/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ADFS_FS_H
#define _ADFS_FS_H

#include <uapi/linux/adfs_fs.h>

/*
 * Calculate the boot block checksum on an ADFS drive.  Note that this will
 * appear to be correct if the sector contains all zeros, so also check that
 * the disk size is non-zero!!!
 */
static inline int adfs_checkbblk(unsigned char *ptr)
{
        unsigned int result = 0;
        unsigned char *p = ptr + 511;

        do {
                result = (result & 0xff) + (result >> 8);
                result = result + *--p;
        } while (p != ptr);

        return (result & 0xff) != ptr[511];
}
#endif