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freebsd-nq/sys/ufs/ffs/fs.h
Xin LI a16baf37b9 The recomputation of file system summary at mount time can be a 
very slow process, especially for large file systems that is just
recovered from a crash.

Since the summary is already re-sync'ed every 30 second, we will
not lag behind too much after a crash.  With this consideration
in mind, it is more reasonable to transfer the responsibility to
background fsck, to reduce the delay after a crash.

Add a new sysctl variable, vfs.ffs.compute_summary_at_mount, to
control this behavior.  When set to nonzero, we will get the
"old" behavior, that the summary is computed immediately at mount
time.

Add five new sysctl variables to adjust ndir, nbfree, nifree,
nffree and numclusters respectively.  Teach fsck_ffs about these
API, however, intentionally not to check the existence, since
kernels without these sysctls must have recomputed the summary
and hence no adjustments are necessary.

This change has eliminated the usual tens of minutes of delay of
mounting large dirty volumes.

Reviewed by:	mckusick
MFC After:	1 week
2005-02-20 08:02:15 +00:00

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/*-
* 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.
* 4. 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 8.13 (Berkeley) 3/21/95
* $FreeBSD$
*/
#ifndef _UFS_FFS_FS_H_
#define _UFS_FFS_FS_H_
/*
* Each disk drive contains some number of filesystems.
* A filesystem consists of a number of cylinder groups.
* Each cylinder group has inodes and data.
*
* A filesystem 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 filesystem 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.
*
* Depending on the architecture and the media, the superblock may
* reside in any one of four places. For tiny media where every block
* counts, it is placed at the very front of the partition. Historically,
* UFS1 placed it 8K from the front to leave room for the disk label and
* a small bootstrap. For UFS2 it got moved to 64K from the front to leave
* room for the disk label and a bigger bootstrap, and for really piggy
* systems we check at 256K from the front if the first three fail. In
* all cases the size of the superblock will be SBLOCKSIZE. All values are
* given in byte-offset form, so they do not imply a sector size. The
* SBLOCKSEARCH specifies the order in which the locations should be searched.
*/
#define SBLOCK_FLOPPY 0
#define SBLOCK_UFS1 8192
#define SBLOCK_UFS2 65536
#define SBLOCK_PIGGY 262144
#define SBLOCKSIZE 8192
#define SBLOCKSEARCH \
{ SBLOCK_UFS2, SBLOCK_UFS1, SBLOCK_FLOPPY, SBLOCK_PIGGY, -1 }
/*
* Max number of fragments per block. This value is NOT tweakable.
*/
#define MAXFRAG 8
/*
* 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 filesystem 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 filesystem 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 filesystem 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 filesystem is maintained 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 a few
* 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. A fourth pointer, fs_active, is used when creating
* snapshots; it points to a bitmap of cylinder groups for which the
* free-block bitmap has changed since the snapshot operation began.
*/
#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 filesystem
* 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 filesystem
* 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. hence we use 10% as our
* default value. With 10% free space, fragmentation is not a
* problem, so we choose to optimize for time.
*/
#define MINFREE 8
#define DEFAULTOPT FS_OPTTIME
/*
* Grigoriy Orlov <gluk@ptci.ru> has done some extensive work to fine
* tune the layout preferences for directories within a filesystem.
* His algorithm 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 */
/*
* The maximum number of snapshot nodes that can be associated
* with each filesystem. This limit affects only the number of
* snapshot files that can be recorded within the superblock so
* that they can be found when the filesystem is mounted. However,
* maintaining too many will slow the filesystem performance, so
* having this limit is a good idea.
*/
#define FSMAXSNAP 20
/*
* Used to identify special blocks in snapshots:
*
* BLK_NOCOPY - A block that was unallocated at the time the snapshot
* was taken, hence does not need to be copied when written.
* BLK_SNAP - A block held by another snapshot that is not needed by this
* snapshot. When the other snapshot is freed, the BLK_SNAP entries
* are converted to BLK_NOCOPY. These are needed to allow fsck to
* identify blocks that are in use by other snapshots (which are
* expunged from this snapshot).
*/
#define BLK_NOCOPY ((ufs2_daddr_t)(1))
#define BLK_SNAP ((ufs2_daddr_t)(2))
/*
* Sysctl values for the fast filesystem.
