4.4BSD snapshot (revision 8.1); add 1993 to copyright

[unix-history] / usr / src / sys / ufs / ffs / fs.h

diff --git a/usr/src/sys/ufs/ffs/fs.h b/usr/src/sys/ufs/ffs/fs.h
index 11b6f48..39ff1e6 100644 (file)
--- a/usr/src/sys/ufs/ffs/fs.h
+++ b/usr/src/sys/ufs/ffs/fs.h
@@ -1,9 +1,10 @@
 /*
 /*

- * Copyright (c) 1982 Regents of the University of California.
- * All rights reserved.  The Berkeley software License Agreement
- * specifies the terms and conditions for redistribution.
+ * Copyright (c) 1982, 1986, 1993
+ *     The Regents of the University of California.  All rights reserved.

  *
  *

- *     @(#)fs.h        6.4 (Berkeley) %G%
+ * %sccs.include.redist.c%
+ *
+ *     @(#)fs.h        8.1 (Berkeley) %G%

  */
 
 /*
  */
 
 /*


@@ -14,7 +15,7 @@
  * 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
  * 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 mkfs time and the critical
+ * 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.
  *
  * super-block data does not change, so the copies need not be
  * referenced further unless disaster strikes.
  *


@@ -28,11 +29,19 @@
  * the ``cgbase(fs, cg)'' macro.
  *
  * The first boot and super blocks are given in absolute disk addresses.
  * 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.
+ * The byte-offset forms are preferred, as they don't imply a sector size.

  */
 #define BBSIZE         8192
 #define SBSIZE         8192
  */
 #define BBSIZE         8192
 #define SBSIZE         8192

+#define        BBOFF           ((off_t)(0))
+#define        SBOFF           ((off_t)(BBOFF + BBSIZE))
+#define        BBOFF           ((off_t)(0))
+#define        SBOFF           ((off_t)(BBOFF + BBSIZE))
+#ifndef SECSIZE

 #define        BBLOCK          ((daddr_t)(0))
 #define        SBLOCK          ((daddr_t)(BBLOCK + BBSIZE / DEV_BSIZE))
 #define        BBLOCK          ((daddr_t)(0))
 #define        SBLOCK          ((daddr_t)(BBLOCK + BBSIZE / DEV_BSIZE))

+#endif SECSIZE

 
 /*
  * Addresses stored in inodes are capable of addressing fragments
 
 /*
  * Addresses stored in inodes are capable of addressing fragments


@@ -51,38 +60,7 @@
  *
  * The file system records space availability at the fragment level;
  * to determine block availability, aligned fragments are examined.
  *
  * The file system records space availability at the fragment level;
  * to determine block availability, aligned fragments are examined.

- *
- * The root inode is the root of the file system.
- * Inode 0 can't be used for normal purposes and
- * historically bad blocks were linked to inode 1,
- * thus the root inode is 2. (inode 1 is no longer used for
- * this purpose, however numerous dump tapes make this
- * assumption, so we are stuck with it)
- * The lost+found directory is given the next available
- * inode when it is created by ``mkfs''.
- */
-#define        ROOTINO         ((ino_t)2)      /* i number of all roots */
-#define LOSTFOUNDINO   (ROOTINO + 1)
-
-/*
- * Cylinder group related limits.
- *
- * For each cylinder we keep track of the availability of blocks at different
- * rotational positions, so that we can lay out the data to be picked
- * 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.
- */
-#define        NRPOS           8       /* number distinct rotational positions */
-
-/*
- * 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        MAXIPG          2048    /* max number inodes/cyl group */

 
 /*
  * MINBSIZE is the smallest allowable block size.
 
 /*
  * MINBSIZE is the smallest allowable block size.


@@ -90,14 +68,10 @@
  * 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.
  * 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.

- * MAXCPG is limited only to dimension an array in (struct cg);
- * it can be made larger as long as that structures size remains
- * within the bounds dictated by MINBSIZE.

