/* internal.h: mm/ internal definitions

*

* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.

* Written by David Howells ([email protected])

*

* This program is free software; you can redistribute it and/or

* modify it under the terms of the GNU General Public License

* as published by the Free Software Foundation; either version

* 2 of the License, or (at your option) any later version.

*/

#ifndef __MM_INTERNAL_H

#define __MM_INTERNAL_H

#include <linux/mm.h>

void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,

unsigned long floor, unsigned long ceiling);

static inline void set_page_count(struct page *page, int v)

{

atomic_set(&page->_count, v);

}

/*

* Turn a non-refcounted page (->_count == 0) into refcounted with

* a count of one.

*/

static inline void set_page_refcounted(struct page *page)

{

VM_BUG_ON(PageTail(page));

VM_BUG_ON(atomic_read(&page->_count));

set_page_count(page, 1);

}

static inline void __put_page(struct page *page)

{

atomic_dec(&page->_count);

}

static inline void __get_page_tail_foll(struct page *page,

bool get_page_head)

{

/*

* If we're getting a tail page, the elevated page->_count is

* required only in the head page and we will elevate the head

* page->_count and tail page->_mapcount.

*

* We elevate page_tail->_mapcount for tail pages to force

* page_tail->_count to be zero at all times to avoid getting

* false positives from get_page_unless_zero() with

* speculative page access (like in

* page_cache_get_speculative()) on tail pages.

*/

VM_BUG_ON(atomic_read(&page->first_page->_count) <= 0);

VM_BUG_ON(atomic_read(&page->_count) != 0);

VM_BUG_ON(page_mapcount(page) < 0);

if (get_page_head)

atomic_inc(&page->first_page->_count);

atomic_inc(&page->_mapcount);

}

/*

* This is meant to be called as the FOLL_GET operation of

* follow_page() and it must be called while holding the proper PT

* lock while the pte (or pmd_trans_huge) is still mapping the page.

*/

static inline void get_page_foll(struct page *page)

{

if (unlikely(PageTail(page)))

/*

* This is safe only because

* __split_huge_page_refcount() can't run under

* get_page_foll() because we hold the proper PT lock.

*/

__get_page_tail_foll(page, true);

else {

/*

* Getting a normal page or the head of a compound page

* requires to already have an elevated page->_count.

*/

VM_BUG_ON(atomic_read(&page->_count) <= 0);

atomic_inc(&page->_count);

}

}

extern unsigned long highest_memmap_pfn;

/*

* in mm/vmscan.c:

*/

extern int isolate_lru_page(struct page *page);

extern void putback_lru_page(struct page *page);

/*

* in mm/page_alloc.c

*/

extern void __free_pages_bootmem(struct page *page, unsigned int order);

extern void prep_compound_page(struct page *page, unsigned long order);

#ifdef CONFIG_MEMORY_FAILURE

extern bool is_free_buddy_page(struct page *page);

#endif

#if defined CONFIG_COMPACTION || defined CONFIG_CMA

/*

* in mm/compaction.c

*/

/*

* compact_control is used to track pages being migrated and the free pages

* they are being migrated to during memory compaction. The free_pfn starts

* at the end of a zone and migrate_pfn begins at the start. Movable pages

* are moved to the end of a zone during a compaction run and the run

* completes when free_pfn <= migrate_pfn

*/

struct compact_control {

struct list_head freepages; /* List of free pages to migrate to */

struct list_head migratepages; /* List of pages being migrated */

unsigned long nr_freepages; /* Number of isolated free pages */

unsigned long nr_migratepages; /* Number of pages to migrate */

unsigned long free_pfn; /* isolate_freepages search base */

unsigned long start_free_pfn; /* where we started the search */

unsigned long migrate_pfn; /* isolate_migratepages search base */

bool sync; /* Synchronous migration */

bool wrapped; /* Order > 0 compactions are

incremental, once free_pfn

and migrate_pfn meet, we restart

from the top of the zone;

remember we wrapped around. */

int order; /* order a direct compactor needs */

int migratetype; /* MOVABLE, RECLAIMABLE etc */

struct zone *zone;

bool *contended; /* True if a lock was contended */

};

unsigned long

isolate_freepages_range(unsigned long start_pfn, unsigned long end_pfn);

unsigned long

isolate_migratepages_range(struct zone *zone, struct compact_control *cc,

unsigned long low_pfn, unsigned long end_pfn);

#endif

/*

* function for dealing with page's order in buddy system.

* zone->lock is already acquired when we use these.

* So, we don't need atomic page->flags operations here.

*/

static inline unsigned long page_order(struct page *page)

{

/* PageBuddy() must be checked by the caller */

return page_private(page);

}

/* mm/util.c */

void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,

struct vm_area_struct *prev, struct rb_node *rb_parent);

#ifdef CONFIG_MMU

extern long mlock_vma_pages_range(struct vm_area_struct *vma,

unsigned long start, unsigned long end);

extern void munlock_vma_pages_range(struct vm_area_struct *vma,

unsigned long start, unsigned long end);

static inline void munlock_vma_pages_all(struct vm_area_struct *vma)

{

munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);

}

/*

* Called only in fault path via page_evictable() for a new page

* to determine if it's being mapped into a LOCKED vma.

