#ifndef _LINUX_MMAN_H
  #define _LINUX_MMAN_H

  #include <asm/mman.h>
  
  #define MREMAP_MAYMOVE	1
  #define MREMAP_FIXED	2
  
  #define OVERCOMMIT_GUESS		0
  #define OVERCOMMIT_ALWAYS		1
  #define OVERCOMMIT_NEVER		2

  
  #ifdef __KERNEL__

  #include <linux/mm.h>

  #include <linux/percpu_counter.h>

  #include <linux/atomic.h>

  extern int sysctl_overcommit_memory;
  extern int sysctl_overcommit_ratio;

  extern struct percpu_counter vm_committed_as;

  static inline void vm_acct_memory(long pages)
  {

  	percpu_counter_add(&vm_committed_as, pages);

  }

  
  static inline void vm_unacct_memory(long pages)
  {
  	vm_acct_memory(-pages);
  }
  
  /*

   * Allow architectures to handle additional protection bits
   */
  
  #ifndef arch_calc_vm_prot_bits
  #define arch_calc_vm_prot_bits(prot) 0
  #endif
  
  #ifndef arch_vm_get_page_prot
  #define arch_vm_get_page_prot(vm_flags) __pgprot(0)
  #endif
  
  #ifndef arch_validate_prot
  /*
   * This is called from mprotect().  PROT_GROWSDOWN and PROT_GROWSUP have
   * already been masked out.
   *
   * Returns true if the prot flags are valid
   */
  static inline int arch_validate_prot(unsigned long prot)
  {
  	return (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM)) == 0;
  }
  #define arch_validate_prot arch_validate_prot
  #endif
  
  /*

   * Optimisation macro.  It is equivalent to:
   *      (x & bit1) ? bit2 : 0
   * but this version is faster.
   * ("bit1" and "bit2" must be single bits)
   */
  #define _calc_vm_trans(x, bit1, bit2) \
    ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \
     : ((x) & (bit1)) / ((bit1) / (bit2)))
  
  /*
   * Combine the mmap "prot" argument into "vm_flags" used internally.
   */
  static inline unsigned long
  calc_vm_prot_bits(unsigned long prot)
  {
  	return _calc_vm_trans(prot, PROT_READ,  VM_READ ) |
  	       _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) |

  	       _calc_vm_trans(prot, PROT_EXEC,  VM_EXEC) |
  	       arch_calc_vm_prot_bits(prot);

  }
  
  /*
   * Combine the mmap "flags" argument into "vm_flags" used internally.
   */
  static inline unsigned long
  calc_vm_flag_bits(unsigned long flags)
  {
  	return _calc_vm_trans(flags, MAP_GROWSDOWN,  VM_GROWSDOWN ) |
  	       _calc_vm_trans(flags, MAP_DENYWRITE,  VM_DENYWRITE ) |
  	       _calc_vm_trans(flags, MAP_EXECUTABLE, VM_EXECUTABLE) |
  	       _calc_vm_trans(flags, MAP_LOCKED,     VM_LOCKED    );
  }

  #endif /* __KERNEL__ */

  #endif /* _LINUX_MMAN_H */