  * Note that super blocks are always of size SBSIZE,
  * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE.
  */
 #define MINBSIZE       4096
  * Note that super blocks are always of size SBSIZE,
  * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE.
  */
 #define MINBSIZE       4096

-#define        MAXCPG          32      /* maximum fs_cpg */

 
 /*
  * The path name on which the file system is mounted is maintained
 
 /*
  * The path name on which the file system is mounted is maintained


@@ -129,9 +103,7 @@ struct csum {
 /*
  * Super block for a file system.
  */
 /*
  * Super block for a file system.
  */

-#define        FS_MAGIC        0x011954
-struct fs
-{
+struct fs {

        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 */
        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 */


@@ -168,12 +140,19 @@ struct    fs
        long    fs_nindir;              /* value of NINDIR */
        long    fs_inopb;               /* value of INOPB */
        long    fs_nspf;                /* value of NSPF */
        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 */
+/* yet another configuration parameter */
+       long    fs_optim;               /* optimization preference, see below */
+/* these fields are derived from the hardware */
+       long    fs_npsect;              /* # sectors/track including spares */
+       long    fs_interleave;          /* hardware sector interleave */
+       long    fs_trackskew;           /* sector 0 skew, per track */
+       long    fs_headswitch;          /* head switch time, usec */
+       long    fs_trkseek;             /* track-to-track seek, usec */

 /* 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 */
 /* 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 */
+/* these fields are derived from the hardware */

        long    fs_ntrak;               /* tracks per cylinder */
        long    fs_nsect;               /* sectors per track */
        long    fs_spc;                 /* sectors per cylinder */
        long    fs_ntrak;               /* tracks per cylinder */
        long    fs_nsect;               /* sectors per track */
        long    fs_spc;                 /* sectors per cylinder */


@@ -191,15 +170,57 @@ struct    fs
        char    fs_ronly;               /* mounted read-only flag */
        char    fs_flags;               /* currently unused flag */
        char    fs_fsmnt[MAXMNTLEN];    /* name mounted on */
        char    fs_ronly;               /* mounted read-only flag */
        char    fs_flags;               /* currently unused flag */
        char    fs_fsmnt[MAXMNTLEN];    /* name mounted on */

+       long    fs_dbsize;              /* hardware sector size */
+       long    fs_sparecon[31];        /* reserved for future constants */

 /* these fields retain the current block allocation info */
        long    fs_cgrotor;             /* last cg searched */
        struct  csum *fs_csp[MAXCSBUFS];/* list of fs_cs info buffers */
        long    fs_cpc;                 /* cyl per cycle in postbl */
 /* these fields retain the current block allocation info */
        long    fs_cgrotor;             /* last cg searched */
        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 */
+       short   fs_opostbl[16][8];      /* old rotation block list head */
+       long    fs_sparecon[51];        /* reserved for future constants */
+       long    fs_maxsymlinklen;       /* max length of an internal symlink */
+       long    fs_inodefmt;            /* format of on-disk inodes */
+       u_quad_t fs_maxfilesize;        /* maximum representable file size */
+       quad_t  fs_qbmask;              /* ~fs_bmask - for use with quad size */
+       quad_t  fs_qfmask;              /* ~fs_fmask - for use with quad size */
+       long    fs_state;               /* validate fs_clean field */
+       long    fs_postblformat;        /* format of positional layout tables */
+       long    fs_nrpos;               /* number of rotaional positions */
+       long    fs_postbloff;           /* (short) rotation block list head */
+       long    fs_rotbloff;            /* (u_char) blocks for each rotation */

        long    fs_magic;               /* magic number */
        long    fs_magic;               /* magic number */

-       u_char  fs_rotbl[1];            /* list of blocks for each rotation */
+       u_char  fs_space[1];            /* list of blocks for each rotation */

 /* actually longer */
 };
 /* actually longer */
 };

+/*
+ * Filesystem idetification
+ */
+#define        FS_MAGIC        0x011954        /* the 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 */
+/*
+ * Preference for optimization.
+ */
+#define FS_OPTTIME     0       /* minimize allocation time */
+#define FS_OPTSPACE    1       /* minimize disk fragmentation */
+
+/*
+ * 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_postbl(fs, cylno) \
+    (((fs)->fs_postblformat == FS_42POSTBLFMT) \
+    ? ((fs)->fs_opostbl[cylno]) \
+    : ((short *)((char *)(fs) + (fs)->fs_postbloff) + (cylno) * (fs)->fs_nrpos))
+#define fs_rotbl(fs) \
+    (((fs)->fs_postblformat == FS_42POSTBLFMT) \
+    ? ((fs)->fs_space) \
+    : ((u_char *)((char *)(fs) + (fs)->fs_rotbloff)))

 
 /*
  * Convert cylinder group to base address of its global summary info.
 
