LXR linux/include/linux/migrate.h

   1#ifndef _LINUX_MIGRATE_H
   2#define _LINUX_MIGRATE_H
   3
   4#include <linux/mm.h>
   5#include <linux/mempolicy.h>
   6#include <linux/migrate_mode.h>
   7
   8typedef struct page *new_page_t(struct page *page, unsigned long private,
   9                                int **reason);
  10typedef void free_page_t(struct page *page, unsigned long private);
  11
  12/*
  13 * Return values from addresss_space_operations.migratepage():
  14 * - negative errno on page migration failure;
  15 * - zero on page migration success;
  16 */
  17#define MIGRATEPAGE_SUCCESS             0
  18
  19enum migrate_reason {
  20        MR_COMPACTION,
  21        MR_MEMORY_FAILURE,
  22        MR_MEMORY_HOTPLUG,
  23        MR_SYSCALL,             /* also applies to cpusets */
  24        MR_MEMPOLICY_MBIND,
  25        MR_NUMA_MISPLACED,
  26        MR_CMA,
  27        MR_TYPES
  28};
  29
  30/* In mm/debug.c; also keep sync with include/trace/events/migrate.h */
  31extern char *migrate_reason_names[MR_TYPES];
  32
  33#ifdef CONFIG_MIGRATION
  34
  35extern void putback_movable_pages(struct list_head *l);
  36extern int migrate_page(struct address_space *,
  37                        struct page *, struct page *, enum migrate_mode);
  38extern int migrate_pages(struct list_head *l, new_page_t new, free_page_t free,
  39                unsigned long private, enum migrate_mode mode, int reason);
  40extern int isolate_movable_page(struct page *page, isolate_mode_t mode);
  41extern void putback_movable_page(struct page *page);
  42
  43extern int migrate_prep(void);
  44extern int migrate_prep_local(void);
  45extern void migrate_page_copy(struct page *newpage, struct page *page);
  46extern int migrate_huge_page_move_mapping(struct address_space *mapping,
  47                                  struct page *newpage, struct page *page);
  48extern int migrate_page_move_mapping(struct address_space *mapping,
  49                struct page *newpage, struct page *page,
  50                struct buffer_head *head, enum migrate_mode mode,
  51                int extra_count);
  52#else
  53
  54static inline void putback_movable_pages(struct list_head *l) {}
  55static inline int migrate_pages(struct list_head *l, new_page_t new,
  56                free_page_t free, unsigned long private, enum migrate_mode mode,
  57                int reason)
  58        { return -ENOSYS; }
  59static inline int isolate_movable_page(struct page *page, isolate_mode_t mode)
  60        { return -EBUSY; }
  61
  62static inline int migrate_prep(void) { return -ENOSYS; }
  63static inline int migrate_prep_local(void) { return -ENOSYS; }
  64
  65static inline void migrate_page_copy(struct page *newpage,
  66                                     struct page *page) {}
  67
  68static inline int migrate_huge_page_move_mapping(struct address_space *mapping,
  69                                  struct page *newpage, struct page *page)
  70{
  71        return -ENOSYS;
  72}
  73
  74#endif /* CONFIG_MIGRATION */
  75
  76#ifdef CONFIG_COMPACTION
  77extern int PageMovable(struct page *page);
  78extern void __SetPageMovable(struct page *page, struct address_space *mapping);
  79extern void __ClearPageMovable(struct page *page);
  80#else
  81static inline int PageMovable(struct page *page) { return 0; };
  82static inline void __SetPageMovable(struct page *page,
  83                                struct address_space *mapping)
  84{
  85}
  86static inline void __ClearPageMovable(struct page *page)
  87{
  88}
  89#endif
  90
  91#ifdef CONFIG_NUMA_BALANCING
  92extern bool pmd_trans_migrating(pmd_t pmd);
  93extern int migrate_misplaced_page(struct page *page,
  94                                  struct vm_area_struct *vma, int node);
  95#else
  96static inline bool pmd_trans_migrating(pmd_t pmd)
  97{
  98        return false;
  99}
 100static inline int migrate_misplaced_page(struct page *page,
 101                                         struct vm_area_struct *vma, int node)
 102{
 103        return -EAGAIN; /* can't migrate now */
 104}
 105#endif /* CONFIG_NUMA_BALANCING */
 106
 107#if defined(CONFIG_NUMA_BALANCING) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
 108extern int migrate_misplaced_transhuge_page(struct mm_struct *mm,
 109                        struct vm_area_struct *vma,
 110                        pmd_t *pmd, pmd_t entry,
 111                        unsigned long address,
 112                        struct page *page, int node);
 113#else
 114static inline int migrate_misplaced_transhuge_page(struct mm_struct *mm,
 115                        struct vm_area_struct *vma,
 116                        pmd_t *pmd, pmd_t entry,
 117                        unsigned long address,
 118                        struct page *page, int node)
 119{
 120        return -EAGAIN;
 121}
 122#endif /* CONFIG_NUMA_BALANCING && CONFIG_TRANSPARENT_HUGEPAGE*/
 123
 124#endif /* _LINUX_MIGRATE_H */
 125