xref: /minix3/minix/usr.sbin/mkfs.mfs/v2/const.h (revision 433d6423c39e34ec4b79c950597bb2d236f886be)
1 #ifndef _MKFS_MFS_CONST_H__
2 #define _MKFS_MFS_CONST_H__
3 
4 /* Tables sizes */
5 #define NR_DZONES       7	/* # direct zone numbers in a V2 inode */
6 #define NR_TZONES      10	/* total # zone numbers in a V2 inode */
7 
8 /* Blocks are of a fixed size */
9 #define MFS_STATIC_BLOCK_SIZE	1024
10 
11 #define SUPER_BLOCK_BYTES  MFS_STATIC_BLOCK_SIZE	/* 1 block */
12 
13 /* The type of sizeof may be (unsigned) long.  Use the following macro for
14  * taking the sizes of small objects so that there are no surprises like
15  * (small) long constants being passed to routines expecting an int.
16  */
17 #define usizeof(t) ((unsigned) sizeof(t))
18 
19 /* File system types: magic number contained in super-block. */
20 #define SUPER_V2	0x2468	/* magic # for V2 file systems */
21 #define SUPER_MAGIC	SUPER_V2
22 
23 /* Miscellaneous constants */
24 #define SU_UID		((uid_t) 0)	/* super_user's uid_t */
25 #define SECTOR_SIZE	512
26 
27 #define BOOT_BLOCK	((block_t) 0)	/* block number of boot block */
28 #define SUPER_BLOCK	((block_t) 1)	/* block number of super block */
29 #define START_BLOCK	((block_t) 2)	/* first block of FS (not counting SB) */
30 
31 #define ROOT_INODE	((ino_t) 1)	/* inode number for root directory */
32 
33 /* Derived sizes pertaining to the file system. */
34 #define FS_BITMAP_CHUNKS(b) ((b)/usizeof (uint32_t))/* # map chunks/blk   */
35 #define FS_BITCHUNK_BITS		(usizeof(uint32_t) * CHAR_BIT)
36 #define FS_BITS_PER_BLOCK(b)	(FS_BITMAP_CHUNKS(b) * FS_BITCHUNK_BITS)
37 
38 #define ZONE_NUM_SIZE		usizeof (zone_t)  /* # bytes in zone */
39 #define INODE_SIZE		usizeof (struct inode)  /* bytes in dsk ino */
40 #define INODES_PER_BLOCK(b)	((b)/INODE_SIZE)  /* # V2 dsk inodes/blk */
41 #define INDIRECTS(b)		((b)/ZONE_NUM_SIZE)  /* # zones/indir block */
42 
43 #define DIR_ENTRY_SIZE		usizeof(struct direct) /* # bytes/dir entry */
44 #define NR_DIR_ENTRIES(b)	((b)/DIR_ENTRY_SIZE)  /* # dir entries/blk  */
45 #endif
46