hugetlb.h 23.8 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950
/* SPDX-License-Identifier: GPL-2.0 */
#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>
#include <linux/pgtable.h>
#include <linux/gfp.h>

struct ctl_table;
struct user_struct;
struct mmu_gather;

#ifndef is_hugepd
typedef struct { unsigned long pd; } hugepd_t;
#define is_hugepd(hugepd) (0)
#define __hugepd(x) ((hugepd_t) { (x) })
#endif

#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;	/* Maximum huge pages or -1 if no maximum. */
	long used_hpages;	/* Used count against maximum, includes */
				/* both alloced and reserved pages. */
	struct hstate *hstate;
	long min_hpages;	/* Minimum huge pages or -1 if no minimum. */
	long rsv_hpages;	/* Pages reserved against global pool to */
				/* sasitfy minimum size. */
};

struct resv_map {
	struct kref refs;
	spinlock_t lock;
	struct list_head regions;
	long adds_in_progress;
	struct list_head region_cache;
	long region_cache_count;
#ifdef CONFIG_CGROUP_HUGETLB
	/*
	 * On private mappings, the counter to uncharge reservations is stored
	 * here. If these fields are 0, then either the mapping is shared, or
	 * cgroup accounting is disabled for this resv_map.
	 */
	struct page_counter *reservation_counter;
	unsigned long pages_per_hpage;
	struct cgroup_subsys_state *css;
#endif
};

/*
 * Region tracking -- allows tracking of reservations and instantiated pages
 *                    across the pages in a mapping.
 *
 * The region data structures are embedded into a resv_map and protected
 * by a resv_map's lock.  The set of regions within the resv_map represent
 * reservations for huge pages, or huge pages that have already been
 * instantiated within the map.  The from and to elements are huge page
 * indicies into the associated mapping.  from indicates the starting index
 * of the region.  to represents the first index past the end of  the region.
 *
 * For example, a file region structure with from == 0 and to == 4 represents
 * four huge pages in a mapping.  It is important to note that the to element
 * represents the first element past the end of the region. This is used in
 * arithmetic as 4(to) - 0(from) = 4 huge pages in the region.
 *
 * Interval notation of the form [from, to) will be used to indicate that
 * the endpoint from is inclusive and to is exclusive.
 */
struct file_region {
	struct list_head link;
	long from;
	long to;
#ifdef CONFIG_CGROUP_HUGETLB
	/*
	 * On shared mappings, each reserved region appears as a struct
	 * file_region in resv_map. These fields hold the info needed to
	 * uncharge each reservation.
	 */
	struct page_counter *reservation_counter;
	struct cgroup_subsys_state *css;
#endif
};

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(struct hstate *h, long max_hpages,
						long min_hpages);
void hugepage_put_subpool(struct hugepage_subpool *spool);

void reset_vma_resv_huge_pages(struct vm_area_struct *vma);
int hugetlb_sysctl_handler(struct ctl_table *, int, void *, size_t *, loff_t *);
int hugetlb_overcommit_handler(struct ctl_table *, int, void *, size_t *,
		loff_t *);
int hugetlb_treat_movable_handler(struct ctl_table *, int, void *, size_t *,
		loff_t *);
int hugetlb_mempolicy_sysctl_handler(struct ctl_table *, int, void *, size_t *,
		loff_t *);

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,
			 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(char *buf, int len, int nid);
void hugetlb_show_meminfo(void);
unsigned long hugetlb_total_pages(void);
vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
			unsigned long address, unsigned int flags);
int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, pte_t *dst_pte,
				struct vm_area_struct *dst_vma,
				unsigned long dst_addr,
				unsigned long src_addr,
				struct page **pagep);
int hugetlb_reserve_pages(struct inode *inode, long from, long to,
						struct vm_area_struct *vma,
						vm_flags_t vm_flags);
long hugetlb_unreserve_pages(struct inode *inode, long start, long end,
						long freed);
bool isolate_huge_page(struct page *page, struct list_head *list);
void putback_active_hugepage(struct page *page);
void move_hugetlb_state(struct page *oldpage, struct page *newpage, int reason);
void free_huge_page(struct page *page);
void hugetlb_fix_reserve_counts(struct inode *inode);
extern struct mutex *hugetlb_fault_mutex_table;
u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx);

pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud);

struct address_space *hugetlb_page_mapping_lock_write(struct page *hpage);

