#ifndef _LINUX_KDEV_T_H
  #define _LINUX_KDEV_T_H

  
  #include <uapi/linux/kdev_t.h>

  #define MINORBITS	20
  #define MINORMASK	((1U << MINORBITS) - 1)
  
  #define MAJOR(dev)	((unsigned int) ((dev) >> MINORBITS))
  #define MINOR(dev)	((unsigned int) ((dev) & MINORMASK))
  #define MKDEV(ma,mi)	(((ma) << MINORBITS) | (mi))
  
  #define print_dev_t(buffer, dev)					\
  	sprintf((buffer), "%u:%u
  ", MAJOR(dev), MINOR(dev))
  
  #define format_dev_t(buffer, dev)					\
  	({								\
  		sprintf(buffer, "%u:%u", MAJOR(dev), MINOR(dev));	\
  		buffer;							\
  	})
  
  /* acceptable for old filesystems */
  static inline int old_valid_dev(dev_t dev)
  {
  	return MAJOR(dev) < 256 && MINOR(dev) < 256;
  }
  
  static inline u16 old_encode_dev(dev_t dev)
  {
  	return (MAJOR(dev) << 8) | MINOR(dev);
  }
  
  static inline dev_t old_decode_dev(u16 val)
  {
  	return MKDEV((val >> 8) & 255, val & 255);
  }
  
  static inline int new_valid_dev(dev_t dev)
  {
  	return 1;
  }
  
  static inline u32 new_encode_dev(dev_t dev)
  {
  	unsigned major = MAJOR(dev);
  	unsigned minor = MINOR(dev);
  	return (minor & 0xff) | (major << 8) | ((minor & ~0xff) << 12);
  }
  
  static inline dev_t new_decode_dev(u32 dev)
  {
  	unsigned major = (dev & 0xfff00) >> 8;
  	unsigned minor = (dev & 0xff) | ((dev >> 12) & 0xfff00);
  	return MKDEV(major, minor);
  }
  
  static inline int huge_valid_dev(dev_t dev)
  {
  	return 1;
  }
  
  static inline u64 huge_encode_dev(dev_t dev)
  {
  	return new_encode_dev(dev);
  }
  
  static inline dev_t huge_decode_dev(u64 dev)
  {
  	return new_decode_dev(dev);
  }
  
  static inline int sysv_valid_dev(dev_t dev)
  {
  	return MAJOR(dev) < (1<<14) && MINOR(dev) < (1<<18);
  }
  
  static inline u32 sysv_encode_dev(dev_t dev)
  {
  	return MINOR(dev) | (MAJOR(dev) << 18);
  }
  
  static inline unsigned sysv_major(u32 dev)
  {
  	return (dev >> 18) & 0x3fff;
  }
  
  static inline unsigned sysv_minor(u32 dev)
  {
  	return dev & 0x3ffff;
  }

  #endif