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

/*-
* Copyright (c) 1991 The Regents of the University of California.
* All rights reserved.
*
* %sccs.include.redist.c%
*
*      @(#)lfs.h       7.12 (Berkeley) %G%
*/

#define LFS_LABELPAD    8192            /* LFS label size */
#define LFS_SBPAD       8192            /* LFS superblock size */
#define MAXMNTLEN       512             /* XXX move from fs.h to mount.h */

/* On-disk and in-memory checkpoint segment usage structure. */
typedef struct segusage SEGUSE;
struct segusage {
       u_long  su_nbytes;              /* number of live bytes */
       u_long  su_lastmod;             /* SEGUSE last modified timestamp */
#define SEGUSE_ACTIVE           0x1     /* segment is currently being written */
#define SEGUSE_DIRTY            0x2     /* segment has data in it */
#define SEGUSE_SUPERBLOCK       0x4     /* segment contains a superblock */
       u_long  su_flags;
};

#define SEGTABSIZE_SU(fs) \
       (((fs)->lfs_nseg * sizeof(SEGUSE) + \
       ((fs)->lfs_bsize - 1)) >> (fs)->lfs_bshift)

/* On-disk file information.  One per file with data blocks in the segment. */
typedef struct finfo FINFO;
struct finfo {
       u_long  fi_nblocks;             /* number of blocks */
       u_long  fi_version;             /* version number */
       u_long  fi_ino;                 /* inode number */
       long    fi_blocks[1];           /* array of logical block numbers */
};

/* On-disk and in-memory super block. */
struct lfs {
#define LFS_MAGIC       0x070162
       u_long  lfs_magic;              /* magic number */
#define LFS_VERSION     1
       u_long  lfs_version;            /* version number */

       u_long  lfs_size;               /* number of blocks in fs */
       u_long  lfs_ssize;              /* number of blocks per segment */
       u_long  lfs_dsize;              /* number of data blocks in fs */
       u_long  lfs_bsize;              /* size of basic blocks in fs */
       u_long  lfs_fsize;              /* size of frag blocks in fs */
       u_long  lfs_frag;               /* number of frags in a block in fs */

/* Checkpoint region. */
       ino_t   lfs_free;               /* start of the free list */
       u_long  lfs_bfree;              /* number of free blocks */
       u_long  lfs_nfiles;             /* number of allocated inodes */
       daddr_t lfs_idaddr;             /* inode file disk address */
       ino_t   lfs_ifile;              /* inode file inode number */
       daddr_t lfs_lastseg;            /* address of last segment written */
       daddr_t lfs_nextseg;            /* address of next segment to write */
       daddr_t lfs_curseg;             /* current segment being written */
       daddr_t lfs_offset;             /* offset in curseg for next partial */
       u_long  lfs_tstamp;             /* time stamp */

/* These are configuration parameters. */
       u_long  lfs_minfree;            /* minimum percentage of free blocks */

/* These fields can be computed from the others. */
       u_long  lfs_dbpseg;             /* disk blocks per segment */
       u_long  lfs_inopb;              /* inodes per block */
       u_long  lfs_ifpb;               /* IFILE entries per block */
       u_long  lfs_sepb;               /* SEGUSE entries per block */
       u_long  lfs_nindir;             /* indirect pointers per block */
       u_long  lfs_nseg;               /* number of segments */
       u_long  lfs_nspf;               /* number of sectors per fragment */
       u_long  lfs_cleansz;            /* cleaner info size in blocks */
       u_long  lfs_segtabsz;           /* segment table size in blocks */

       u_long  lfs_segmask;            /* calculate offset within a segment */
       u_long  lfs_segshift;           /* fast mult/div for segments */
       u_long  lfs_bmask;              /* calc block offset from file offset */
       u_long  lfs_bshift;             /* calc block number from file offset */
       u_long  lfs_ffmask;             /* calc frag offset from file offset */
       u_long  lfs_ffshift;            /* fast mult/div for frag from file */
       u_long  lfs_fbmask;             /* calc frag offset from block offset */
       u_long  lfs_fbshift;            /* fast mult/div for frag from block */
       u_long  lfs_fsbtodb;            /* fsbtodb and dbtofsb shift constant */

