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 | */ |
12 | static 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 | |