#ifndef _LINUX_HUGETLB_H
  #define _LINUX_HUGETLB_H

  #include <linux/mm_types.h>

  #include <linux/mmdebug.h>

  #include <linux/fs.h>

  #include <linux/hugetlb_inline.h>

  #include <linux/cgroup.h>

  #include <linux/list.h>
  #include <linux/kref.h>

  struct ctl_table;
  struct user_struct;

  struct mmu_gather;

  #ifdef CONFIG_HUGETLB_PAGE
  
  #include <linux/mempolicy.h>

  #include <linux/shm.h>

  #include <asm/tlbflush.h>

  struct hugepage_subpool {
  	spinlock_t lock;
  	long count;
  	long max_hpages, used_hpages;
  };

  struct resv_map {
  	struct kref refs;

  	spinlock_t lock;

  	struct list_head regions;
  };
  extern struct resv_map *resv_map_alloc(void);
  void resv_map_release(struct kref *ref);

  extern spinlock_t hugetlb_lock;
  extern int hugetlb_max_hstate __read_mostly;
  #define for_each_hstate(h) \
  	for ((h) = hstates; (h) < &hstates[hugetlb_max_hstate]; (h)++)

  struct hugepage_subpool *hugepage_new_subpool(long nr_blocks);
  void hugepage_put_subpool(struct hugepage_subpool *spool);

  int PageHuge(struct page *page);

  void reset_vma_resv_huge_pages(struct vm_area_struct *vma);

  int hugetlb_sysctl_handler(struct ctl_table *, int, void __user *, size_t *, loff_t *);
  int hugetlb_overcommit_handler(struct ctl_table *, int, void __user *, size_t *, loff_t *);
  int hugetlb_treat_movable_handler(struct ctl_table *, int, void __user *, size_t *, loff_t *);

  
  #ifdef CONFIG_NUMA
  int hugetlb_mempolicy_sysctl_handler(struct ctl_table *, int,
  					void __user *, size_t *, loff_t *);
  #endif

  int copy_hugetlb_page_range(struct mm_struct *, struct mm_struct *, struct vm_area_struct *);

  long follow_hugetlb_page(struct mm_struct *, struct vm_area_struct *,
  			 struct page **, struct vm_area_struct **,
  			 unsigned long *, unsigned long *, long, unsigned int);

  void unmap_hugepage_range(struct vm_area_struct *,

  			  unsigned long, unsigned long, struct page *);

  void __unmap_hugepage_range_final(struct mmu_gather *tlb,
  			  struct vm_area_struct *vma,
  			  unsigned long start, unsigned long end,
  			  struct page *ref_page);

  void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
  				unsigned long start, unsigned long end,
  				struct page *ref_page);

  void hugetlb_report_meminfo(struct seq_file *);

  int hugetlb_report_node_meminfo(int, char *);

  void hugetlb_show_meminfo(void);

  unsigned long hugetlb_total_pages(void);

  int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,

  			unsigned long address, unsigned int flags);

  int hugetlb_reserve_pages(struct inode *inode, long from, long to,

  						struct vm_area_struct *vma,

  						vm_flags_t vm_flags);

  void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed);

  int dequeue_hwpoisoned_huge_page(struct page *page);

  bool isolate_huge_page(struct page *page, struct list_head *list);
  void putback_active_hugepage(struct page *page);

  bool is_hugepage_active(struct page *page);

  void free_huge_page(struct page *page);

  #ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE
  pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud);
  #endif

  extern unsigned long hugepages_treat_as_movable;

  extern int sysctl_hugetlb_shm_group;

  extern struct list_head huge_boot_pages;

  /* arch callbacks */

  pte_t *huge_pte_alloc(struct mm_struct *mm,
  			unsigned long addr, unsigned long sz);

  pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr);

  int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep);

  struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
  			      int write);
  struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
  				pmd_t *pmd, int write);

  struct page *follow_huge_pud(struct mm_struct *mm, unsigned long address,
  				pud_t *pud, int write);

  int pmd_huge(pmd_t pmd);

  int pud_huge(pud_t pmd);

  unsigned long hugetlb_change_protection(struct vm_area_struct *vma,

  		unsigned long address, unsigned long end, pgprot_t newprot);