#define LFS_MIN_SBINTERVAL      5       /* minimum superblock segment spacing */
#define LFS_MAXNUMSB            10      /* superblock disk offsets */
       daddr_t lfs_sboffs[LFS_MAXNUMSB];

/* These fields are set at mount time and are meaningless on disk. */
       struct  vnode *lfs_ivnode;      /* vnode for the ifile */
       SEGUSE  *lfs_segtab;            /* in-memory segment usage table */
                                       /* XXX NOT USED */
       void    *XXXlfs_seglist;        /* list of segments being written */
       u_long  lfs_iocount;            /* number of ios pending */
       u_char  lfs_fmod;               /* super block modified flag */
       u_char  lfs_clean;              /* file system is clean flag */
       u_char  lfs_ronly;              /* mounted read-only flag */
       u_char  lfs_flags;              /* currently unused flag */
       u_char  lfs_fsmnt[MAXMNTLEN];   /* name mounted on */
       u_char  pad[3];                 /* long-align */

/* Checksum; valid on disk. */
       u_long  lfs_cksum;              /* checksum for superblock checking */
};

/*
* Inode 0 is the out-of-band inode number, inode 1 is the inode number for
* the IFILE, the root inode is 2 and the lost+found inode is 3.
*/

/* Fixed inode numbers. */
#define LFS_UNUSED_INUM 0               /* out of band inode number */
#define LFS_IFILE_INUM  1               /* IFILE inode number */
#define LOSTFOUNDINO    3               /* lost+found inode number */
#define LFS_FIRST_INUM  4               /* first free inode number */

/*
* Used to access the first spare of the dinode which we use to store
* the ifile number so we can identify them
*/
#define di_inum di_spare[0]

/* Address calculations for metadata located in the inode */
#define S_INDIR(fs)     -NDADDR
#define D_INDIR(fs)     (S_INDIR(fs) - NINDIR(fs) - 1)
#define T_INDIR(fs)     (D_INDIR(fs) - NINDIR(fs) * NINDIR(fs) - 1)

/* Structure used to pass around logical block paths. */
typedef struct _indir {
       long    in_lbn;                 /* logical block number */
       int     in_off;                 /* offset in buffer */
} INDIR;

/* Unassigned disk address. */
#define UNASSIGNED      -1

typedef struct ifile IFILE;
struct ifile {
       u_long  if_version;             /* inode version number */
#define LFS_UNUSED_DADDR        0       /* out-of-band daddr */
       daddr_t if_daddr;               /* inode disk address */
       ino_t   if_nextfree;            /* next-unallocated inode */
};

/*
* Cleaner information structure.  This resides in the ifile and is used
* to pass information between the cleaner and the kernel.
*/
typedef struct _cleanerinfo {
       u_long  clean;                  /* K: number of clean segments */
       u_long  dirty;                  /* K: number of dirty segments */
} CLEANERINFO;

#define CLEANSIZE_SU(fs) \
       ((sizeof(CLEANERINFO) + (fs)->lfs_bsize - 1) >> (fs)->lfs_bshift)

/*
* All summary blocks are the same size, so we can always read a summary
* block easily from a segment.
*/
#define LFS_SUMMARY_SIZE        512

/* On-disk segment summary information */
typedef struct segsum SEGSUM;
struct segsum {
       u_long  ss_sumsum;              /* check sum of summary block */
       u_long  ss_datasum;             /* check sum of data */
       daddr_t ss_next;                /* next segment */
       u_long  ss_create;              /* creation time stamp */
       u_long  ss_nfinfo;              /* number of file info structures */
       u_long  ss_ninos;               /* number of inodes in summary */
       /* FINFO's and inode daddr's... */
};

