-/* Copyright (c) 1981 Regents of the University of California */
-
-/* fs.h 1.15 %G% */
+/* fs.h 6.1 83/07/29 */
/*
* Each disk drive contains some number of file systems.
*
* For file system fs, the offsets of the various blocks of interest
* are given in the super block as:
- * [fs->fs_bblkno] Boot sector
* [fs->fs_sblkno] Super-block
* [fs->fs_cblkno] Cylinder group block
* [fs->fs_iblkno] Inode blocks
*
* The first boot and super blocks are given in absolute disk addresses.
*/
-#define BBSIZE 1024
+#define BBSIZE 8192
#define SBSIZE 8192
#define BBLOCK ((daddr_t)(0))
#define SBLOCK ((daddr_t)(BBLOCK + BBSIZE / DEV_BSIZE))
#define ROOTINO ((ino_t)2) /* i number of all roots */
#define LOSTFOUNDINO (ROOTINO + 1)
-/*
- * 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 severe performance degredations will be observed if the
- * file system is run at greater than 90% full; thus the default
- * value of fs_minfree is 10%.
- *
- * Empirically the best trade-off between block fragmentation and
- * overall disk utilization at a loading of 90% comes with a
- * fragmentation of 4, thus the default fragment size is a fourth
- * of the block size.
- */
-#define MINFREE 10
-#define DESFRAG 4
-
-/*
- * Under current technology, most 300MB disks have 32 sectors and
- * 19 tracks, thus these are the defaults used for fs_nsect and
- * fs_ntrak respectively.
- */
-#define DFLNSECT 32
-#define DFLNTRAK 19
-
/*
* Cylinder group related limits.
*
* up with minimum rotational latency. NRPOS is the number of rotational
* positions which we distinguish. With NRPOS 8 the resolution of our
* summary information is 2ms for a typical 3600 rpm drive.
- *
- * ROTDELAY gives the minimum number of milliseconds to initiate
- * another disk transfer on the same cylinder. It is used in
- * determining the rotationally optimal layout for disk blocks
- * within a file; the default of fs_rotdelay is 2ms.
*/
#define NRPOS 8 /* number distinct rotational positions */
-#define ROTDELAY 2
/*
- * Each file system has a number of inodes statically allocated.
- * We allocate one inode slot per NBPI bytes, expecting this
- * to be far more than we will ever need.
- *
* MAXIPG bounds the number of inodes per cylinder group, and
* is needed only to keep the structure simpler by having the
* only a single variable size element (the free bit map).
*
* N.B.: MAXIPG must be a multiple of INOPB(fs).
*/
-#define NBPI 2048
#define MAXIPG 2048 /* max number inodes/cyl group */
/*
* and that MAXBSIZE must be >= MINBSIZE.
*/
#define MINBSIZE 4096
-#define DESCPG 16 /* desired fs_cpg */
#define MAXCPG 32 /* maximum fs_cpg */
/*
* 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.
+ * The limit on the amount of summary information per file system
+ * is defined by MAXCSBUFS. It is currently parameterized for a
+ * maximum of two million cylinders.
*/
-#define MAXMNTLEN 34
+#define MAXMNTLEN 512
+#define MAXCSBUFS 32
/*
* Per cylinder group information; summarized in blocks allocated
/*
* Super block for a file system.
