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);
  40
  41extern int migrate_prep(void);
  42extern int migrate_prep_local(void);
  43extern void migrate_page_copy(struct page *newpage, struct page *page);
  44extern int migrate_huge_page_move_mapping(struct address_space *mapping,
  45                                  struct page *newpage, struct page *page);
  46extern int migrate_page_move_mapping(struct address_space *mapping,
  47                struct page *newpage, struct page *page,
  48                struct buffer_head *head, enum migrate_mode mode,
  49                int extra_count);
  50#else
  51
  52static inline void putback_movable_pages(struct list_head *l) {}
  53static inline int migrate_pages(struct list_head *l, new_page_t new,
  54                free_page_t free, unsigned long private, enum migrate_mode mode,
  55                int reason)
  56        { return -ENOSYS; }
  57
  58static inline int migrate_prep(void) { return -ENOSYS; }
  59static inline int migrate_prep_local(void) { return -ENOSYS; }
  60
  61static inline void migrate_page_copy(struct page *newpage,
  62                                     struct page *page) {}
  63
  64static inline int migrate_huge_page_move_mapping(struct address_space *mapping,
  65                                  struct page *newpage, struct page *page)
  66{
  67        return -ENOSYS;
  68}
  69
  70#endif /* CONFIG_MIGRATION */
  71
  72#ifdef CONFIG_NUMA_BALANCING
  73extern bool pmd_trans_migrating(pmd_t pmd);
  74extern int migrate_misplaced_page(struct page *page,
  75                                  struct vm_area_struct *vma, int node);
  76#else
  77static inline bool pmd_trans_migrating(pmd_t pmd)
  78{
  79        return false;
  80}
  81static inline int migrate_misplaced_page(struct page *page,
  82                                         struct vm_area_struct *vma, int node)
  83{
  84        return -EAGAIN; /* can't migrate now */
  85}
  86#endif /* CONFIG_NUMA_BALANCING */
  87
  88#if defined(CONFIG_NUMA_BALANCING) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
  89extern int migrate_misplaced_transhuge_page(struct mm_struct *mm,
  90                        struct vm_area_struct *vma,
  91                        pmd_t *pmd, pmd_t entry,
  92                        unsigned long address,
  93                        struct page *page, int node);
  94#else
  95static inline int migrate_misplaced_transhuge_page(struct mm_struct *mm,
  96                        struct vm_area_struct *vma,
  97                        pmd_t *pmd, pmd_t entry,
  98                        unsigned long address,
  99                        struct page *page, int node)
 100{
 101        return -EAGAIN;
 102}
 103#endif /* CONFIG_NUMA_BALANCING && CONFIG_TRANSPARENT_HUGEPAGE*/
 104
 105#endif /* _LINUX_MIGRATE_H */
 106