*/
#define FFS_ADJ_REFCNT 1 /* adjust inode reference count */
#define FFS_ADJ_BLKCNT 2 /* adjust inode used block count */
#define FFS_BLK_FREE 3 /* free range of blocks in map */
#define FFS_DIR_FREE 4 /* free specified dir inodes in map */
#define FFS_FILE_FREE 5 /* free specified file inodes in map */
#define FFS_SET_FLAGS 6 /* set filesystem flags */
#define FFS_ADJ_NDIR 7 /* adjust number of directories */
#define FFS_ADJ_NBFREE 8 /* adjust number of free blocks */
#define FFS_ADJ_NIFREE 9 /* adjust number of free inodes */
#define FFS_ADJ_NFFREE 10 /* adjust number of free frags */
#define FFS_ADJ_NUMCLUSTERS 11 /* adjust number of free clusters */
#define FFS_MAXID 12 /* number of valid ffs ids */
/*
* Command structure passed in to the filesystem to adjust filesystem values.
*/
#define FFS_CMD_VERSION 0x19790518 /* version ID */
struct fsck_cmd {
int32_t version; /* version of command structure */
int32_t handle; /* reference to filesystem to be changed */
int64_t value; /* inode or block number to be affected */
int64_t size; /* amount or range to be adjusted */
int64_t spare; /* reserved for future use */
};
/*
* 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_numclusters; /* number of free clusters */
int64_t cs_spare[3]; /* future expansion */
};
/*
* Super block for an FFS filesystem.
*/
struct fs {
int32_t fs_firstfield; /* historic filesystem linked list, */
int32_t fs_unused_1; /* used for incore super blocks */
int32_t fs_sblkno; /* offset of super-block in filesys */
int32_t fs_cblkno; /* offset of cyl-block in filesys */
int32_t fs_iblkno; /* offset of inode-blocks in filesys */
int32_t fs_dblkno; /* offset of first data after cg */
int32_t fs_old_cgoffset; /* cylinder group offset in cylinder */
int32_t fs_old_cgmask; /* used to calc mod fs_ntrak */
int32_t fs_old_time; /* last time written */
int32_t fs_old_size; /* number of blocks in fs */
int32_t fs_old_dsize; /* number of data blocks in fs */
int32_t fs_ncg; /* number of cylinder groups */
int32_t fs_bsize; /* size of basic blocks in fs */
int32_t fs_fsize; /* size of frag blocks in fs */
int32_t fs_frag; /* number of frags in a block in fs */
/* these are configuration parameters */
int32_t fs_minfree; /* minimum percentage of free blocks */
int32_t fs_old_rotdelay; /* num of ms for optimal next block */
int32_t fs_old_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 number of frags */
/* these are configuration parameters */
int32_t fs_maxcontig; /* max number of contiguous blks */
int32_t fs_maxbpg; /* max number 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_spare1[2]; /* old fs_csmask */
/* old fs_csshift */
int32_t fs_nindir; /* value of NINDIR */
int32_t fs_inopb; /* value of INOPB */
int32_t fs_old_nspf; /* value of NSPF */
/* yet another configuration parameter */
int32_t fs_optim; /* optimization preference, see below */
int32_t fs_old_npsect; /* # sectors/track including spares */
int32_t fs_old_interleave; /* hardware sector interleave */
int32_t fs_old_trackskew; /* sector 0 skew, per track */
int32_t fs_id[2]; /* unique filesystem id */
/* sizes determined by number of cylinder groups and their sizes */
int32_t fs_old_csaddr; /* blk addr of cyl grp summary area */
int32_t fs_cssize; /* size of cyl grp summary area */
int32_t fs_cgsize; /* cylinder group size */
int32_t fs_spare2; /* old fs_ntrak */
int32_t fs_old_nsect; /* sectors per track */
int32_t fs_old_spc; /* sectors per cylinder */
int32_t fs_old_ncyl; /* cylinders in filesystem */
int32_t fs_old_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_old_cstotal; /* cylinder summary information */
/* these fields are cleared at mount time */
int8_t fs_fmod; /* super block modified flag */
int8_t fs_clean; /* filesystem is clean flag */
int8_t fs_ronly; /* mounted read-only flag */
int8_t fs_old_flags; /* old FS_ flags */
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; /* (u) # of contig. allocated dirs */
struct csum *fs_csp; /* (u) cg summary info buffer */
int32_t *fs_maxcluster; /* (u) max cluster in each cyl group */
u_int *fs_active; /* (u) used by snapshots to track fs */
int32_t fs_old_cpc; /* cyl per cycle in postbl */
int32_t fs_maxbsize; /* maximum blocking factor permitted */
int64_t fs_sparecon64[17]; /* old rotation block list head */
int64_t fs_sblockloc; /* byte offset of standard superblock */
struct csum_total fs_cstotal; /* (u) cylinder summary information */
ufs_time_t fs_time; /* last time written */
