#ifndef _LINUX_VMALLOC_H
  #define _LINUX_VMALLOC_H
  
  #include <linux/spinlock.h>
  #include <asm/page.h>		/* pgprot_t */

  struct vm_area_struct;

  /* bits in vm_struct->flags */
  #define VM_IOREMAP	0x00000001	/* ioremap() and friends */
  #define VM_ALLOC	0x00000002	/* vmalloc() */
  #define VM_MAP		0x00000004	/* vmap()ed pages */

  #define VM_USERMAP	0x00000008	/* suitable for remap_vmalloc_range */

  #define VM_VPAGES	0x00000010	/* buffer for pages was vmalloc'ed */

  /* bits [20..32] reserved for arch specific ioremap internals */

  /*
   * Maximum alignment for ioremap() regions.
   * Can be overriden by arch-specific value.
   */
  #ifndef IOREMAP_MAX_ORDER
  #define IOREMAP_MAX_ORDER	(7 + PAGE_SHIFT)	/* 128 pages */
  #endif

  struct vm_struct {

  	/* keep next,addr,size together to speedup lookups */
  	struct vm_struct	*next;

  	void			*addr;
  	unsigned long		size;
  	unsigned long		flags;
  	struct page		**pages;
  	unsigned int		nr_pages;
  	unsigned long		phys_addr;

  };
  
  /*
   *	Highlevel APIs for driver use
   */
  extern void *vmalloc(unsigned long size);

  extern void *vmalloc_user(unsigned long size);

  extern void *vmalloc_node(unsigned long size, int node);

  extern void *vmalloc_exec(unsigned long size);
  extern void *vmalloc_32(unsigned long size);

  extern void *vmalloc_32_user(unsigned long size);

  extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot);

  extern void *__vmalloc_area(struct vm_struct *area, gfp_t gfp_mask,
  				pgprot_t prot);

  extern void vfree(void *addr);
  
  extern void *vmap(struct page **pages, unsigned int count,
  			unsigned long flags, pgprot_t prot);
  extern void vunmap(void *addr);

  
  extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
  							unsigned long pgoff);

  void vmalloc_sync_all(void);

   
  /*
   *	Lowlevel-APIs (not for driver use!)
   */

  
  static inline size_t get_vm_area_size(const struct vm_struct *area)
  {
  	/* return actual size without guard page */
  	return area->size - PAGE_SIZE;
  }

  extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
  extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
  					unsigned long start, unsigned long end);

  extern struct vm_struct *get_vm_area_node(unsigned long size,

  					  unsigned long flags, int node,
  					  gfp_t gfp_mask);

  extern struct vm_struct *remove_vm_area(void *addr);

  extern int map_vm_area(struct vm_struct *area, pgprot_t prot,
  			struct page ***pages);

  extern void unmap_kernel_range(unsigned long addr, unsigned long size);

  /* Allocate/destroy a 'vmalloc' VM area. */
  extern struct vm_struct *alloc_vm_area(size_t size);
  extern void free_vm_area(struct vm_struct *area);

  /*
   *	Internals.  Dont't use..
   */
  extern rwlock_t vmlist_lock;
  extern struct vm_struct *vmlist;
  
  #endif /* _LINUX_VMALLOC_H */