[linux-2.6-block.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_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_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);
extern int migrate_page_move_mapping(struct address_space *mapping,
		struct page *newpage, struct page *page,
		struct buffer_head *head, enum migrate_mode mode,
		int extra_count);
#else

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_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

#endif /* CONFIG_MIGRATION */

#ifdef CONFIG_NUMA_BALANCING
extern bool pmd_trans_migrating(pmd_t pmd);
extern void wait_migrate_huge_page(struct anon_vma *anon_vma, pmd_t *pmd);
extern int migrate_misplaced_page(struct page *page,
				  struct vm_area_struct *vma, int node);
extern bool migrate_ratelimited(int node);
#else
static inline bool pmd_trans_migrating(pmd_t pmd)
{
	return false;
}
static inline void wait_migrate_huge_page(struct anon_vma *anon_vma, pmd_t *pmd)
{
}
static inline int migrate_misplaced_page(struct page *page,
					 struct vm_area_struct *vma, 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
b20a3503 CL	1	#ifndef _LINUX_MIGRATE_H
	2	#define _LINUX_MIGRATE_H
	3
b20a3503	4	#include <linux/mm.h>
906e0be1	5	#include <linux/mempolicy.h>
6536e312	6	#include <linux/migrate_mode.h>
b20a3503	7
742755a1	8	typedef struct page new_page_t(struct page , unsigned long private, int **);
95a402c3	9
78bd5209 RA	10	/*
	11	* Return values from addresss_space_operations.migratepage():
	12	* - negative errno on page migration failure;
	13	* - zero on page migration success;
18468d93 RA	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.
78bd5209 RA	21	*/
78bd5209 RA	22	#define MIGRATEPAGE_SUCCESS 0
18468d93 RA	23	#define MIGRATEPAGE_BALLOON_SUCCESS 1 /* special ret code for balloon page
	24	* sucessful migration case.
	25	*/
7b2a2d4a MG	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,
7039e1db	32	MR_NUMA_MISPLACED,
7b2a2d4a MG	33	MR_CMA
7b2a2d4a MG	34	};
78bd5209	35
906e0be1	36	#ifdef CONFIG_MIGRATION
64cdd548	37
5733c7d1	38	extern void putback_movable_pages(struct list_head *l);
2d1db3b1	39	extern int migrate_page(struct address_space *,
a6bc32b8	40	struct page , struct page , enum migrate_mode);
62b61f61	41	extern int migrate_pages(struct list_head *l, new_page_t x,
9c620e2b	42	unsigned long private, enum migrate_mode mode, int reason);
95a402c3	43
b20a3503	44	extern int migrate_prep(void);
748446bb	45	extern int migrate_prep_local(void);
7b2259b3 CL	46	extern int migrate_vmas(struct mm_struct *mm,
	47	const nodemask_t from, const nodemask_t to,
	48	unsigned long flags);
290408d4 NH	49	extern void migrate_page_copy(struct page newpage, struct page page);
	50	extern int migrate_huge_page_move_mapping(struct address_space *mapping,
	51	struct page newpage, struct page page);
36bc08cc GZ	52	extern int migrate_page_move_mapping(struct address_space *mapping,
36bc08cc GZ	53	struct page newpage, struct page page,
8e321fef BL	54	struct buffer_head *head, enum migrate_mode mode,
8e321fef BL	55	int extra_count);
b20a3503	56	#else
64cdd548	57
5733c7d1	58	static inline void putback_movable_pages(struct list_head *l) {}
95a402c3	59	static inline int migrate_pages(struct list_head *l, new_page_t x,
9c620e2b HD	60	unsigned long private, enum migrate_mode mode, int reason)
9c620e2b HD	61	{ return -ENOSYS; }
9bf9e89c	62
b20a3503	63	static inline int migrate_prep(void) { return -ENOSYS; }
748446bb	64	static inline int migrate_prep_local(void) { return -ENOSYS; }
b20a3503	65
7b2259b3 CL	66	static inline int migrate_vmas(struct mm_struct *mm,
	67	const nodemask_t from, const nodemask_t to,
	68	unsigned long flags)
	69	{
	70	return -ENOSYS;
	71	}
	72
290408d4 NH	73	static inline void migrate_page_copy(struct page *newpage,
	74	struct page *page) {}
	75
6f39ce05	76	static inline int migrate_huge_page_move_mapping(struct address_space *mapping,
290408d4 NH	77	struct page newpage, struct page page)
	78	{
	79	return -ENOSYS;
	80	}
	81
b20a3503 CL	82	/* Possible settings for the migrate_page() method in address_operations */
b20a3503 CL	83	#define migrate_page NULL
b20a3503 CL	84
b20a3503 CL	85	#endif /* CONFIG_MIGRATION */
7039e1db PZ	86
7039e1db PZ	87	#ifdef CONFIG_NUMA_BALANCING
de466bd6 MG	88	extern bool pmd_trans_migrating(pmd_t pmd);
de466bd6 MG	89	extern void wait_migrate_huge_page(struct anon_vma anon_vma, pmd_t pmd);
1bc115d8 MG	90	extern int migrate_misplaced_page(struct page *page,
1bc115d8 MG	91	struct vm_area_struct *vma, int node);
e14808b4	92	extern bool migrate_ratelimited(int node);
7039e1db	93	#else
de466bd6 MG	94	static inline bool pmd_trans_migrating(pmd_t pmd)
	95	{
	96	return false;
	97	}
	98	static inline void wait_migrate_huge_page(struct anon_vma anon_vma, pmd_t pmd)
	99	{
	100	}
1bc115d8 MG	101	static inline int migrate_misplaced_page(struct page *page,
1bc115d8 MG	102	struct vm_area_struct *vma, int node)
7039e1db PZ	103	{
	104	return -EAGAIN; /* can't migrate now */
	105	}
e14808b4 MG	106	static inline bool migrate_ratelimited(int node)
	107	{
	108	return false;
	109	}
220018d3	110	#endif /* CONFIG_NUMA_BALANCING */
b32967ff	111
220018d3 MG	112	#if defined(CONFIG_NUMA_BALANCING) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
	113	extern int migrate_misplaced_transhuge_page(struct mm_struct *mm,
	114	struct vm_area_struct *vma,
	115	pmd_t *pmd, pmd_t entry,
	116	unsigned long address,
	117	struct page *page, int node);
	118	#else
b32967ff MG	119	static inline int migrate_misplaced_transhuge_page(struct mm_struct *mm,
	120	struct vm_area_struct *vma,
	121	pmd_t *pmd, pmd_t entry,
	122	unsigned long address,
	123	struct page *page, int node)
	124	{
	125	return -EAGAIN;
	126	}
220018d3	127	#endif /* CONFIG_NUMA_BALANCING && CONFIG_TRANSPARENT_HUGEPAGE*/
7039e1db	128
b20a3503	129	#endif /* _LINUX_MIGRATE_H */