int64_t fs_size; /* number of blocks in fs */
int64_t fs_dsize; /* number of data blocks in fs */
ufs2_daddr_t fs_csaddr; /* blk addr of cyl grp summary area */
int64_t fs_pendingblocks; /* (u) blocks being freed */
int32_t fs_pendinginodes; /* (u) inodes being freed */
int32_t fs_snapinum[FSMAXSNAP];/* list of snapshot inode numbers */
int32_t fs_avgfilesize; /* expected average file size */
int32_t fs_avgfpdir; /* expected # of files per directory */
int32_t fs_save_cgsize; /* save real cg size to use fs_bsize */
int32_t fs_sparecon32[26]; /* reserved for future constants */
int32_t fs_flags; /* see FS_ flags below */
int32_t fs_contigsumsize; /* size of cluster summary array */
int32_t fs_maxsymlinklen; /* max length of an internal symlink */
int32_t fs_old_inodefmt; /* format of on-disk inodes */
u_int64_t fs_maxfilesize; /* maximum representable file size */
int64_t fs_qbmask; /* ~fs_bmask for use with 64-bit size */
int64_t fs_qfmask; /* ~fs_fmask for use with 64-bit size */
int32_t fs_state; /* validate fs_clean field */
int32_t fs_old_postblformat; /* format of positional layout tables */
int32_t fs_old_nrpos; /* number of rotational positions */
int32_t fs_spare5[2]; /* old fs_postbloff */
/* old fs_rotbloff */
int32_t fs_magic; /* magic number */
};
/* Sanity checking. */
#ifdef CTASSERT
CTASSERT(sizeof(struct fs) == 1376);
#endif
/*
* Filesystem identification
*/
#define FS_UFS1_MAGIC 0x011954 /* UFS1 fast filesystem magic number */
#define FS_UFS2_MAGIC 0x19540119 /* UFS2 fast filesystem magic number */
#define FS_BAD_MAGIC 0x19960408 /* UFS incomplete newfs magic number */
#define FS_OKAY 0x7c269d38 /* superblock checksum */
#define FS_42INODEFMT -1 /* 4.2BSD inode format */
#define FS_44INODEFMT 2 /* 4.4BSD inode format */
/*
* Preference for optimization.
*/
#define FS_OPTTIME 0 /* minimize allocation time */
#define FS_OPTSPACE 1 /* minimize disk fragmentation */
/*
* Filesystem flags.
*
* The FS_UNCLEAN flag is set by the kernel when the filesystem was
* mounted with fs_clean set to zero. The FS_DOSOFTDEP flag indicates
* that the filesystem should be managed by the soft updates code.
* Note that the FS_NEEDSFSCK flag is set and cleared only by the
* fsck utility. It is set when background fsck finds an unexpected
* inconsistency which requires a traditional foreground fsck to be
* run. Such inconsistencies should only be found after an uncorrectable
* disk error. A foreground fsck will clear the FS_NEEDSFSCK flag when
* it has successfully cleaned up the filesystem. The kernel uses this
* flag to enforce that inconsistent filesystems be mounted read-only.
* The FS_INDEXDIRS flag when set indicates that the kernel maintains
* on-disk auxiliary indexes (such as B-trees) for speeding directory
* accesses. Kernels that do not support auxiliary indicies clear the
* flag to indicate that the indicies need to be rebuilt (by fsck) before
* they can be used.
*
* FS_ACLS indicates that ACLs are administratively enabled for the
* file system, so they should be loaded from extended attributes,
* observed for access control purposes, and be administered by object
* owners. FS_MULTILABEL indicates that the TrustedBSD MAC Framework
* should attempt to back MAC labels into extended attributes on the
* file system rather than maintain a single mount label for all
* objects.
*/
#define FS_UNCLEAN 0x01 /* filesystem not clean at mount */
#define FS_DOSOFTDEP 0x02 /* filesystem using soft dependencies */
#define FS_NEEDSFSCK 0x04 /* filesystem needs sync fsck before mount */
#define FS_INDEXDIRS 0x08 /* kernel supports indexed directories */
#define FS_ACLS 0x10 /* file system has ACLs enabled */
#define FS_MULTILABEL 0x20 /* file system is MAC multi-label */
#define FS_FLAGS_UPDATED 0x80 /* flags have been moved to new location */
/*
* Macros to access bits in the fs_active array.
*/
#define ACTIVECGNUM(fs, cg) ((fs)->fs_active[(cg) / (NBBY * sizeof(int))])
#define ACTIVECGOFF(cg) (1 << ((cg) % (NBBY * sizeof(int))))
#define ACTIVESET(fs, cg) do { \
if ((fs)->fs_active) \
ACTIVECGNUM((fs), (cg)) |= ACTIVECGOFF((cg)); \
} while (0)
#define ACTIVECLEAR(fs, cg) do { \
if ((fs)->fs_active) \
ACTIVECGNUM((fs), (cg)) &= ~ACTIVECGOFF((cg)); \
} while (0)
/*
* 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) + \
/* old btotoff */ (fs)->fs_old_cpg * sizeof(int32_t) + \
/* old boff */ (fs)->fs_old_cpg * sizeof(u_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)))
/*
* The minimal number of cylinder groups that should be created.
