android_kernel_asus_sm8350/include/linux/hugetlb.h
Mike Kravetz 8c07792e79 hugetlb: check for undefined shift on 32 bit architectures
commit ec4288fe63966b26d53907212ecd05dfa81dd2cc upstream.

Users can specify the hugetlb page size in the mmap, shmget and
memfd_create system calls.  This is done by using 6 bits within the flags
argument to encode the base-2 logarithm of the desired page size.  The
routine hstate_sizelog() uses the log2 value to find the corresponding
hugetlb hstate structure.  Converting the log2 value (page_size_log) to
potential hugetlb page size is the simple statement:

	1UL << page_size_log

Because only 6 bits are used for page_size_log, the left shift can not be
greater than 63.  This is fine on 64 bit architectures where a long is 64
bits.  However, if a value greater than 31 is passed on a 32 bit
architecture (where long is 32 bits) the shift will result in undefined
behavior.  This was generally not an issue as the result of the undefined
shift had to exactly match hugetlb page size to proceed.

Recent improvements in runtime checking have resulted in this undefined
behavior throwing errors such as reported below.

Fix by comparing page_size_log to BITS_PER_LONG before doing shift.

Link: https://lkml.kernel.org/r/20230216013542.138708-1-mike.kravetz@oracle.com
Link: https://lore.kernel.org/lkml/CA+G9fYuei_Tr-vN9GS7SfFyU1y9hNysnf=PB7kT0=yv4MiPgVg@mail.gmail.com/
Fixes: 42d7395feb ("mm: support more pagesizes for MAP_HUGETLB/SHM_HUGETLB")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reviewed-by: Jesper Juhl <jesperjuhl76@gmail.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Sasha Levin <sashal@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-22 12:50:39 +01:00

764 lines
20 KiB
C

/* 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/page_ref.h>
#include <linux/list.h>
#include <linux/kref.h>
#include <asm/pgtable.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;
};
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 __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,
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);
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 hstate *h, struct address_space *mapping,
pgoff_t idx);
pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud);
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, 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_pte(struct vm_area_struct *vma, unsigned long address,
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 int huge_pmd_unshare(struct mm_struct *mm, 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)
{
}
#define follow_hugetlb_page(m,v,p,vs,a,b,i,w,n) ({ 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_pd(vma, addr, hpd, flags, pdshift) NULL
#define follow_huge_pmd_pte(vma, addr, flags) NULL
#define follow_huge_pud(mm, addr, pud, flags) NULL
#define follow_huge_pgd(mm, addr, pgd, flags) 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_mcopy_atomic_pte(dst_mm, dst_pte, dst_vma, dst_addr, \
src_addr, pagep) ({ BUG(); 0; })
#define huge_pte_offset(mm, address, sz) 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 move_hugetlb_state(old, new, reason) do {} while (0)
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[5];
#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_node(struct hstate *h, int nid);
struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid,
nodemask_t *nmask);
struct page *alloc_huge_page_vma(struct hstate *h, struct vm_area_struct *vma,
unsigned long address);
struct page *alloc_migrate_huge_page(struct hstate *h, gfp_t gfp_mask,
int nid, nodemask_t *nmask);
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_bad_size(void);
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_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;
if (page_size_log < BITS_PER_LONG)
return size_to_hstate(1UL << page_size_log);
return NULL;
}
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(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;
}
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;
}
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_init(struct mm_struct *mm)
{
atomic_long_set(&mm->hugetlb_usage, 0);
}
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
void set_page_huge_active(struct page *page);
#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_node(struct hstate *h, int nid)
{
return NULL;
}
static inline struct page *
alloc_huge_page_nodemask(struct hstate *h, int preferred_nid, nodemask_t *nmask)
{
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 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 spinlock_t *huge_pte_lockptr(struct hstate *h,
struct mm_struct *mm, pte_t *pte)
{
return &mm->page_table_lock;
}
static inline void hugetlb_count_init(struct mm_struct *mm)
{
}
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;
}
#ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE
static inline bool hugetlb_pmd_shared(pte_t *pte)
{
return page_count(virt_to_page(pte)) > 1;
}
#else
static inline bool hugetlb_pmd_shared(pte_t *pte)
{
return false;
}
#endif
#endif /* _LINUX_HUGETLB_H */