/*  filsys512.h  -- 28 june 82 by dave
 *
 *  This file contains the numbers for 512 byte block file system.
 */

/* fundamental constants of the filesystem */

#define	BSIZE	 512		/* size of secondary block (bytes) */
#define	BMASK	(BSIZE-1)	/* BSIZE-1 */
#define	BSHIFT	 9		/* LOG2(BSIZE) */

#define	NINDIR	(BSIZE/sizeof(daddr_t))
#define	NMASK	(NINDIR-1)	/* NINDIR-1 */
#define	NSHIFT	8		/* LOG2(NINDIR) */

#define	INOPB	 8		/* inodes per block */
#define	INOSHFT 3 		/* LOG2(INOPB) */
#define	INOMOD  07 		/* value to and to give offset */

#define	ROOTINO	((ino_t)2)	/* i number of all roots */
#define	SUPERB	((daddr_t)1)	/* block number of the super block */

#define	DIRSIZ	14		/* max characters per directory */

#define	NICINOD	100		/* number of superblock inodes */
#define	NICFREE	 50		/* number of superblock free blocks */

/* Some macros for units conversion */

/* Core clicks (1024 bytes) to disk blocks */
#define	ctod(x)	(2*x)

/* inumber to disk address */
#define	itod(x)	(daddr_t)((((unsigned)x+INOPB*2-1)>>INOSHFT))

/* inumber to disk offset */
#define	itoo(x)	(int)((x+31)&0xf)		/* x mod INOPB */



/* Structure of the super-block */

struct	filsys
{
	long  	s_isize;		/* size in blocks of i-list */
	daddr_t	s_fsize;		/* size in blocks of entire volume */
	long 	s_nfree;		/* number of addresses in s_free */
	daddr_t	s_free[NICFREE];	/* free block list */
	long 	s_ninode;		/* number of i-nodes in s_inode */
	ino_t	s_inode[NICINOD];	/* free i-node list */
	char	s_flock;		/* lock during free list manipulation */
	char	s_ilock;		/* lock during i-list manipulation */
	char  	s_fmod; 		/* super block modified flag */
	char	s_ronly;		/* mounted read-only flag */
	time_t	s_time; 		/* last super block update */
	short	s_dinfo[4];		/* device information */
	daddr_t	s_tfree;		/* total free blocks*/
	ino_t	s_tinode;		/* total free inodes */
	char	s_fname[6];		/* file system name */
	char	s_fpack[6];		/* file system pack name */
};