1 #ifndef _LINUX_MIGRATE_H 2 #define _LINUX_MIGRATE_H 3 4 #include <linux/mm.h> 5 #include <linux/mempolicy.h> 6 #include <linux/pagemap.h> 7 8 typedef struct page *new_page_t(struct page *, unsigned long private, int **); 9 10 #ifdef CONFIG_MIGRATION 11 /* Check if a vma is migratable */ 12 static inline int vma_migratable(struct vm_area_struct *vma) 13 { 14 if (vma->vm_flags & (VM_IO|VM_HUGETLB|VM_PFNMAP|VM_RESERVED)) 15 return 0; 16 /* 17 * Migration allocates pages in the highest zone. If we cannot 18 * do so then migration (at least from node to node) is not 19 * possible. 20 */ 21 if (vma->vm_file && 22 gfp_zone(mapping_gfp_mask(vma->vm_file->f_mapping)) 23 < policy_zone) 24 return 0; 25 return 1; 26 } 27 28 extern int isolate_lru_page(struct page *p, struct list_head *pagelist); 29 extern int putback_lru_pages(struct list_head *l); 30 extern int migrate_page(struct address_space *, 31 struct page *, struct page *); 32 extern int migrate_pages(struct list_head *l, new_page_t x, unsigned long); 33 34 extern int fail_migrate_page(struct address_space *, 35 struct page *, struct page *); 36 37 extern int migrate_prep(void); 38 extern int migrate_vmas(struct mm_struct *mm, 39 const nodemask_t *from, const nodemask_t *to, 40 unsigned long flags); 41 #else 42 static inline int vma_migratable(struct vm_area_struct *vma) 43 { return 0; } 44 45 static inline int isolate_lru_page(struct page *p, struct list_head *list) 46 { return -ENOSYS; } 47 static inline int putback_lru_pages(struct list_head *l) { return 0; } 48 static inline int migrate_pages(struct list_head *l, new_page_t x, 49 unsigned long private) { return -ENOSYS; } 50 51 static inline int migrate_pages_to(struct list_head *pagelist, 52 struct vm_area_struct *vma, int dest) { return 0; } 53 54 static inline int migrate_prep(void) { return -ENOSYS; } 55 56 static inline int migrate_vmas(struct mm_struct *mm, 57 const nodemask_t *from, const nodemask_t *to, 58 unsigned long flags) 59 { 60 return -ENOSYS; 61 } 62 63 /* Possible settings for the migrate_page() method in address_operations */ 64 #define migrate_page NULL 65 #define fail_migrate_page NULL 66 67 #endif /* CONFIG_MIGRATION */ 68 #endif /* _LINUX_MIGRATE_H */ 69