4 #include <linux/types.h>
7 * Disc Record at disc address 0xc00
9 struct adfs_discrecord {
34 __u8 unused52[60 - 52];
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
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!!!
49 static inline int adfs_checkbblk(unsigned char *ptr)
51 unsigned int result = 0;
52 unsigned char *p = ptr + 511;
55 result = (result & 0xff) + (result >> 8);
56 result = result + *--p;
59 return (result & 0xff) != ptr[511];