1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ADFS_FS_H
3#define _ADFS_FS_H
4
5#include <uapi/linux/adfs_fs.h>
6
7/*
8 * Calculate the boot block checksum on an ADFS drive. Note that this will
9 * appear to be correct if the sector contains all zeros, so also check that
10 * the disk size is non-zero!!!
11 */
12static inline int adfs_checkbblk(unsigned char *ptr)
13{
14 unsigned int result = 0;
15 unsigned char *p = ptr + 511;
16
17 do {
18 result = (result & 0xff) + (result >> 8);
19 result = result + *--p;
20 } while (p != ptr);
21
22 return (result & 0xff) != ptr[511];
23}
24#endif
25