#ifndef _ADFS_FS_H
  #define _ADFS_FS_H
  
  #include <linux/types.h>

  #include <linux/magic.h>

  
  /*
   * Disc Record at disc address 0xc00
   */
  struct adfs_discrecord {
      __u8  log2secsize;
      __u8  secspertrack;
      __u8  heads;
      __u8  density;
      __u8  idlen;
      __u8  log2bpmb;
      __u8  skew;
      __u8  bootoption;
      __u8  lowsector;
      __u8  nzones;
      __le16 zone_spare;
      __le32 root;
      __le32 disc_size;
      __le16 disc_id;
      __u8  disc_name[10];
      __le32 disc_type;
      __le32 disc_size_high;
      __u8  log2sharesize:4;
      __u8  unused40:4;
      __u8  big_flag:1;
      __u8  unused41:1;
      __u8  nzones_high;
      __le32 format_version;
      __le32 root_size;
      __u8  unused52[60 - 52];
  };
  
  #define ADFS_DISCRECORD		(0xc00)
  #define ADFS_DR_OFFSET		(0x1c0)
  #define ADFS_DR_SIZE		 60
  #define ADFS_DR_SIZE_BITS	(ADFS_DR_SIZE << 3)

  
  #ifdef __KERNEL__

  /*
   * 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
  
  #endif