 /*
  * Convert cylinder group to base address of its global summary info.


@@ -209,24 +230,13 @@ struct    fs
 #define fs_cs(fs, indx) \
        fs_csp[(indx) >> (fs)->fs_csshift][(indx) & ~(fs)->fs_csmask]
 
 #define fs_cs(fs, indx) \
        fs_csp[(indx) >> (fs)->fs_csshift][(indx) & ~(fs)->fs_csmask]
 

-/*
- * MAXBPC bounds the size of the rotational layout tables and
- * is limited by the fact that the super block is of size SBSIZE.
- * The size of these tables is INVERSELY proportional to the block
- * size of the file system. It is aggravated by sector sizes that
- * are not powers of two, as this increases the number of cylinders
- * included before the rotational pattern repeats (fs_cpc).
- * Its size is derived from the number of bytes remaining in (struct fs)
- */
-#define        MAXBPC  (SBSIZE - sizeof (struct fs))
-

 /*
  * Cylinder group block for a file system.
  */
 #define        CG_MAGIC        0x090255
 struct cg {
        struct  cg *cg_link;            /* linked list of cyl groups */
 /*
  * Cylinder group block for a file system.
  */
 #define        CG_MAGIC        0x090255
 struct cg {
        struct  cg *cg_link;            /* linked list of cyl groups */

-       struct  cg *cg_rlink;           /*     used for incore cyl groups */
+       long    cg_magic;               /* magic number */

        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 */
        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 */


@@ -237,22 +247,61 @@ struct    cg {
        long    cg_frotor;              /* position of last used frag */
        long    cg_irotor;              /* position of last used inode */
        long    cg_frsum[MAXFRAG];      /* counts of available frags */
        long    cg_frotor;              /* position of last used frag */
        long    cg_irotor;              /* position of last used inode */
        long    cg_frsum[MAXFRAG];      /* counts of available frags */

-       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 */
-       long    cg_magic;               /* magic number */
-       u_char  cg_free[1];             /* free block map */
+       long    cg_btotoff;             /* (long) block totals per cylinder */
+       long    cg_boff;                /* (short) free block positions */
+       long    cg_iusedoff;            /* (char) used inode map */
+       long    cg_freeoff;             /* (u_char) free block map */
+       long    cg_nextfreeoff;         /* (u_char) next available space */
+       long    cg_sparecon[16];        /* reserved for future use */
+       u_char  cg_space[1];            /* space for cylinder group maps */

 /* actually longer */
 };
 /* actually longer */
 };

+/*
+ * Macros for access to cylinder group array structures
+ */
+#define cg_blktot(cgp) \
+    (((cgp)->cg_magic != CG_MAGIC) \
+    ? (((struct ocg *)(cgp))->cg_btot) \
+    : ((long *)((char *)(cgp) + (cgp)->cg_btotoff)))
+#define cg_blks(fs, cgp, cylno) \
+    (((cgp)->cg_magic != CG_MAGIC) \
+    ? (((struct ocg *)(cgp))->cg_b[cylno]) \
+    : ((short *)((char *)(cgp) + (cgp)->cg_boff) + (cylno) * (fs)->fs_nrpos))
+#define cg_inosused(cgp) \
+    (((cgp)->cg_magic != CG_MAGIC) \
+    ? (((struct ocg *)(cgp))->cg_iused) \
+    : ((char *)((char *)(cgp) + (cgp)->cg_iusedoff)))
+#define cg_blksfree(cgp) \
+    (((cgp)->cg_magic != CG_MAGIC) \
+    ? (((struct ocg *)(cgp))->cg_free) \
+    : ((u_char *)((char *)(cgp) + (cgp)->cg_freeoff)))
+#define cg_chkmagic(cgp) \
+    ((cgp)->cg_magic == CG_MAGIC || ((struct ocg *)(cgp))->cg_magic == CG_MAGIC)

 
 /*
 
 /*

- * MAXBPG bounds the number of blocks of data per cylinder group,
- * and is limited by the fact that cylinder groups are at most one block.
- * Its size is derived from the size of blocks and the (struct cg) size,
- * by the number of remaining bits.
+ * The following structure is defined
+ * for compatibility with old file systems.