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, unsigned long sz);
int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma,
				unsigned long *addr, pte_t *ptep);
void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma,
				unsigned long *start, unsigned long *end);
struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
			      int write);
struct page *follow_huge_pd(struct vm_area_struct *vma,
			    unsigned long address, hugepd_t hpd,
			    int flags, int pdshift);
struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
				pmd_t *pmd, int flags);
struct page *follow_huge_pud(struct mm_struct *mm, unsigned long address,
				pud_t *pud, int flags);
struct page *follow_huge_pgd(struct mm_struct *mm, unsigned long address,
			     pgd_t *pgd, int flags);

int pmd_huge(pmd_t pmd);
int pud_huge(pud_t pud);
unsigned long hugetlb_change_protection(struct vm_area_struct *vma,
		unsigned long address, unsigned long end, pgprot_t newprot);

bool is_hugetlb_entry_migration(pte_t pte);

#else /* !CONFIG_HUGETLB_PAGE */

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

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

static inline struct address_space *hugetlb_page_mapping_lock_write(
							struct page *hpage)
{
	return NULL;
}

static inline int huge_pmd_unshare(struct mm_struct *mm,
					struct vm_area_struct *vma,
					unsigned long *addr, pte_t *ptep)
{
	return 0;
}

static inline void adjust_range_if_pmd_sharing_possible(
				struct vm_area_struct *vma,
				unsigned long *start, unsigned long *end)
{
}

static inline long follow_hugetlb_page(struct mm_struct *mm,
			struct vm_area_struct *vma, struct page **pages,
			struct vm_area_struct **vmas, unsigned long *position,
			unsigned long *nr_pages, long i, unsigned int flags,
			int *nonblocking)
{
	BUG();
	return 0;
}

static inline struct page *follow_huge_addr(struct mm_struct *mm,
					unsigned long address, int write)
{
	return ERR_PTR(-EINVAL);
}

static inline int copy_hugetlb_page_range(struct mm_struct *dst,
			struct mm_struct *src, struct vm_area_struct *vma)
{
	BUG();
	return 0;
}

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

static inline int hugetlb_report_node_meminfo(char *buf, int len, int nid)
{
	return 0;
}

static inline void hugetlb_show_meminfo(void)
{
}

static inline struct page *follow_huge_pd(struct vm_area_struct *vma,
				unsigned long address, hugepd_t hpd, int flags,
				int pdshift)
{
	return NULL;
}

static inline struct page *follow_huge_pmd(struct mm_struct *mm,
				unsigned long address, pmd_t *pmd, int flags)
{
	return NULL;
}

static inline struct page *follow_huge_pud(struct mm_struct *mm,
				unsigned long address, pud_t *pud, int flags)
{
	return NULL;
}

static inline struct page *follow_huge_pgd(struct mm_struct *mm,
				unsigned long address, pgd_t *pgd, int flags)
{
	return NULL;
}

static inline int prepare_hugepage_range(struct file *file,
				unsigned long addr, unsigned long len)
{
	return -EINVAL;
}

static inline int pmd_huge(pmd_t pmd)
{
	return 0;
}

static inline int pud_huge(pud_t pud)
{
	return 0;
}

static inline int is_hugepage_only_range(struct mm_struct *mm,
					unsigned long addr, unsigned long len)
{
	return 0;
}

static inline void hugetlb_free_pgd_range(struct mmu_gather *tlb,
				unsigned long addr, unsigned long end,
				unsigned long floor, unsigned long ceiling)
{
	BUG();
}

static inline int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
						pte_t *dst_pte,
						struct vm_area_struct *dst_vma,
						unsigned long dst_addr,
						unsigned long src_addr,
						struct page **pagep)
{
	BUG();
	return 0;
}

static inline pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr,
					unsigned long sz)
{
	return NULL;
}

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

static inline void putback_active_hugepage(struct page *page)
{
}

static inline void move_hugetlb_state(struct page *oldpage,
					struct page *newpage, int reason)
{
}

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();
}

static inline vm_fault_t hugetlb_fault(struct mm_struct *mm,
			struct vm_area_struct *vma, unsigned long address,
			unsigned int flags)
{
	BUG();
	return 0;
}

#endif /* !CONFIG_HUGETLB_PAGE */
/*
 * hugepages at page global directory. If arch support
 * hugepages at pgd level, they need to define this.
 */
#ifndef pgd_huge
#define pgd_huge(x)	0
#endif
#ifndef p4d_huge
#define p4d_huge(x)	0
#endif

#ifndef pgd_write
static inline int pgd_write(pgd_t pgd)
{
	BUG();
	return 0;
}
#endif

