[mirror_ubuntu-jammy-kernel.git] / include / linux / swapops.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_SWAPOPS_H
#define _LINUX_SWAPOPS_H

#include <linux/radix-tree.h>
#include <linux/bug.h>
#include <linux/mm_types.h>

#ifdef CONFIG_MMU

/*
 * swapcache pages are stored in the swapper_space radix tree.  We want to
 * get good packing density in that tree, so the index should be dense in
 * the low-order bits.
 *
 * We arrange the `type' and `offset' fields so that `type' is at the seven
 * high-order bits of the swp_entry_t and `offset' is right-aligned in the
 * remaining bits.  Although `type' itself needs only five bits, we allow for
 * shmem/tmpfs to shift it all up a further two bits: see swp_to_radix_entry().
 *
 * swp_entry_t's are *never* stored anywhere in their arch-dependent format.
 */
#define SWP_TYPE_SHIFT	(BITS_PER_XA_VALUE - MAX_SWAPFILES_SHIFT)
#define SWP_OFFSET_MASK	((1UL << SWP_TYPE_SHIFT) - 1)

/*
 * Store a type+offset into a swp_entry_t in an arch-independent format
 */
static inline swp_entry_t swp_entry(unsigned long type, pgoff_t offset)
{
	swp_entry_t ret;

	ret.val = (type << SWP_TYPE_SHIFT) | (offset & SWP_OFFSET_MASK);
	return ret;
}

/*
 * Extract the `type' field from a swp_entry_t.  The swp_entry_t is in
 * arch-independent format
 */
static inline unsigned swp_type(swp_entry_t entry)
{
	return (entry.val >> SWP_TYPE_SHIFT);
}

/*
 * Extract the `offset' field from a swp_entry_t.  The swp_entry_t is in
 * arch-independent format
 */
static inline pgoff_t swp_offset(swp_entry_t entry)
{
	return entry.val & SWP_OFFSET_MASK;
}

/* check whether a pte points to a swap entry */
static inline int is_swap_pte(pte_t pte)
{
	return !pte_none(pte) && !pte_present(pte);
}

/*
 * Convert the arch-dependent pte representation of a swp_entry_t into an
 * arch-independent swp_entry_t.
 */
static inline swp_entry_t pte_to_swp_entry(pte_t pte)
{
	swp_entry_t arch_entry;

	if (pte_swp_soft_dirty(pte))
		pte = pte_swp_clear_soft_dirty(pte);
	arch_entry = __pte_to_swp_entry(pte);
	return swp_entry(__swp_type(arch_entry), __swp_offset(arch_entry));
}

/*
 * Convert the arch-independent representation of a swp_entry_t into the
 * arch-dependent pte representation.
 */
static inline pte_t swp_entry_to_pte(swp_entry_t entry)
{
	swp_entry_t arch_entry;

	arch_entry = __swp_entry(swp_type(entry), swp_offset(entry));
	return __swp_entry_to_pte(arch_entry);
}

static inline swp_entry_t radix_to_swp_entry(void *arg)
{
	swp_entry_t entry;

	entry.val = xa_to_value(arg);
	return entry;
}

static inline void *swp_to_radix_entry(swp_entry_t entry)
{
	return xa_mk_value(entry.val);
}

#if IS_ENABLED(CONFIG_DEVICE_PRIVATE)
static inline swp_entry_t make_device_private_entry(struct page *page, bool write)
{
	return swp_entry(write ? SWP_DEVICE_WRITE : SWP_DEVICE_READ,
			 page_to_pfn(page));
}

static inline bool is_device_private_entry(swp_entry_t entry)
{
	int type = swp_type(entry);
	return type == SWP_DEVICE_READ || type == SWP_DEVICE_WRITE;
}

static inline void make_device_private_entry_read(swp_entry_t *entry)
{
	*entry = swp_entry(SWP_DEVICE_READ, swp_offset(*entry));
}

static inline bool is_write_device_private_entry(swp_entry_t entry)
{
	return unlikely(swp_type(entry) == SWP_DEVICE_WRITE);
}