  */
  */

-#define        MAXBPG(fs) \
-       (fragstoblks((fs), (NBBY * ((fs)->fs_bsize - (sizeof (struct cg))))))
+struct ocg {
+       struct  ocg *cg_link;           /* linked list of cyl groups */
+       struct  ocg *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 */
+       short   cg_niblk;               /* number of inode blocks this cg */
+       long    cg_ndblk;               /* number of data blocks this cg */
+       struct  csum cg_cs;             /* cylinder summary information */
+       long    cg_rotor;               /* position of last used block */
+       long    cg_frotor;              /* position of last used frag */
+       long    cg_irotor;              /* position of last used inode */
+       long    cg_frsum[8];            /* counts of available frags */
+       long    cg_btot[32];            /* block totals per cylinder */
+       short   cg_b[32][8];            /* positions of free blocks */
+       char    cg_iused[256];          /* used inode map */
+       long    cg_magic;               /* magic number */
+       u_char  cg_free[1];             /* free block map */
+/* actually longer */
+};

 
 /*
  * Turn file system block numbers into disk block addresses.
 
 /*
  * Turn file system block numbers into disk block addresses.


@@ -299,9 +348,11 @@ struct     cg {
 #define blkmap(fs, map, loc) \
     (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag)))
 #define cbtocylno(fs, bno) \
 #define blkmap(fs, map, loc) \
     (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag)))
 #define cbtocylno(fs, bno) \

-       ((bno) * NSPF(fs) / (fs)->fs_spc)
+    ((bno) * NSPF(fs) / (fs)->fs_spc)

 #define cbtorpos(fs, bno) \
 #define cbtorpos(fs, bno) \

-       ((bno) * NSPF(fs) % (fs)->fs_nsect * NRPOS / (fs)->fs_nsect)
+    (((bno) * NSPF(fs) % (fs)->fs_spc / (fs)->fs_nsect * (fs)->fs_trackskew + \
+     (bno) * NSPF(fs) % (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
 
 /*
  * The following macros optimize certain frequently calculated


@@ -309,17 +360,19 @@ struct    cg {
  * modulos and multiplications.
  */
 #define blkoff(fs, loc)                /* calculates (loc % fs->fs_bsize) */ \
  * modulos and multiplications.
  */
 #define blkoff(fs, loc)                /* calculates (loc % fs->fs_bsize) */ \

-       ((loc) & ~(fs)->fs_bmask)
+       ((loc) & (fs)->fs_qbmask)

 #define fragoff(fs, loc)       /* calculates (loc % fs->fs_fsize) */ \
 #define fragoff(fs, loc)       /* calculates (loc % fs->fs_fsize) */ \

-       ((loc) & ~(fs)->fs_fmask)
+       ((loc) & (fs)->fs_qfmask)
+#define lblktosize(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) */ \
 #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_bsize - 1) & (fs)->fs_bmask)
+       (((size) + (fs)->fs_qbmask) & (fs)->fs_bmask)

 #define fragroundup(fs, size)  /* calculates roundup(size, fs->fs_fsize) */ \
 #define fragroundup(fs, size)  /* calculates roundup(size, fs->fs_fsize) */ \

-       (((size) + (fs)->fs_fsize - 1) & (fs)->fs_fmask)
+       (((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) */ \
 #define fragstoblks(fs, frags) /* calculates (frags / fs->fs_frag) */ \
        ((frags) >> (fs)->fs_fragshift)
 #define blkstofrags(fs, blks)  /* calculates (blks * fs->fs_frag) */ \


@@ -366,7 +419,5 @@ struct      cg {
  */
 #define        NINDIR(fs)      ((fs)->fs_nindir)
 
  */
 #define        NINDIR(fs)      ((fs)->fs_nindir)
 

-#ifdef KERNEL
-struct fs *getfs();
-struct fs *mountfs();
-#endif
+extern int inside[], around[];
+extern u_char *fragtbl[];