  #else /* !CONFIG_HUGETLB_PAGE */

  static inline int PageHuge(struct page *page)
  {
  	return 0;
  }

  static inline void reset_vma_resv_huge_pages(struct vm_area_struct *vma)
  {
  }

  static inline unsigned long hugetlb_total_pages(void)
  {
  	return 0;
  }

  #define follow_hugetlb_page(m,v,p,vs,a,b,i,w)	({ BUG(); 0; })

  #define follow_huge_addr(mm, addr, write)	ERR_PTR(-EINVAL)
  #define copy_hugetlb_page_range(src, dst, vma)	({ BUG(); 0; })

  static inline void hugetlb_report_meminfo(struct seq_file *m)
  {
  }

  #define hugetlb_report_node_meminfo(n, buf)	0

  static inline void hugetlb_show_meminfo(void)
  {
  }

  #define follow_huge_pmd(mm, addr, pmd, write)	NULL

  #define follow_huge_pud(mm, addr, pud, write)	NULL

  #define prepare_hugepage_range(file, addr, len)	(-EINVAL)

  #define pmd_huge(x)	0

  #define pud_huge(x)	0

  #define is_hugepage_only_range(mm, addr, len)	0

  #define hugetlb_free_pgd_range(tlb, addr, end, floor, ceiling) ({BUG(); 0; })

  #define hugetlb_fault(mm, vma, addr, flags)	({ BUG(); 0; })

  #define huge_pte_offset(mm, address)	0

  static inline int dequeue_hwpoisoned_huge_page(struct page *page)
  {
  	return 0;
  }

  static inline bool isolate_huge_page(struct page *page, struct list_head *list)
  {
  	return false;
  }

  #define putback_active_hugepage(p)	do {} while (0)

  #define is_hugepage_active(x)	false

  static inline unsigned long hugetlb_change_protection(struct vm_area_struct *vma,
  		unsigned long address, unsigned long end, pgprot_t newprot)
  {
  	return 0;
  }

  static inline void __unmap_hugepage_range_final(struct mmu_gather *tlb,
  			struct vm_area_struct *vma, unsigned long start,
  			unsigned long end, struct page *ref_page)
  {
  	BUG();
  }

  static inline void __unmap_hugepage_range(struct mmu_gather *tlb,
  			struct vm_area_struct *vma, unsigned long start,
  			unsigned long end, struct page *ref_page)
  {
  	BUG();
  }

  #endif /* !CONFIG_HUGETLB_PAGE */

  #define HUGETLB_ANON_FILE "anon_hugepage"

  enum {
  	/*
  	 * The file will be used as an shm file so shmfs accounting rules
  	 * apply
  	 */
  	HUGETLB_SHMFS_INODE     = 1,

  	/*
  	 * The file is being created on the internal vfs mount and shmfs
  	 * accounting rules do not apply
  	 */
  	HUGETLB_ANONHUGE_INODE  = 2,

  };

  #ifdef CONFIG_HUGETLBFS

  struct hugetlbfs_sb_info {

  	long	max_inodes;   /* inodes allowed */
  	long	free_inodes;  /* inodes free */
  	spinlock_t	stat_lock;

  	struct hstate *hstate;

  	struct hugepage_subpool *spool;

  };

  static inline struct hugetlbfs_sb_info *HUGETLBFS_SB(struct super_block *sb)
  {
  	return sb->s_fs_info;
  }

  extern const struct file_operations hugetlbfs_file_operations;

  extern const struct vm_operations_struct hugetlb_vm_ops;

  struct file *hugetlb_file_setup(const char *name, size_t size, vm_flags_t acct,

  				struct user_struct **user, int creat_flags,
  				int page_size_log);

  
  static inline int is_file_hugepages(struct file *file)
  {

  	if (file->f_op == &hugetlbfs_file_operations)
  		return 1;
  	if (is_file_shm_hugepages(file))
  		return 1;
  
  	return 0;