* If so, mark page as mlocked.

*/

static inline int mlocked_vma_newpage(struct vm_area_struct *vma,

struct page *page)

{

VM_BUG_ON(PageLRU(page));

if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED))

return 0;

if (!TestSetPageMlocked(page)) {

inc_zone_page_state(page, NR_MLOCK);

count_vm_event(UNEVICTABLE_PGMLOCKED);

}

return 1;

}

/*

* must be called with vma's mmap_sem held for read or write, and page locked.

*/

extern void mlock_vma_page(struct page *page);

extern void munlock_vma_page(struct page *page);

/*

* Clear the page's PageMlocked(). This can be useful in a situation where

* we want to unconditionally remove a page from the pagecache -- e.g.,

* on truncation or freeing.

*

* It is legal to call this function for any page, mlocked or not.

* If called for a page that is still mapped by mlocked vmas, all we do

* is revert to lazy LRU behaviour -- semantics are not broken.

*/

extern void __clear_page_mlock(struct page *page);

static inline void clear_page_mlock(struct page *page)

{

if (unlikely(TestClearPageMlocked(page)))

__clear_page_mlock(page);

}

/*

* mlock_migrate_page - called only from migrate_page_copy() to

* migrate the Mlocked page flag; update statistics.

*/

static inline void mlock_migrate_page(struct page *newpage, struct page *page)

{

if (TestClearPageMlocked(page)) {

unsigned long flags;

local_irq_save(flags);

__dec_zone_page_state(page, NR_MLOCK);

SetPageMlocked(newpage);

__inc_zone_page_state(newpage, NR_MLOCK);

local_irq_restore(flags);

}

}

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

extern unsigned long vma_address(struct page *page,

struct vm_area_struct *vma);

#endif

#else /* !CONFIG_MMU */

static inline int mlocked_vma_newpage(struct vm_area_struct *v, struct page *p)

{

return 0;

}

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

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

static inline void mlock_migrate_page(struct page *new, struct page *old) { }

#endif /* !CONFIG_MMU */

/*

* Return the mem_map entry representing the 'offset' subpage within

* the maximally aligned gigantic page 'base'. Handle any discontiguity

* in the mem_map at MAX_ORDER_NR_PAGES boundaries.

*/

static inline struct page *mem_map_offset(struct page *base, int offset)

{

if (unlikely(offset >= MAX_ORDER_NR_PAGES))

return pfn_to_page(page_to_pfn(base) + offset);

return base + offset;

}

/*

* Iterator over all subpages within the maximally aligned gigantic

* page 'base'. Handle any discontiguity in the mem_map.

*/

static inline struct page *mem_map_next(struct page *iter,

struct page *base, int offset)

{

if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {

unsigned long pfn = page_to_pfn(base) + offset;

if (!pfn_valid(pfn))

return NULL;

return pfn_to_page(pfn);

}

return iter + 1;

}

/*

* FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node,

* so all functions starting at paging_init should be marked __init

* in those cases. SPARSEMEM, however, allows for memory hotplug,

* and alloc_bootmem_node is not used.

*/

#ifdef CONFIG_SPARSEMEM

#define __paginginit __meminit

#else

#define __paginginit __init

#endif

/* Memory initialisation debug and verification */

enum mminit_level {

MMINIT_WARNING,

MMINIT_VERIFY,

MMINIT_TRACE

};

#ifdef CONFIG_DEBUG_MEMORY_INIT

extern int mminit_loglevel;

#define mminit_dprintk(level, prefix, fmt, arg...) \

do { \

if (level < mminit_loglevel) { \

printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \

printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \

} \

} while (0)

extern void mminit_verify_pageflags_layout(void);

extern void mminit_verify_page_links(struct page *page,

enum zone_type zone, unsigned long nid, unsigned long pfn);

extern void mminit_verify_zonelist(void);

#else

static inline void mminit_dprintk(enum mminit_level level,

const char *prefix, const char *fmt, ...)

{

}

static inline void mminit_verify_pageflags_layout(void)

{

}

static inline void mminit_verify_page_links(struct page *page,

enum zone_type zone, unsigned long nid, unsigned long pfn)

{

}

static inline void mminit_verify_zonelist(void)

{

}

#endif /* CONFIG_DEBUG_MEMORY_INIT */

/* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */

#if defined(CONFIG_SPARSEMEM)

extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,

unsigned long *end_pfn);

#else

static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,

unsigned long *end_pfn)

{

}

#endif /* CONFIG_SPARSEMEM */

#define ZONE_RECLAIM_NOSCAN -2

#define ZONE_RECLAIM_FULL -1

#define ZONE_RECLAIM_SOME 0

#define ZONE_RECLAIM_SUCCESS 1

#endif

extern int hwpoison_filter(struct page *p);

extern u32 hwpoison_filter_dev_major;

extern u32 hwpoison_filter_dev_minor;

extern u64 hwpoison_filter_flags_mask;

extern u64 hwpoison_filter_flags_value;

extern u64 hwpoison_filter_memcg;

extern u32 hwpoison_filter_enable;

extern unsigned long vm_mmap_pgoff(struct file *, unsigned long,

unsigned long, unsigned long,

unsigned long, unsigned long);

extern void set_pageblock_order(void);