/* $OpenBSD: fs.h,v 1.45 2024/02/03 18:51:58 beck 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 * addressable; 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. */ #define MAXFRAG 8 /* * 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 squid 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 */ u_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 */ u_int32_t fs_inopb; /* inodes per file system block */ int32_t fs_nspf; /* DEV_BSIZE sectors per frag */ /* yet another configuration parameter */ int32_t fs_optim; /* optimization preference, see below */ /* these fields are derived from the hardware */ int32_t fs_npsect; /* DEV_BSIZE sectors/track + spares */ int32_t fs_interleave; /* DEV_BSIZE 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; /* DEV_BSIZE sectors per track */ int32_t fs_spc; /* DEV_BSIZE 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 */ u_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 */ u_int32_t fs_pendinginodes; /* inodes in process of being freed */ u_int32_t fs_snapinum[FSMAXSNAP];/* space reserved for snapshots */ /* back to stuff that has been around a while */ u_int32_t fs_avgfilesize; /* expected average file size */ u_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 */ /* * 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 */ u_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 */ u_int32_t cg_ndblk; /* number of data blocks this cg */ struct csum cg_cs; /* cylinder summary information */ u_int32_t cg_rotor; /* position of last used block */ u_int32_t cg_frotor; /* position of last used frag */ u_int32_t cg_irotor; /* position of last used inode */ u_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 */ u_int32_t cg_iusedoff; /* (u_int8) used inode map */ u_int32_t cg_freeoff; /* (u_int8) free block map */ u_int32_t cg_nextfreeoff; /* (u_int8) next available space */ u_int32_t cg_clustersumoff; /* (u_int32) counts of avail clusters */ u_int32_t cg_clusteroff; /* (u_int8) free cluster map */ u_int32_t cg_nclusterblks; /* number of clusters this cg */ u_int32_t cg_ffs2_niblk; /* number of inode blocks this cg */ u_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 DEV_BSIZE (a.k.a. 512-byte) size disk * 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 cgdata(fs, c) (cgdmin(fs, c) + (fs)->fs_minfree) /* data zone */ #define cgmeta(fs, c) (cgdmin(fs, c)) /* meta data */ #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) \ ? (u_int64_t)(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) \ ? (u_int64_t)(fs)->fs_bsize \ : (fragroundup(fs, blkoff(fs, (dip)->di_size)))) #define sblksize(fs, size, lbn) \ (((lbn) >= NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \ ? (u_int64_t)(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) /* Maximum file size the kernel allows. * Even though ffs can handle files up to 16TB, we do limit the max file * to 2^31 pages to prevent overflow of a 32-bit unsigned int. The buffer * cache has its own checks but a little added paranoia never hurts. */ #define FS_KERNMAXFILESIZE(pgsiz, fs) ((u_int64_t)0x80000000 * \ MIN((pgsiz), (fs)->fs_bsize) - 1) extern const int inside[], around[]; extern const u_char *fragtbl[];