  }

  #else /* !CONFIG_HUGETLBFS */

  #define is_file_hugepages(file)			0

  static inline struct file *

  hugetlb_file_setup(const char *name, size_t size, vm_flags_t acctflag,
  		struct user_struct **user, int creat_flags,

  		int page_size_log)

  {
  	return ERR_PTR(-ENOSYS);
  }

  
  #endif /* !CONFIG_HUGETLBFS */

  #ifdef HAVE_ARCH_HUGETLB_UNMAPPED_AREA
  unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
  					unsigned long len, unsigned long pgoff,
  					unsigned long flags);
  #endif /* HAVE_ARCH_HUGETLB_UNMAPPED_AREA */

  #ifdef CONFIG_HUGETLB_PAGE

  #define HSTATE_NAME_LEN 32

  /* Defines one hugetlb page size */
  struct hstate {

  	int next_nid_to_alloc;
  	int next_nid_to_free;

  	unsigned int order;
  	unsigned long mask;
  	unsigned long max_huge_pages;
  	unsigned long nr_huge_pages;
  	unsigned long free_huge_pages;
  	unsigned long resv_huge_pages;
  	unsigned long surplus_huge_pages;
  	unsigned long nr_overcommit_huge_pages;

  	struct list_head hugepage_activelist;

  	struct list_head hugepage_freelists[MAX_NUMNODES];
  	unsigned int nr_huge_pages_node[MAX_NUMNODES];
  	unsigned int free_huge_pages_node[MAX_NUMNODES];
  	unsigned int surplus_huge_pages_node[MAX_NUMNODES];

  #ifdef CONFIG_CGROUP_HUGETLB
  	/* cgroup control files */
  	struct cftype cgroup_files[5];
  #endif

  	char name[HSTATE_NAME_LEN];

  };

  struct huge_bootmem_page {
  	struct list_head list;
  	struct hstate *hstate;

  #ifdef CONFIG_HIGHMEM
  	phys_addr_t phys;
  #endif

  };

  struct page *alloc_huge_page_node(struct hstate *h, int nid);

  struct page *alloc_huge_page_noerr(struct vm_area_struct *vma,
  				unsigned long addr, int avoid_reserve);

  /* arch callback */
  int __init alloc_bootmem_huge_page(struct hstate *h);

  void __init hugetlb_add_hstate(unsigned order);
  struct hstate *size_to_hstate(unsigned long size);
  
  #ifndef HUGE_MAX_HSTATE
  #define HUGE_MAX_HSTATE 1
  #endif
  
  extern struct hstate hstates[HUGE_MAX_HSTATE];
  extern unsigned int default_hstate_idx;
  
  #define default_hstate (hstates[default_hstate_idx])

  static inline struct hstate *hstate_inode(struct inode *i)

  {

  	struct hugetlbfs_sb_info *hsb;
  	hsb = HUGETLBFS_SB(i->i_sb);
  	return hsb->hstate;

  }
  
  static inline struct hstate *hstate_file(struct file *f)
  {

  	return hstate_inode(file_inode(f));

  }

  static inline struct hstate *hstate_sizelog(int page_size_log)
  {
  	if (!page_size_log)
  		return &default_hstate;
  	return size_to_hstate(1 << page_size_log);
  }

  static inline struct hstate *hstate_vma(struct vm_area_struct *vma)

  {

  	return hstate_file(vma->vm_file);

  }
  
  static inline unsigned long huge_page_size(struct hstate *h)
  {
  	return (unsigned long)PAGE_SIZE << h->order;
  }

  extern unsigned long vma_kernel_pagesize(struct vm_area_struct *vma);

  extern unsigned long vma_mmu_pagesize(struct vm_area_struct *vma);

  static inline unsigned long huge_page_mask(struct hstate *h)
  {
  	return h->mask;
  }
  
  static inline unsigned int huge_page_order(struct hstate *h)
  {
  	return h->order;
  }
  
  static inline unsigned huge_page_shift(struct hstate *h)
  {
  	return h->order + PAGE_SHIFT;
  }

  static inline bool hstate_is_gigantic(struct hstate *h)
  {
  	return huge_page_order(h) >= MAX_ORDER;
  }

  static inline unsigned int pages_per_huge_page(struct hstate *h)
  {
  	return 1 << h->order;
  }
  
  static inline unsigned int blocks_per_huge_page(struct hstate *h)
  {
  	return huge_page_size(h) / 512;
  }
  
