into disk block addresses.
* This maps file system blocks to device size blocks.
*/
#define fsbtodb(fs, b) ((b) << (fs)->fs_fsbtodb)
#define dbtofsb(fs, b) ((b) >> (fs)->fs_fsbtodb)
/*
* Cylinder group macros to locate things in cylinder groups.
* They calc file system addresses of cylinder group data structures.
*/
#define cgbase(fs, c) ((daddr_t)((fs)->fs_fpg * (c)))
#define cgdmin(fs, c) (cgstart(fs, c) + (fs)->fs_dblkno) /* 1st data */
#define cgimin(fs, c) (cgstart(fs, c) + (fs)->fs_iblkno) /* inode blk */
#define cgsblock(fs, c) (cgstart(fs, c) + (fs)->fs_sblkno) /* super blk */
#define cgtod(fs, c) (cgstart(fs, c) + (fs)->fs_cblkno) /* cg block */
#define cgstart(fs, c) \
(cgbase(fs, c) + (fs)->fs_cgoffset * ((c) & ~((fs)->fs_cgmask)))
/*
* Macros for handling inode numbers:
* inode number to file system block offset.
* inode number to cylinder group number.
* inode number to file system block address.
*/
#define ino_to_cg(fs, x) ((x) / (fs)->fs_ipg)
#define ino_to_fsba(fs, x) \
((daddr_t)(cgimin(fs, ino_to_cg(fs, x)) + \
(blkstofrags((fs), (((x) % (fs)->fs_ipg) / INOPB(fs))))))
#define ino_to_fsbo(fs, x) ((x) % INOPB(fs))
/*
* Give cylinder group number for a file system block.
* Give frag block number in cylinder group for a file system block.
*/
#define dtog(fs, d) ((d) / (fs)->fs_fpg)
#define dtogd(fs, d) ((d) % (fs)->fs_fpg)
/*
* Extract the bits for a block from a map.
* Compute the cylinder and rotational position of a cyl block addr.
*/
#define blkmap(fs, map, loc) \
(((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag)))
#define cbtocylno(fs, bno) \
(fsbtodb(fs, bno) / (fs)->fs_spc)
#define cbtorpos(fs, bno) \
((fs)->fs_nrpos <= 1 ? 0 : \
(fsbtodb(fs, bno) % (fs)->fs_spc / (fs)->fs_nsect * (fs)->fs_trackskew + \
fsbtodb(fs, bno) % (fs)->fs_spc % (fs)->fs_nsect * (fs)->fs_interleave) % \
(fs)->fs_nsect * (fs)->fs_nrpos / (fs)->fs_npsect)
/*
* The following macros optimize certain frequently calculated
* quantities by using shifts and masks in place of divisions
* modulos and multiplications.
*/
#define blkoff(fs, loc) /* calculates (loc % fs->fs_bsize) */ \
((loc) & (fs)->fs_qbmask)
#define fragoff(fs, loc) /* calculates (loc % fs->fs_fsize) */ \
((loc) & (fs)->fs_qfmask)
#define lblktosize(fs, blk) /* calculates ((off_t)blk * fs->fs_bsize) */ \
((off_t)(blk) << (fs)->fs_bshift)
#define lblkno(fs, loc) /* calculates (loc / fs->fs_bsize) */ \
((loc) >> (fs)->fs_bshift)
#define numfrags(fs, loc) /* calculates (loc / fs->fs_fsize) */ \
((loc) >> (fs)->fs_fshift)
#define blkroundup(fs, size) /* calculates roundup(size, fs->fs_bsize) */ \
(((size) + (fs)->fs_qbmask) & (fs)->fs_bmask)
#define fragroundup(fs, size) /* calculates roundup(size, fs->fs_fsize) */ \
(((size) + (fs)->fs_qfmask) & (fs)->fs_fmask)
#define fragstoblks(fs, frags) /* calculates (frags / fs->fs_frag) */ \
((frags) >> (fs)->fs_fragshift)
#define blkstofrags(fs, blks) /* calculates (blks * fs->fs_frag) */ \
((blks) << (fs)->fs_fragshift)
#define fragnum(fs, fsb) /* calculates (fsb % fs->fs_frag) */ \
((fsb) & ((fs)->fs_frag - 1))
#define blknum(fs, fsb) /* calculates rounddown(fsb, fs->fs_frag) */ \
((fsb) &~ ((fs)->fs_frag - 1))
/*
* Determine the number of available frags given a
* percentage to hold in reserve.
*/
#define freespace(fs, percentreserved) \
(blkstofrags((fs), (fs)->fs_cstotal.cs_nbfree) + \
(fs)->fs_cstotal.cs_nffree - ((fs)->fs_dsize * (percentreserved) / 100))
/*
* Determining the size of a file block in the file system.
*/
#define blksize(fs, ip, lbn) \
(((lbn) >= NDADDR || DIP((ip), size) >= ((lbn) + 1) << (fs)->fs_bshift) \
? (fs)->fs_bsize \
: (fragroundup(fs, blkoff(fs, DIP((ip), size)))))
#define dblksize(fs, dip, lbn) \
(((lbn) >= NDADDR || (dip)->di_size >= ((lbn) + 1) << (fs)->fs_bshift) \
? (fs)->fs_bsize \
: (fragroundup(fs, blkoff(fs, (dip)->di_size))))
#define sblksize(fs, size, lbn) \
(((lbn) >= NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \
? (fs)->fs_bsize \
: (fragroundup(fs, blkoff(fs, (size)))))
/*
* Number of disk sectors per block/fragment; assumes DEV_BSIZE byte
* sector size.
*/
#define NSPB(fs) ((fs)->fs_nspf << (fs)->fs_fragshift)
#define NSPF(fs) ((fs)->fs_nspf)
/* Number of inodes per file system block (fs->fs_bsize) */
#define INOPB(fs) ((fs)->fs_inopb)
/* Number of inodes per file system fragment (fs->fs_fsize) */
#define INOPF(fs) ((fs)->fs_inopb >> (fs)->fs_fragshift)
/*
* Number of indirects in a file system block.
*/
#define NINDIR(fs) ((fs)->fs_nindir)
extern const int inside[], around[];
extern const u_char *fragtbl[];
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