#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;
	kuid_t	uid;
	kgid_t	gid;
	umode_t mode;
};

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

struct hugetlbfs_inode_info {
	struct shared_policy policy;
	struct inode vfs_inode;
	unsigned int seals;
};

static inline struct hugetlbfs_inode_info *HUGETLBFS_I(struct inode *inode)
{
	return container_of(inode, struct hugetlbfs_inode_info, vfs_inode);
}

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 bool is_file_hugepages(struct file *file)
{
	if (file->f_op == &hugetlbfs_file_operations)
		return true;

	return is_file_shm_hugepages(file);
}

static inline struct hstate *hstate_inode(struct inode *i)
{
	return HUGETLBFS_SB(i->i_sb)->hstate;
}
#else /* !CONFIG_HUGETLBFS */

#define is_file_hugepages(file)			false
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);
}

static inline struct hstate *hstate_inode(struct inode *i)
{
	return NULL;
}
#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_dfl[7];
	struct cftype cgroup_files_legacy[9];
#endif
	char name[HSTATE_NAME_LEN];
};

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

struct page *alloc_huge_page(struct vm_area_struct *vma,
				unsigned long addr, int avoid_reserve);
struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid,
				nodemask_t *nmask, gfp_t gfp_mask);
struct page *alloc_huge_page_vma(struct hstate *h, struct vm_area_struct *vma,
				unsigned long address);
int huge_add_to_page_cache(struct page *page, struct address_space *mapping,
			pgoff_t idx);

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

void __init hugetlb_add_hstate(unsigned order);
bool __init arch_hugetlb_valid_size(unsigned long size);
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_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(1UL << 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 is_hugepage_only_range
static inline int is_hugepage_only_range(struct mm_struct *mm,
					unsigned long addr, unsigned long len)
{
	return 0;
}
#define is_hugepage_only_range is_hugepage_only_range
#endif

#ifndef arch_clear_hugepage_flags
static inline void arch_clear_hugepage_flags(struct page *page) { }
#define arch_clear_hugepage_flags arch_clear_hugepage_flags
#endif

#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(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 int dissolve_free_huge_page(struct page *page);
extern int dissolve_free_huge_pages(unsigned long start_pfn,
				    unsigned long end_pfn);

#ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION
#ifndef arch_hugetlb_migration_supported
static inline bool arch_hugetlb_migration_supported(struct hstate *h)
{
	if ((huge_page_shift(h) == PMD_SHIFT) ||
		(huge_page_shift(h) == PUD_SHIFT) ||
			(huge_page_shift(h) == PGDIR_SHIFT))
		return true;
	else
		return false;
}
#endif
#else
static inline bool arch_hugetlb_migration_supported(struct hstate *h)
{
	return false;
}
#endif

static inline bool hugepage_migration_supported(struct hstate *h)
{
	return arch_hugetlb_migration_supported(h);
}

/*
 * Movability check is different as compared to migration check.
 * It determines whether or not a huge page should be placed on
 * movable zone or not. Movability of any huge page should be
 * required only if huge page size is supported for migration.
 * There wont be any reason for the huge page to be movable if
 * it is not migratable to start with. Also the size of the huge
 * page should be large enough to be placed under a movable zone
 * and still feasible enough to be migratable. Just the presence
 * in movable zone does not make the migration feasible.
 *
 * So even though large huge page sizes like the gigantic ones
 * are migratable they should not be movable because its not
 * feasible to migrate them from movable zone.
 */
static inline bool hugepage_movable_supported(struct hstate *h)
{
	if (!hugepage_migration_supported(h))
		return false;

	if (hstate_is_gigantic(h))
		return false;
	return true;
}

/* Movability of hugepages depends on migration support. */
static inline gfp_t htlb_alloc_mask(struct hstate *h)
{
	if (hugepage_movable_supported(h))
		return GFP_HIGHUSER_MOVABLE;
	else
		return GFP_HIGHUSER;
}

static inline gfp_t htlb_modify_alloc_mask(struct hstate *h, gfp_t gfp_mask)
{
	gfp_t modified_mask = htlb_alloc_mask(h);

