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 static inline void set_page_count(struct page *page, int v)
  17 {
  18         atomic_set(&page->_count, v);
  19 }
  20
  21 /*
  22  * Turn a non-refcounted page (->_count == 0) into refcounted with
  23  * a count of one.
  24  */
  25 static inline void set_page_refcounted(struct page *page)
  26 {
  27         VM_BUG_ON(PageTail(page));
  28         VM_BUG_ON(atomic_read(&page->_count));
  29         set_page_count(page, 1);
  30 }
  31
  32 static inline void __put_page(struct page *page)
  33 {
  34         atomic_dec(&page->_count);
  35 }
  36
  37 extern void __init __free_pages_bootmem(struct page *page,
  38                                                 unsigned int order);
  39
  40 /*
  41  * function for dealing with page's order in buddy system.
  42  * zone->lock is already acquired when we use these.
  43  * So, we don't need atomic page->flags operations here.
  44  */
  45 static inline unsigned long page_order(struct page *page)
  46 {
  47         VM_BUG_ON(!PageBuddy(page));
  48         return page_private(page);
  49 }
  50
  51 /*
  52  * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node,
  53  * so all functions starting at paging_init should be marked __init
  54  * in those cases. SPARSEMEM, however, allows for memory hotplug,
  55  * and alloc_bootmem_node is not used.
  56  */
  57 #ifdef CONFIG_SPARSEMEM
  58 #define __paginginit __meminit
  59 #else
  60 #define __paginginit __init
  61 #endif
  62
  63 #endif