1#ifndef _ADFS_FS_H
2#define _ADFS_FS_H
3
4#include <linux/types.h>
5
6/*
7 * Disc Record at disc address 0xc00
8 */
9struct adfs_discrecord {
10    __u8  log2secsize;
11    __u8  secspertrack;
12    __u8  heads;
13    __u8  density;
14    __u8  idlen;
15    __u8  log2bpmb;
16    __u8  skew;
17    __u8  bootoption;
18    __u8  lowsector;
19    __u8  nzones;
20    __u16 zone_spare;
21    __u32 root;
22    __u32 disc_size;
23    __u16 disc_id;
24    __u8  disc_name[10];
25    __u32 disc_type;
26    __u32 disc_size_high;
27    __u8  log2sharesize:4;
28    __u8  unused40:4;
29    __u8  big_flag:1;
30    __u8  unused41:1;
31    __u8  nzones_high;
32    __u32 format_version;
33    __u32 root_size;
34    __u8  unused52[60 - 52];
35};
36
37#define ADFS_DISCRECORD		(0xc00)
38#define ADFS_DR_OFFSET		(0x1c0)
39#define ADFS_DR_SIZE		 60
40#define ADFS_DR_SIZE_BITS	(ADFS_DR_SIZE << 3)
41#define ADFS_SUPER_MAGIC	 0xadf5
42
43#ifdef __KERNEL__
44/*
45 * Calculate the boot block checksum on an ADFS drive.  Note that this will
46 * appear to be correct if the sector contains all zeros, so also check that
47 * the disk size is non-zero!!!
48 */
49static inline int adfs_checkbblk(unsigned char *ptr)
50{
51	unsigned int result = 0;
52	unsigned char *p = ptr + 511;
53
54	do {
55	        result = (result & 0xff) + (result >> 8);
56        	result = result + *--p;
57	} while (p != ptr);
58
59	return (result & 0xff) != ptr[511];
60}
61
62#endif
63
64#endif
65