ufs_fs.h

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	void 	*fs_ocsp[NOCSPTRS];	/* padding; was list of fs_cs buffers */
	uint8_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 */
	unsigned int *fs_active;	/* 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;	/* 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;	/* blocks in process of being freed */
	int32_t	 fs_pendinginodes;	/* inodes in process of 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 */
	uint64_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))))

/*
 * 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(uint16_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;		/* (uint16) free block positions */
	int32_t	 cg_iusedoff;		/* (uint8) used inode map */
	int32_t	 cg_freeoff;		/* (uint8) free block map */
	int32_t	 cg_nextfreeoff;	/* (uint8) next available space */
	int32_t	 cg_clustersumoff;	/* (uint32) counts of avail clusters */
	int32_t	 cg_clusteroff;		/* (uint8) 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 */
	uint8_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) \
    ((uint8_t *)((uint8_t *)(cgp) + (cgp)->cg_iusedoff))
#define cg_blksfree(cgp) \
    ((uint8_t *)((uint8_t *)(cgp) + (cgp)->cg_freeoff))
#define cg_clustersfree(cgp) \
    ((uint8_t *)((uint8_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)	((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 char *fragtbl[];

struct ufs_dirent {
	uint32_t d_fileno;		/* file number of entry */
	uint16_t d_reclen;		/* length of this record */
	uint8_t  d_type; 		/* file type, see below */
	uint8_t  d_namlen;		/* length of string in d_name */
#define	MAXNAMLEN	255
	char	d_name[MAXNAMLEN + 1];	/* name must be no longer than this */
};

/*
 * File types
 */
#define	DT_UNKNOWN	 0
#define	DT_FIFO		 1
#define	DT_CHR		 2
#define	DT_DIR		 4
#define	DT_BLK		 6
#define	DT_REG		 8
#define	DT_LNK		10
#define	DT_SOCK		12
#define	DT_WHT		14

/* XXX: We hardcode BSIZE and BSIZE_SHIFT here. fsys_ffs seems to do the same,
 *      so we should get away with it :-) */
#define DEV_BSIZE	512
#define DEV_BSHIFT 	9		/* 2**9 = 512 */
#define MAXBSIZE	8192

typedef unsigned int ino_t;

#endif