[mirror_ubuntu-zesty-kernel.git] / include / linux / migrate.h

#ifndef _LINUX_MIGRATE_H
#define _LINUX_MIGRATE_H

#include <linux/mm.h>
#include <linux/mempolicy.h>
#include <linux/migrate_mode.h>

typedef struct page *new_page_t(struct page *, unsigned long private, int **);

/*
 * Return values from addresss_space_operations.migratepage():
 * - negative errno on page migration failure;
 * - zero on page migration success;
 *
 * The balloon page migration introduces this special case where a 'distinct'
 * return code is used to flag a successful page migration to unmap_and_move().
 * This approach is necessary because page migration can race against balloon
 * deflation procedure, and for such case we could introduce a nasty page leak
 * if a successfully migrated balloon page gets released concurrently with
 * migration's unmap_and_move() wrap-up steps.
 */
#define MIGRATEPAGE_SUCCESS		0
#define MIGRATEPAGE_BALLOON_SUCCESS	1 /* special ret code for balloon page
					   * sucessful migration case.
					   */
enum migrate_reason {
	MR_COMPACTION,
	MR_MEMORY_FAILURE,
	MR_MEMORY_HOTPLUG,
	MR_SYSCALL,		/* also applies to cpusets */
	MR_MEMPOLICY_MBIND,
	MR_NUMA_MISPLACED,
	MR_CMA
};

#ifdef CONFIG_MIGRATION

extern void putback_lru_pages(struct list_head *l);
extern void putback_movable_pages(struct list_head *l);
extern int migrate_page(struct address_space *,
			struct page *, struct page *, enum migrate_mode);
extern int migrate_pages(struct list_head *l, new_page_t x,
		unsigned long private, enum migrate_mode mode, int reason);
extern int migrate_huge_page(struct page *, new_page_t x,
		unsigned long private, enum migrate_mode mode);

extern int fail_migrate_page(struct address_space *,
			struct page *, struct page *);

extern int migrate_prep(void);
extern int migrate_prep_local(void);
extern int migrate_vmas(struct mm_struct *mm,
		const nodemask_t *from, const nodemask_t *to,
		unsigned long flags);
extern void migrate_page_copy(struct page *newpage, struct page *page);
extern int migrate_huge_page_move_mapping(struct address_space *mapping,
				  struct page *newpage, struct page *page);
#else

static inline void putback_lru_pages(struct list_head *l) {}
static inline void putback_movable_pages(struct list_head *l) {}
static inline int migrate_pages(struct list_head *l, new_page_t x,
		unsigned long private, enum migrate_mode mode, int reason)
	{ return -ENOSYS; }
static inline int migrate_huge_page(struct page *page, new_page_t x,
		unsigned long private, enum migrate_mode mode)
	{ return -ENOSYS; }

static inline int migrate_prep(void) { return -ENOSYS; }
static inline int migrate_prep_local(void) { return -ENOSYS; }

static inline int migrate_vmas(struct mm_struct *mm,
		const nodemask_t *from, const nodemask_t *to,
		unsigned long flags)
{
	return -ENOSYS;
}

static inline void migrate_page_copy(struct page *newpage,
				     struct page *page) {}

static inline int migrate_huge_page_move_mapping(struct address_space *mapping,
				  struct page *newpage, struct page *page)
{
	return -ENOSYS;
}

/* Possible settings for the migrate_page() method in address_operations */
#define migrate_page NULL
#define fail_migrate_page NULL

#endif /* CONFIG_MIGRATION */

#ifdef CONFIG_NUMA_BALANCING
extern int migrate_misplaced_page(struct page *page, int node);
extern int migrate_misplaced_page(struct page *page, int node);
extern bool migrate_ratelimited(int node);
#else
static inline int migrate_misplaced_page(struct page *page, int node)
{
	return -EAGAIN; /* can't migrate now */
}
static inline bool migrate_ratelimited(int node)
{
	return false;
}
#endif /* CONFIG_NUMA_BALANCING */

#if defined(CONFIG_NUMA_BALANCING) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
extern int migrate_misplaced_transhuge_page(struct mm_struct *mm,
			struct vm_area_struct *vma,
			pmd_t *pmd, pmd_t entry,
			unsigned long address,
			struct page *page, int node);
#else
static inline int migrate_misplaced_transhuge_page(struct mm_struct *mm,
			struct vm_area_struct *vma,
			pmd_t *pmd, pmd_t entry,
			unsigned long address,
			struct page *page, int node)
{
	return -EAGAIN;
}
#endif /* CONFIG_NUMA_BALANCING && CONFIG_TRANSPARENT_HUGEPAGE*/