/* NINDIR is the number of indirects in a file system block. */
#define NINDIR(fs)      ((fs)->lfs_nindir)

/* INOPB is the number of inodes in a secondary storage block. */
#define INOPB(fs)       ((fs)->lfs_inopb)

#define blksize(fs)             ((fs)->lfs_bsize)
#define blkoff(fs, loc)         ((loc) & (fs)->lfs_bmask)
#define fsbtodb(fs, b)          ((b) << (fs)->lfs_fsbtodb)
#define lblkno(fs, loc)         ((loc) >> (fs)->lfs_bshift)
#define lblktosize(fs, blk)     ((blk) << (fs)->lfs_bshift)
#define numfrags(fs, loc)       /* calculates (loc / fs->fs_fsize) */ \
       ((loc) >> (fs)->lfs_bshift)

#define datosn(fs, daddr)       /* disk address to segment number */ \
       (((daddr) - (fs)->lfs_sboffs[0]) / fsbtodb((fs), (fs)->lfs_ssize))
#define sntoda(fs, sn)          /* segment number to disk address */ \
       ((daddr_t)((sn) * ((fs)->lfs_ssize << (fs)->lfs_fsbtodb) + \
           (fs)->lfs_sboffs[0]))

/* Read in the block with the cleaner info from the ifile. */
#define LFS_CLEANERINFO(CP, F, BP) { \
       VTOI((F)->lfs_ivnode)->i_flag |= IACC; \
       if (bread((F)->lfs_ivnode, (daddr_t)0, (F)->lfs_bsize, NOCRED, &(BP))) \
               panic("lfs: ifile read"); \
       (CP) = (CLEANERINFO *)(BP)->b_un.b_addr; \
}

/* Read in the block with a specific inode from the ifile. */
#define LFS_IENTRY(IP, F, IN, BP) { \
       VTOI((F)->lfs_ivnode)->i_flag |= IACC; \
       if (bread((F)->lfs_ivnode, \
           (IN) / (F)->lfs_ifpb + (F)->lfs_cleansz + (F)->lfs_segtabsz, \
           (F)->lfs_bsize, NOCRED, &(BP))) \
               panic("lfs: ifile read"); \
       (IP) = (IFILE *)(BP)->b_un.b_addr + (IN) % (F)->lfs_ifpb; \
}

/* Read in the block with a specific segment usage entry from the ifile. */
#define LFS_SEGENTRY(SP, F, IN, BP) { \
       VTOI((F)->lfs_ivnode)->i_flag |= IACC; \
       if (bread((F)->lfs_ivnode, (IN) / (F)->lfs_sepb + (F)->lfs_cleansz, \
           (F)->lfs_bsize, NOCRED, &(BP))) \
               panic("lfs: ifile read"); \
       (SP) = (SEGUSE *)(BP)->b_un.b_addr + (IN) % (F)->lfs_sepb; \
}

/* Write a block and update the inode change times. */
#define LFS_UBWRITE(BP) { \
       VTOI((BP)->b_vp)->i_flag |= ICHG | IUPD; \
       lfs_bwrite(BP); \
}

/*
* Structures used by lfs_bmapv and lfs_markv to communicate information
* about inodes and data blocks.
*/
typedef struct block_info {
       ino_t   bi_inode;               /* inode # */
       off_t   bi_lbn;                 /* logical block w/in file */
       daddr_t bi_daddr;               /* disk address of block */
       time_t  bi_segcreate;           /* origin segment create time */
       void    *bi_bp;                 /* data buffer */
} BLOCK_INFO;

typedef struct inode_info {
       ino_t   ii_inode;               /* inode # */
       daddr_t ii_daddr;               /* disk address of block */
       time_t  ii_segcreate;           /* origin segment create time */
       struct dinode *ii_dinode;       /* data buffer */
} INODE_INFO;