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
  16 void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
  17                 unsigned long floor, unsigned long ceiling);
  18
  19 extern void prep_compound_page(struct page *page, unsigned long order);
  20 extern void prep_compound_gigantic_page(struct page *page, unsigned long order);
  21
  22 static inline void set_page_count(struct page *page, int v)
  23 {
  24         atomic_set(&page->_count, v);
  25 }
  26
  27 /*
  28  * Turn a non-refcounted page (->_count == 0) into refcounted with
  29  * a count of one.
  30  */
  31 static inline void set_page_refcounted(struct page *page)
  32 {
  33         VM_BUG_ON(PageTail(page));
  34         VM_BUG_ON(atomic_read(&page->_count));
  35         set_page_count(page, 1);
  36 }
  37
  38 static inline void __put_page(struct page *page)
  39 {
  40         atomic_dec(&page->_count);
  41 }
  42
  43 extern void __free_pages_bootmem(struct page *page, unsigned int order);
  44
  45 /*
  46  * function for dealing with page's order in buddy system.
  47  * zone->lock is already acquired when we use these.
  48  * So, we don't need atomic page->flags operations here.
  49  */
  50 static inline unsigned long page_order(struct page *page)
  51 {
  52         /* PageBuddy() must be checked by the caller */
  53         return page_private(page);
  54 }
  55
  56 /*
  57  * Return the mem_map entry representing the 'offset' subpage within
  58  * the maximally aligned gigantic page 'base'.  Handle any discontiguity
  59  * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
  60  */
  61 static inline struct page *mem_map_offset(struct page *base, int offset)
  62 {
  63         if (unlikely(offset >= MAX_ORDER_NR_PAGES))
  64                 return pfn_to_page(page_to_pfn(base) + offset);
  65         return base + offset;
  66 }
  67
  68 /*
  69  * Iterator over all subpages withing the maximally aligned gigantic
  70  * page 'base'.  Handle any discontiguity in the mem_map.
  71  */
  72 static inline struct page *mem_map_next(struct page *iter,
  73                                                 struct page *base, int offset)
  74 {
  75         if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) {
  76                 unsigned long pfn = page_to_pfn(base) + offset;
  77                 if (!pfn_valid(pfn))
  78                         return NULL;
  79                 return pfn_to_page(pfn);
  80         }
  81         return iter + 1;
  82 }
  83
  84 /*
  85  * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node,
  86  * so all functions starting at paging_init should be marked __init
  87  * in those cases. SPARSEMEM, however, allows for memory hotplug,
  88  * and alloc_bootmem_node is not used.
  89  */
  90 #ifdef CONFIG_SPARSEMEM
  91 #define __paginginit __meminit
  92 #else
  93 #define __paginginit __init
  94 #endif
  95
  96 /* Memory initialisation debug and verification */
  97 enum mminit_level {
  98         MMINIT_WARNING,
  99         MMINIT_VERIFY,
 100         MMINIT_TRACE
 101 };
 102
 103 #ifdef CONFIG_DEBUG_MEMORY_INIT
 104
 105 extern int mminit_loglevel;
 106
 107 #define mminit_dprintk(level, prefix, fmt, arg...) \
 108 do { \
 109         if (level < mminit_loglevel) { \
 110                 printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \
 111                 printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \
 112         } \
 113 } while (0)
 114
 115 extern void mminit_verify_pageflags_layout(void);
 116 extern void mminit_verify_page_links(struct page *page,
 117                 enum zone_type zone, unsigned long nid, unsigned long pfn);
 118 extern void mminit_verify_zonelist(void);
 119
 120 #else
 121
 122 static inline void mminit_dprintk(enum mminit_level level,
 123                                 const char *prefix, const char *fmt, ...)
 124 {
 125 }
 126
 127 static inline void mminit_verify_pageflags_layout(void)
 128 {
 129 }
 130
 131 static inline void mminit_verify_page_links(struct page *page,
 132                 enum zone_type zone, unsigned long nid, unsigned long pfn)
 133 {
 134 }
 135
 136 static inline void mminit_verify_zonelist(void)
 137 {
 138 }
 139 #endif /* CONFIG_DEBUG_MEMORY_INIT */
 140
 141 /* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
 142 #if defined(CONFIG_SPARSEMEM)
 143 extern void mminit_validate_memmodel_limits(unsigned long *start_pfn,
 144                                 unsigned long *end_pfn);
 145 #else
 146 static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
 147                                 unsigned long *end_pfn)
 148 {
 149 }
 150 #endif /* CONFIG_SPARSEMEM */
 151
 152 #endif