LXR linux/mm/internal.h

   1/* internal.h: mm/ internal definitions
   2 *
   3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
   4 * Written by David Howells (dhowells@redhat.com)
   5 *
   6 * This program is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public License
   8 * as published by the Free Software Foundation; either version
   9 * 2 of the License, or (at your option) any later version.
  10 */
  11#ifndef __MM_INTERNAL_H
  12#define __MM_INTERNAL_H
  13
  14#include <linux/mm.h>
  15
  16void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
  17                unsigned long floor, unsigned long ceiling);
  18
  19static inline void set_page_count(struct page *page, int v)
  20{
  21        atomic_set(&page->_count, v);
  22}
  23
  24/*
  25 * Turn a non-refcounted page (->_count == 0) into refcounted with
  26 * a count of one.
  27 */
  28static inline void set_page_refcounted(struct page *page)
  29{
  30        VM_BUG_ON(PageTail(page));
  31        VM_BUG_ON(atomic_read(&page->_count));
  32        set_page_count(page, 1);
  33}
  34
  35static inline void __put_page(struct page *page)
  36{
  37        atomic_dec(&page->_count);
  38}
  39
  40extern unsigned long highest_memmap_pfn;
  41
  42/*
  43 * in mm/vmscan.c:
  44 */
  45extern int isolate_lru_page(struct page *page);
  46extern void putback_lru_page(struct page *page);
  47
  48/*
  49 * in mm/page_alloc.c
  50 */
  51extern void __free_pages_bootmem(struct page *page, unsigned int order);
  52extern void prep_compound_page(struct page *page, unsigned long order);
  53#ifdef CONFIG_MEMORY_FAILURE
  54extern bool is_free_buddy_page(struct page *page);
  55#endif
  56
  57
  58/*
  59 * function for dealing with page's order in buddy system.
  60 * zone->lock is already acquired when we use these.
  61 * So, we don't need atomic page->flags operations here.
  62 */
  63static inline unsigned long page_order(struct page *page)
  64{
  65        VM_BUG_ON(!PageBuddy(page));
  66        return page_private(page);
  67}
  68
  69#ifdef CONFIG_MMU
  70extern long mlock_vma_pages_range(struct vm_area_struct *vma,
  71                        unsigned long start, unsigned long end);
  72extern void munlock_vma_pages_range(struct vm_area_struct *vma,
  73                        unsigned long start, unsigned long end);
  74static inline void munlock_vma_pages_all(struct vm_area_struct *vma)
  75{
  76        munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end);
  77}
  78
  79/*
  80 * Called only in fault path via page_evictable() for a new page
  81 * to determine if it's being mapped into a LOCKED vma.
  82 * If so, mark page as mlocked.
  83 */
  84static inline int is_mlocked_vma(struct vm_area_struct *vma, struct page *page)
  85{
  86        VM_BUG_ON(PageLRU(page));
  87
  88        if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED))
  89                return 0;
  90
  91        if (!TestSetPageMlocked(page)) {
  92                inc_zone_page_state(page, NR_MLOCK);
  93                count_vm_event(UNEVICTABLE_PGMLOCKED);
  94        }
  95        return 1;
  96}
  97
  98/*
  99 * must be called with vma's mmap_sem held for read or write, and page locked.
 100 */
 101extern void mlock_vma_page(struct page *page);
 102extern void munlock_vma_page(struct page *page);
 103
 104/*
 105 * Clear the page's PageMlocked().  This can be useful in a situation where
 106 * we want to unconditionally remove a page from the pagecache -- e.g.,
 107 * on truncation or freeing.
 108 *
 109 * It is legal to call this function for any page, mlocked or not.
 110 * If called for a page that is still mapped by mlocked vmas, all we do
 111 * is revert to lazy LRU behaviour -- semantics are not broken.
 112 */
 113extern void __clear_page_mlock(struct page *page);
 114static inline void clear_page_mlock(struct page *page)
 115{
 116        if (unlikely(TestClearPageMlocked(page)))
 117                __clear_page_mlock(page);
 118}
 119
 120/*
 121 * mlock_migrate_page - called only from migrate_page_copy() to
 122 * migrate the Mlocked page flag; update statistics.