#endif /* _LINUX_MIGRATE_H */
Commit	Line	Data
	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
	8	typedef struct page new_page_t(struct page , unsigned long private, int **);
	9
	10	/*
	11	* Return values from addresss_space_operations.migratepage():
	12	* - negative errno on page migration failure;
	13	* - zero on page migration success;
	14	*
	15	* The balloon page migration introduces this special case where a 'distinct'
	16	* return code is used to flag a successful page migration to unmap_and_move().
	17	* This approach is necessary because page migration can race against balloon
	18	* deflation procedure, and for such case we could introduce a nasty page leak
	19	* if a successfully migrated balloon page gets released concurrently with
	20	* migration's unmap_and_move() wrap-up steps.
	21	*/
	22	#define MIGRATEPAGE_SUCCESS 0
	23	#define MIGRATEPAGE_BALLOON_SUCCESS 1 /* special ret code for balloon page
	24	* sucessful migration case.
	25	*/
	26	enum migrate_reason {
	27	MR_COMPACTION,
	28	MR_MEMORY_FAILURE,
	29	MR_MEMORY_HOTPLUG,
	30	MR_SYSCALL, /* also applies to cpusets */
	31	MR_MEMPOLICY_MBIND,
	32	MR_NUMA_MISPLACED,
	33	MR_CMA
	34	};
	35
	36	#ifdef CONFIG_MIGRATION
	37
	38	extern void putback_lru_pages(struct list_head *l);
	39	extern void putback_movable_pages(struct list_head *l);
	40	extern int migrate_page(struct address_space *,
	41	struct page , struct page , enum migrate_mode);
	42	extern int migrate_pages(struct list_head *l, new_page_t x,
	43	unsigned long private, enum migrate_mode mode, int reason);
	44	extern int migrate_huge_page(struct page *, new_page_t x,
	45	unsigned long private, enum migrate_mode mode);
	46
	47	extern int fail_migrate_page(struct address_space *,
	48	struct page , struct page );
	49
	50	extern int migrate_prep(void);
	51	extern int migrate_prep_local(void);
	52	extern int migrate_vmas(struct mm_struct *mm,
	53	const nodemask_t from, const nodemask_t to,
	54	unsigned long flags);
	55	extern void migrate_page_copy(struct page newpage, struct page page);
	56	extern int migrate_huge_page_move_mapping(struct address_space *mapping,
	57	struct page newpage, struct page page);
	58	#else
	59
	60	static inline void putback_lru_pages(struct list_head *l) {}
	61	static inline void putback_movable_pages(struct list_head *l) {}
	62	static inline int migrate_pages(struct list_head *l, new_page_t x,
	63	unsigned long private, enum migrate_mode mode, int reason)
	64	{ return -ENOSYS; }
	65	static inline int migrate_huge_page(struct page *page, new_page_t x,
	66	unsigned long private, enum migrate_mode mode)
	67	{ return -ENOSYS; }
	68
	69	static inline int migrate_prep(void) { return -ENOSYS; }
	70	static inline int migrate_prep_local(void) { return -ENOSYS; }
	71
	72	static inline int migrate_vmas(struct mm_struct *mm,
	73	const nodemask_t from, const nodemask_t to,
	74	unsigned long flags)
	75	{
	76	return -ENOSYS;
	77	}
	78
	79	static inline void migrate_page_copy(struct page *newpage,
	80	struct page *page) {}
	81
	82	static inline int migrate_huge_page_move_mapping(struct address_space *mapping,
	83	struct page newpage, struct page page)
	84	{
	85	return -ENOSYS;
	86	}
	87
	88	/* Possible settings for the migrate_page() method in address_operations */
	89	#define migrate_page NULL
	90	#define fail_migrate_page NULL
	91
	92	#endif /* CONFIG_MIGRATION */
	93
	94	#ifdef CONFIG_NUMA_BALANCING
	95	extern int migrate_misplaced_page(struct page *page, int node);
	96	extern int migrate_misplaced_page(struct page *page, int node);
	97	extern bool migrate_ratelimited(int node);
	98	#else
	99	static inline int migrate_misplaced_page(struct page *page, int node)
	100	{
	101	return -EAGAIN; /* can't migrate now */
	102	}
	103	static inline bool migrate_ratelimited(int node)
	104	{
	105	return false;
	106	}
	107	#endif /* CONFIG_NUMA_BALANCING */
	108
	109	#if defined(CONFIG_NUMA_BALANCING) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
	110	extern int migrate_misplaced_transhuge_page(struct mm_struct *mm,
	111	struct vm_area_struct *vma,
	112	pmd_t *pmd, pmd_t entry,
	113	unsigned long address,
	114	struct page *page, int node);
	115	#else
	116	static inline int migrate_misplaced_transhuge_page(struct mm_struct *mm,
	117	struct vm_area_struct *vma,
	118	pmd_t *pmd, pmd_t entry,
	119	unsigned long address,
	120	struct page *page, int node)
	121	{
	122	return -EAGAIN;
	123	}
	124	#endif /* CONFIG_NUMA_BALANCING && CONFIG_TRANSPARENT_HUGEPAGE*/
	125
	126	#endif /* _LINUX_MIGRATE_H */