*/
#define MINCYLGRPS 4
/*
* Convert cylinder group to base address of its global summary info.
*/
#define fs_cs(fs, indx) fs_csp[indx]
/*
* Cylinder group block for a filesystem.
*/
#define CG_MAGIC 0x090255
struct cg {
int32_t cg_firstfield; /* historic cyl groups linked list */
int32_t cg_magic; /* magic number */
int32_t cg_old_time; /* time last written */
int32_t cg_cgx; /* we are the cgx'th cylinder group */
int16_t cg_old_ncyl; /* number of cyl's this cg */
int16_t cg_old_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_old_btotoff; /* (int32) block totals per cylinder */
int32_t cg_old_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_niblk; /* number of inode blocks this cg */
int32_t cg_initediblk; /* last initialized inode */
int32_t cg_sparecon32[3]; /* reserved for future use */
ufs_time_t cg_time; /* time last written */
int64_t cg_sparecon64[3]; /* reserved for future use */
u_int8_t cg_space[1]; /* space for cylinder group maps */
/* actually longer */
};
/*
* Macros for access to cylinder group array structures
*/
#define cg_chkmagic(cgp) ((cgp)->cg_magic == CG_MAGIC)
#define cg_inosused(cgp) \
((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_iusedoff))
#define cg_blksfree(cgp) \
((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_freeoff))
#define cg_clustersfree(cgp) \
((u_int8_t *)((u_int8_t *)(cgp) + (cgp)->cg_clusteroff))
#define cg_clustersum(cgp) \
((int32_t *)((uintptr_t)(cgp) + (cgp)->cg_clustersumoff))
/*
* Turn filesystem block numbers into disk block addresses.
* This maps filesystem blocks to device size blocks.
*/
#define fsbtodb(fs, b) ((daddr_t)(b) << (fs)->fs_fsbtodb)
#define dbtofsb(fs, b) ((b) >> (fs)->fs_fsbtodb)
/*
* Cylinder group macros to locate things in cylinder groups.
* They calc filesystem addresses of cylinder group data structures.
*/
#define cgbase(fs, c) (((ufs2_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) \
((fs)->fs_magic == FS_UFS2_MAGIC ? cgbase(fs, c) : \
(cgbase(fs, c) + (fs)->fs_old_cgoffset * ((c) & ~((fs)->fs_old_cgmask))))
/*
* Macros for handling inode numbers:
* inode number to filesystem block offset.
* inode number to cylinder group number.
* inode number to filesystem block address.
*/
#define ino_to_cg(fs, x) ((x) / (fs)->fs_ipg)
#define ino_to_fsba(fs, x) \
((ufs2_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 filesystem block.
* Give cylinder group block number for a filesystem 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)))
/*
* 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 lfragtosize(fs, frag) /* calculates ((off_t)frag * fs->fs_fsize) */ \
(((off_t)(frag)) << (fs)->fs_fshift)
#define lblktosize(fs, blk) /* calculates ((off_t)blk * fs->fs_bsize) */ \
(((off_t)(blk)) << (fs)->fs_bshift)
/* Use this only when `blk' is known to be small, e.g., < NDADDR. */
#define smalllblktosize(fs, blk) /* calculates (blk * fs->fs_bsize) */ \
((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 - \
(((off_t)((fs)->fs_dsize)) * (percentreserved) / 100))
/*
* Determining the size of a file block in the filesystem.
*/
#define blksize(fs, ip, lbn) \
(((lbn) >= NDADDR || (ip)->i_size >= smalllblktosize(fs, (lbn) + 1)) \
? (fs)->fs_bsize \
: (fragroundup(fs, blkoff(fs, (ip)->i_size))))
#define sblksize(fs, size, lbn) \
(((lbn) >= NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \
? (fs)->fs_bsize \
: (fragroundup(fs, blkoff(fs, (size)))))
/*
* Number of inodes in a secondary storage block/fragment.
*/
#define INOPB(fs) ((fs)->fs_inopb)
#define INOPF(fs) ((fs)->fs_inopb >> (fs)->fs_fragshift)
/*
* Number of indirects in a filesystem block.
*/
#define NINDIR(fs) ((fs)->fs_nindir)
extern int inside[], around[];
extern u_char *fragtbl[];
#endif
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