include/linux/hugetlb.h - kernel/msm-4.19 - Gitiles

 #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 const unsigned long hugetlb_zero, hugetlb_infinity;
 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 */
	#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 const unsigned long hugetlb_zero, hugetlb_infinity;
	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 */