*/
-#define FS_MAGIC 0x110854
+#define FS_MAGIC 0x011954
struct fs
{
- long fs_magic; /* magic number */
- daddr_t fs_bblkno; /* abs addr of boot-block in filesys */
- daddr_t fs_sblkno; /* abs addr of super-block in filesys */
+ struct fs *fs_link; /* linked list of file systems */
+ struct fs *fs_rlink; /* used for incore super blocks */
+ daddr_t fs_sblkno; /* addr of super-block in filesys */
daddr_t fs_cblkno; /* offset of cyl-block in filesys */
daddr_t fs_iblkno; /* offset of inode-blocks in filesys */
- daddr_t fs_dblkno; /* offset of data-blocks in filesys */
+ daddr_t fs_dblkno; /* offset of first data after cg */
+ long fs_cgoffset; /* cylinder group offset in cylinder */
+ long fs_cgmask; /* used to calc mod fs_ntrak */
time_t fs_time; /* last time written */
long fs_size; /* number of blocks in fs */
long fs_dsize; /* number of data blocks in fs */
long fs_ncg; /* number of cylinder groups */
long fs_bsize; /* size of basic blocks in fs */
long fs_fsize; /* size of frag blocks in fs */
- short fs_frag; /* number of frags in a block in fs */
- short fs_minfree; /* minimum percentage of free blocks */
- short fs_rotdelay; /* num of ms for optimal next block */
- short fs_rps; /* disk revolutions per second */
+ long fs_frag; /* number of frags in a block in fs */
+/* these are configuration parameters */
+ long fs_minfree; /* minimum percentage of free blocks */
+ long fs_rotdelay; /* num of ms for optimal next block */
+ long fs_rps; /* disk revolutions per second */
+/* these fields can be computed from the others */
long fs_bmask; /* ``blkoff'' calc of blk offsets */
long fs_fmask; /* ``fragoff'' calc of frag offsets */
- short fs_bshift; /* ``lblkno'' calc of logical blkno */
- short fs_fshift; /* ``numfrags'' calc number of frags */
+ long fs_bshift; /* ``lblkno'' calc of logical blkno */
+ long fs_fshift; /* ``numfrags'' calc number of frags */
+/* these are configuration parameters */
+ long fs_maxcontig; /* max number of contiguous blks */
+ long fs_maxbpg; /* max number of blks per cyl group */
+/* these fields can be computed from the others */
+ long fs_fragshift; /* block to frag shift */
+ long fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */
+ long fs_sbsize; /* actual size of super block */
+ long fs_csmask; /* csum block offset */
+ long fs_csshift; /* csum block number */
+ long fs_nindir; /* value of NINDIR */
+ long fs_inopb; /* value of INOPB */
+ long fs_nspf; /* value of NSPF */
+ long fs_sparecon[6]; /* reserved for future constants */
/* sizes determined by number of cylinder groups and their sizes */
daddr_t fs_csaddr; /* blk addr of cyl grp summary area */
long fs_cssize; /* size of cyl grp summary area */
long fs_cgsize; /* cylinder group size */
/* these fields should be derived from the hardware */
- short fs_ntrak; /* tracks per cylinder */
- short fs_nsect; /* sectors per track */
+ long fs_ntrak; /* tracks per cylinder */
+ long fs_nsect; /* sectors per track */
long fs_spc; /* sectors per cylinder */
/* this comes from the disk driver partitioning */
long fs_ncyl; /* cylinders in file system */
/* these fields can be computed from the others */
- short fs_cpg; /* cylinders per group */
- short fs_ipg; /* inodes per group */
+ long fs_cpg; /* cylinders per group */
+ long fs_ipg; /* inodes per group */
long fs_fpg; /* blocks per group * fs_frag */
/* this data must be re-computed after crashes */
struct csum fs_cstotal; /* cylinder summary information */
/* these fields are cleared at mount time */
char fs_fmod; /* super block modified flag */
+ char fs_clean; /* file system is clean flag */
char fs_ronly; /* mounted read-only flag */
+ char fs_flags; /* currently unused flag */
char fs_fsmnt[MAXMNTLEN]; /* name mounted on */
/* these fields retain the current block allocation info */
long fs_cgrotor; /* last cg searched */
- struct csum *fs_csp[NBUF / 2]; /* list of fs_cs info buffers */
- short fs_cpc; /* cyl per cycle in postbl */
+ struct csum *fs_csp[MAXCSBUFS];/* list of fs_cs info buffers */
+ long fs_cpc; /* cyl per cycle in postbl */
short fs_postbl[MAXCPG][NRPOS];/* head of blocks for each rotation */
+ long fs_magic; /* magic number */
u_char fs_rotbl[1]; /* list of blocks for each rotation */
/* actually longer */
};
* N.B. This macro assumes that sizeof(struct csum) is a power of two.
*/
#define fs_cs(fs, indx) \
- fs_csp[(indx) / ((fs)->fs_bsize / sizeof(struct csum))] \
- [(indx) % ((fs)->fs_bsize / sizeof(struct csum))]
+ fs_csp[(indx) >> (fs)->fs_csshift][(indx) & ~(fs)->fs_csmask]
/*
* MAXBPC bounds the size of the rotational layout tables and
/*
* Cylinder group block for a file system.
*/
-#define CG_MAGIC 0x092752
+#define CG_MAGIC 0x090255
struct cg {
- long cg_magic; /* magic number */
+ struct cg *cg_link; /* linked list of cyl groups */
+ struct cg *cg_rlink; /* used for incore cyl groups */
time_t cg_time; /* time last written */
long cg_cgx; /* we are the cgx'th cylinder group */
short cg_ncyl; /* number of cyl's this cg */
long cg_btot[MAXCPG]; /* block totals per cylinder */
short cg_b[MAXCPG][NRPOS]; /* positions of free blocks */
char cg_iused[MAXIPG/NBBY]; /* used inode map */
- char cg_free[1]; /* free block map */
+ long cg_magic; /* magic number */
+ u_char cg_free[1]; /* free block map */
/* actually longer */
};
* by the number of remaining bits.