  #include <asm/hugetlb.h>

  #ifndef arch_make_huge_pte
  static inline pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
  				       struct page *page, int writable)
  {
  	return entry;
  }
  #endif

  static inline struct hstate *page_hstate(struct page *page)
  {

  	VM_BUG_ON_PAGE(!PageHuge(page), page);

  	return size_to_hstate(PAGE_SIZE << compound_order(page));
  }

  static inline unsigned hstate_index_to_shift(unsigned index)
  {
  	return hstates[index].order + PAGE_SHIFT;
  }

  static inline int hstate_index(struct hstate *h)
  {
  	return h - hstates;
  }

  pgoff_t __basepage_index(struct page *page);
  
  /* Return page->index in PAGE_SIZE units */
  static inline pgoff_t basepage_index(struct page *page)
  {
  	if (!PageCompound(page))
  		return page->index;
  
  	return __basepage_index(page);
  }

  extern void dissolve_free_huge_pages(unsigned long start_pfn,
  				     unsigned long end_pfn);

  static inline int hugepage_migration_supported(struct hstate *h)

  {

  #ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION
  	return huge_page_shift(h) == PMD_SHIFT;
  #else
  	return 0;
  #endif

  }

  static inline spinlock_t *huge_pte_lockptr(struct hstate *h,
  					   struct mm_struct *mm, pte_t *pte)
  {
  	if (huge_page_size(h) == PMD_SIZE)
  		return pmd_lockptr(mm, (pmd_t *) pte);
  	VM_BUG_ON(huge_page_size(h) == PAGE_SIZE);
  	return &mm->page_table_lock;
  }

  static inline bool hugepages_supported(void)
  {
  	/*
  	 * Some platform decide whether they support huge pages at boot
  	 * time. On these, such as powerpc, HPAGE_SHIFT is set to 0 when
  	 * there is no such support
  	 */
  	return HPAGE_SHIFT != 0;
  }

  #else	/* CONFIG_HUGETLB_PAGE */

  struct hstate {};

  #define alloc_huge_page_node(h, nid) NULL

  #define alloc_huge_page_noerr(v, a, r) NULL

  #define alloc_bootmem_huge_page(h) NULL

  #define hstate_file(f) NULL

  #define hstate_sizelog(s) NULL

  #define hstate_vma(v) NULL
  #define hstate_inode(i) NULL

  #define page_hstate(page) NULL

  #define huge_page_size(h) PAGE_SIZE
  #define huge_page_mask(h) PAGE_MASK

  #define vma_kernel_pagesize(v) PAGE_SIZE

  #define vma_mmu_pagesize(v) PAGE_SIZE

  #define huge_page_order(h) 0
  #define huge_page_shift(h) PAGE_SHIFT

  static inline unsigned int pages_per_huge_page(struct hstate *h)
  {
  	return 1;
  }

  #define hstate_index_to_shift(index) 0

  #define hstate_index(h) 0

  
  static inline pgoff_t basepage_index(struct page *page)
  {
  	return page->index;
  }

  #define dissolve_free_huge_pages(s, e)	do {} while (0)

  #define hugepage_migration_supported(h)	0

  
  static inline spinlock_t *huge_pte_lockptr(struct hstate *h,
  					   struct mm_struct *mm, pte_t *pte)
  {
  	return &mm->page_table_lock;
  }

  #endif	/* CONFIG_HUGETLB_PAGE */

  static inline spinlock_t *huge_pte_lock(struct hstate *h,
  					struct mm_struct *mm, pte_t *pte)
  {
  	spinlock_t *ptl;
  
  	ptl = huge_pte_lockptr(h, mm, pte);
  	spin_lock(ptl);
  	return ptl;
  }

  #endif /* _LINUX_HUGETLB_H */