 123 */
 124static inline void mlock_migrate_page(struct page *newpage, struct page *page)
 125{
 126        if (TestClearPageMlocked(page)) {
 127                unsigned long flags;
 128
 129                local_irq_save(flags);
 130                __dec_zone_page_state(page, NR_MLOCK);
 131                SetPageMlocked(newpage);
 132                __inc_zone_page_state(newpage, NR_MLOCK);
 133                local_irq_restore(flags);
 134        }
 135}
 136
 137#else /* !CONFIG_MMU */
 138static inline int is_mlocked_vma(struct vm_area_struct *v, struct page *p)
 139{
 140        return 0;
 141}
 142static inline void clear_page_mlock(struct page *page) { }
 143static inline void mlock_vma_page(struct page *page) { }
 144static inline void mlock_migrate_page(struct page *new, struct page *old) { }
 145
 146#endif /* !CONFIG_MMU */
 147
 148/*
 149 * Return the mem_map entry representing the 'offset' subpage within
 150 * the maximally aligned gigantic page 'base'.  Handle any discontiguity
 151 * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
 152 */
 153static inline struct page *mem_map_offset(struct page *base, int offset)
 154{
 155        if (unlikely(offset >= MAX_ORDER_NR_PAGES))
 156                return pfn_to_page(page_to_pfn(base) + offset);
 157        return base + offset;
 158}
 159
 160/*
 161 * Iterator over all subpages withing the maximally aligned gigantic
 162 * page 'base'.  Handle any discontiguity in the mem_map.
 163 */
 164static inline struct page *mem_map_next(struct page *iter,
 165                                                struct page *base, int offset)
 166{
 167        if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
 168                unsigned long pfn = page_to_pfn(base) + offset;
 169                if (!pfn_valid(pfn))
 170                        return NULL;
 171                return pfn_to_page(pfn);
 172        }
 173        return iter + 1;
 174}
 175
 176/*
 177 * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node,
 178 * so all functions starting at paging_init should be marked __init
 179 * in those cases. SPARSEMEM, however, allows for memory hotplug,
 180 * and alloc_bootmem_node is not used.
 181 */
 182#ifdef CONFIG_SPARSEMEM
 183#define __paginginit __meminit
 184#else
 185#define __paginginit __init
 186#endif
 187
 188/* Memory initialisation debug and verification */
 189enum mminit_level {
 190        MMINIT_WARNING,
 191        MMINIT_VERIFY,
 192        MMINIT_TRACE
 193};
 194
 195#ifdef CONFIG_DEBUG_MEMORY_INIT
 196
 197extern int mminit_loglevel;
 198
 199#define mminit_dprintk(level, prefix, fmt, arg...) \
 200do { \
 201        if (level < mminit_loglevel) { \
 202                printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \
 203                printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \
 204        } \
 205} while (0)
 206
 207extern void mminit_verify_pageflags_layout(void);
 208extern void mminit_verify_page_links(struct page *page,
 209                enum zone_type zone, unsigned long nid, unsigned long pfn);
 210extern void mminit_verify_zonelist(void);
 211
 212#else
 213
 214static inline void mminit_dprintk(enum mminit_level level,
 215                                const char *prefix, const char *fmt, ...)
 216{
 217}
 218
 219static inline void mminit_verify_pageflags_layout(void)
 220{
 221}
 222
 223static inline void mminit_verify_page_links(struct page *page,
 224                enum zone_type zone, unsigned long nid, unsigned long pfn)
 225{
 226}
 227
 228static inline void mminit_verify_zonelist(void)
 229{
 230}
 231#endif /* CONFIG_DEBUG_MEMORY_INIT */
 232
 233/* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
 234#if defined(CONFIG_SPARSEMEM)
 235extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,
 236                                unsigned long *end_pfn);
 237#else
 238static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
 239                                unsigned long *end_pfn)
 240{
 241}
 242#endif /* CONFIG_SPARSEMEM */
 243
 244int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 245                     unsigned long start, int len, unsigned int foll_flags,
 246                     struct page **pages, struct vm_area_struct **vmas);
 247
 248#define ZONE_RECLAIM_NOSCAN     -2
 249#define ZONE_RECLAIM_FULL       -1
 250#define ZONE_RECLAIM_SOME       0
 251#define ZONE_RECLAIM_SUCCESS    1
 252#endif
 253
 254extern int hwpoison_filter(struct page *p);
 255
 256extern u32 hwpoison_filter_dev_major;
 257extern u32 hwpoison_filter_dev_minor;
 258extern u64 hwpoison_filter_flags_mask;
 259extern u64 hwpoison_filter_flags_value;
 260extern u64 hwpoison_filter_memcg;
 261extern u32 hwpoison_filter_enable;
 262