*/
#define MAXBPG(fs) \
- (NBBY * ((fs)->fs_bsize - (sizeof (struct cg))) / (fs)->fs_frag)
+ (fragstoblks((fs), (NBBY * ((fs)->fs_bsize - (sizeof (struct cg))))))
/*
* 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_fsize / DEV_BSIZE))
-#define dbtofsb(fs, b) ((b) / ((fs)->fs_fsize / DEV_BSIZE))
+#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.
- *
- * Cylinder group to disk block address of spare boot block
- * and super block.
- * Note that these are in absolute addresses, and can NOT
- * in general be expressable in terms of file system addresses.
+ * They calc file system addresses of cylinder group data structures.
*/
-#define cgbblock(fs, c) (fsbtodb(fs, cgbase(fs, c)) + (fs)->fs_bblkno)
-#define cgsblock(fs, c) (fsbtodb(fs, cgbase(fs, c)) + (fs)->fs_sblkno)
-
-/*
- * File system addresses of cylinder group data structures.
- */
-#define cgbase(fs, c) ((daddr_t)((fs)->fs_fpg * (c))) /* base addr */
-#define cgtod(fs, c) (cgbase(fs, c) + (fs)->fs_cblkno) /* cg block */
-#define cgimin(fs, c) (cgbase(fs, c) + (fs)->fs_iblkno) /* inode blk */
-#define cgdmin(fs, c) (cgbase(fs, c) + (fs)->fs_dblkno) /* 1st data */
+#define cgbase(fs, c) ((daddr_t)((fs)->fs_fpg * (c)))
+#define cgstart(fs, c) \
+ (cgbase(fs, c) + (fs)->fs_cgoffset * ((c) & ~((fs)->fs_cgmask)))
+#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 cgimin(fs, c) (cgstart(fs, c) + (fs)->fs_iblkno) /* inode blk */
+#define cgdmin(fs, c) (cgstart(fs, c) + (fs)->fs_dblkno) /* 1st data */
/*
* Macros for handling inode numbers:
#define itog(fs, x) ((x) / (fs)->fs_ipg)
#define itod(fs, x) \
((daddr_t)(cgimin(fs, itog(fs, x)) + \
- (x) % (fs)->fs_ipg / INOPB(fs) * (fs)->fs_frag))
+ (blkstofrags((fs), (((x) % (fs)->fs_ipg) / INOPB(fs))))))
/*
* Give cylinder group number for a file system block.
(((size) + (fs)->fs_bsize - 1) & (fs)->fs_bmask)
#define fragroundup(fs, size) /* calculates roundup(size, fs->fs_fsize) */ \
(((size) + (fs)->fs_fsize - 1) & (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)
+
+/*
+ * 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 || (ip)->i_size >= ((lbn) + 1) * (fs)->fs_bsize) \
+ (((lbn) >= NDADDR || (ip)->i_size >= ((lbn) + 1) << (fs)->fs_bshift) \
? (fs)->fs_bsize \
: (fragroundup(fs, blkoff(fs, (ip)->i_size))))
#define dblksize(fs, dip, lbn) \
- (((lbn) >= NDADDR || (dip)->di_size >= ((lbn) + 1) * (fs)->fs_bsize) \
+ (((lbn) >= NDADDR || (dip)->di_size >= ((lbn) + 1) << (fs)->fs_bshift) \
? (fs)->fs_bsize \
: (fragroundup(fs, blkoff(fs, (dip)->di_size))))
/*
* Number of disk sectors per block; assumes DEV_BSIZE byte sector size.
*/
-#define NSPB(fs) ((fs)->fs_bsize / DEV_BSIZE)
-#define NSPF(fs) ((fs)->fs_fsize / DEV_BSIZE)
+#define NSPB(fs) ((fs)->fs_nspf << (fs)->fs_fragshift)
+#define NSPF(fs) ((fs)->fs_nspf)
/*
* INOPB is the number of inodes in a secondary storage block.
*/
-#define INOPB(fs) ((fs)->fs_bsize / sizeof (struct dinode))
-#define INOPF(fs) ((fs)->fs_fsize / sizeof (struct dinode))
+#define INOPB(fs) ((fs)->fs_inopb)
+#define INOPF(fs) ((fs)->fs_inopb >> (fs)->fs_fragshift)
/*
* NINDIR is the number of indirects in a file system block.
*/
-#define NINDIR(fs) ((fs)->fs_bsize / sizeof (daddr_t))
+#define NINDIR(fs) ((fs)->fs_nindir)
#ifdef KERNEL
struct fs *getfs();
+struct fs *mountfs();
#endif