	/* Some callers might want to enforce node */
	modified_mask |= (gfp_mask & __GFP_THISNODE);

	modified_mask |= (gfp_mask & __GFP_NOWARN);

	return modified_mask;
}

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;
}

#ifndef hugepages_supported
/*
 * Some platform decide whether they support huge pages at boot
 * time. Some of them, such as powerpc, set HPAGE_SHIFT to 0
 * when there is no such support
 */
#define hugepages_supported() (HPAGE_SHIFT != 0)
#endif

void hugetlb_report_usage(struct seq_file *m, struct mm_struct *mm);

static inline void hugetlb_count_add(long l, struct mm_struct *mm)
{
	atomic_long_add(l, &mm->hugetlb_usage);
}

static inline void hugetlb_count_sub(long l, struct mm_struct *mm)
{
	atomic_long_sub(l, &mm->hugetlb_usage);
}

#ifndef set_huge_swap_pte_at
static inline void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
					pte_t *ptep, pte_t pte, unsigned long sz)
{
	set_huge_pte_at(mm, addr, ptep, pte);
}
#endif

#ifndef huge_ptep_modify_prot_start
#define huge_ptep_modify_prot_start huge_ptep_modify_prot_start
static inline pte_t huge_ptep_modify_prot_start(struct vm_area_struct *vma,
						unsigned long addr, pte_t *ptep)
{
	return huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
}
#endif

#ifndef huge_ptep_modify_prot_commit
#define huge_ptep_modify_prot_commit huge_ptep_modify_prot_commit
static inline void huge_ptep_modify_prot_commit(struct vm_area_struct *vma,
						unsigned long addr, pte_t *ptep,
						pte_t old_pte, pte_t pte)
{
	set_huge_pte_at(vma->vm_mm, addr, ptep, pte);
}
#endif

#else	/* CONFIG_HUGETLB_PAGE */
struct hstate {};

static inline struct page *alloc_huge_page(struct vm_area_struct *vma,
					   unsigned long addr,
					   int avoid_reserve)
{
	return NULL;
}

static inline struct page *
alloc_huge_page_nodemask(struct hstate *h, int preferred_nid,
			nodemask_t *nmask, gfp_t gfp_mask)
{
	return NULL;
}

static inline struct page *alloc_huge_page_vma(struct hstate *h,
					       struct vm_area_struct *vma,
					       unsigned long address)
{
	return NULL;
}

static inline int __alloc_bootmem_huge_page(struct hstate *h)
{
	return 0;
}

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

static inline struct hstate *hstate_sizelog(int page_size_log)
{
	return NULL;
}

static inline struct hstate *hstate_vma(struct vm_area_struct *vma)
{
	return NULL;
}

static inline struct hstate *page_hstate(struct page *page)
{
	return NULL;
}

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

static inline unsigned long huge_page_mask(struct hstate *h)
{
	return PAGE_MASK;
}

static inline unsigned long vma_kernel_pagesize(struct vm_area_struct *vma)
{
	return PAGE_SIZE;
}

static inline unsigned long vma_mmu_pagesize(struct vm_area_struct *vma)
{
	return PAGE_SIZE;
}

static inline unsigned int huge_page_order(struct hstate *h)
{
	return 0;
}

static inline unsigned int huge_page_shift(struct hstate *h)
{
	return PAGE_SHIFT;
}

static inline bool hstate_is_gigantic(struct hstate *h)
{
	return false;
}

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

static inline unsigned hstate_index_to_shift(unsigned index)
{
	return 0;
}

static inline int hstate_index(struct hstate *h)
{
	return 0;
}

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

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

static inline int dissolve_free_huge_pages(unsigned long start_pfn,
					   unsigned long end_pfn)
{
	return 0;
}

static inline bool hugepage_migration_supported(struct hstate *h)
{
	return false;
}

static inline bool hugepage_movable_supported(struct hstate *h)
{
	return false;
}

static inline gfp_t htlb_alloc_mask(struct hstate *h)
{
	return 0;
}

static inline gfp_t htlb_modify_alloc_mask(struct hstate *h, gfp_t gfp_mask)
{
	return 0;
}

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

static inline void hugetlb_report_usage(struct seq_file *f, struct mm_struct *m)
{
}

static inline void hugetlb_count_sub(long l, struct mm_struct *mm)
{
}

static inline void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
					pte_t *ptep, pte_t pte, unsigned long sz)
{
}
#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;
}

#if defined(CONFIG_HUGETLB_PAGE) && defined(CONFIG_CMA)
extern void __init hugetlb_cma_reserve(int order);
extern void __init hugetlb_cma_check(void);
#else
static inline __init void hugetlb_cma_reserve(int order)
{
}
static inline __init void hugetlb_cma_check(void)
{
}
#endif

#endif /* _LINUX_HUGETLB_H */