static inline unsigned long device_private_entry_to_pfn(swp_entry_t entry)
{
	return swp_offset(entry);
}

static inline struct page *device_private_entry_to_page(swp_entry_t entry)
{
	return pfn_to_page(swp_offset(entry));
}
#else /* CONFIG_DEVICE_PRIVATE */
static inline swp_entry_t make_device_private_entry(struct page *page, bool write)
{
	return swp_entry(0, 0);
}

static inline void make_device_private_entry_read(swp_entry_t *entry)
{
}

static inline bool is_device_private_entry(swp_entry_t entry)
{
	return false;
}

static inline bool is_write_device_private_entry(swp_entry_t entry)
{
	return false;
}

static inline unsigned long device_private_entry_to_pfn(swp_entry_t entry)
{
	return 0;
}

static inline struct page *device_private_entry_to_page(swp_entry_t entry)
{
	return NULL;
}
#endif /* CONFIG_DEVICE_PRIVATE */

#ifdef CONFIG_MIGRATION
static inline swp_entry_t make_migration_entry(struct page *page, int write)
{
	BUG_ON(!PageLocked(compound_head(page)));

	return swp_entry(write ? SWP_MIGRATION_WRITE : SWP_MIGRATION_READ,
			page_to_pfn(page));
}

static inline int is_migration_entry(swp_entry_t entry)
{
	return unlikely(swp_type(entry) == SWP_MIGRATION_READ ||
			swp_type(entry) == SWP_MIGRATION_WRITE);
}

static inline int is_write_migration_entry(swp_entry_t entry)
{
	return unlikely(swp_type(entry) == SWP_MIGRATION_WRITE);
}

static inline unsigned long migration_entry_to_pfn(swp_entry_t entry)
{
	return swp_offset(entry);
}

static inline struct page *migration_entry_to_page(swp_entry_t entry)
{
	struct page *p = pfn_to_page(swp_offset(entry));
	/*
	 * Any use of migration entries may only occur while the
	 * corresponding page is locked
	 */
	BUG_ON(!PageLocked(compound_head(p)));
	return p;
}

static inline void make_migration_entry_read(swp_entry_t *entry)
{
	*entry = swp_entry(SWP_MIGRATION_READ, swp_offset(*entry));
}

extern void __migration_entry_wait(struct mm_struct *mm, pte_t *ptep,
					spinlock_t *ptl);
extern void migration_entry_wait(struct mm_struct *mm, pmd_t *pmd,
					unsigned long address);
extern void migration_entry_wait_huge(struct vm_area_struct *vma,
		struct mm_struct *mm, pte_t *pte);
#else

#define make_migration_entry(page, write) swp_entry(0, 0)
static inline int is_migration_entry(swp_entry_t swp)
{
	return 0;
}

static inline unsigned long migration_entry_to_pfn(swp_entry_t entry)
{
	return 0;
}

static inline struct page *migration_entry_to_page(swp_entry_t entry)
{
	return NULL;
}

static inline void make_migration_entry_read(swp_entry_t *entryp) { }
static inline void __migration_entry_wait(struct mm_struct *mm, pte_t *ptep,
					spinlock_t *ptl) { }
static inline void migration_entry_wait(struct mm_struct *mm, pmd_t *pmd,
					 unsigned long address) { }
static inline void migration_entry_wait_huge(struct vm_area_struct *vma,
		struct mm_struct *mm, pte_t *pte) { }
static inline int is_write_migration_entry(swp_entry_t entry)
{
	return 0;
}

#endif

struct page_vma_mapped_walk;

#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
extern void set_pmd_migration_entry(struct page_vma_mapped_walk *pvmw,
		struct page *page);

extern void remove_migration_pmd(struct page_vma_mapped_walk *pvmw,
		struct page *new);

extern void pmd_migration_entry_wait(struct mm_struct *mm, pmd_t *pmd);

static inline swp_entry_t pmd_to_swp_entry(pmd_t pmd)
{
	swp_entry_t arch_entry;

	if (pmd_swp_soft_dirty(pmd))
		pmd = pmd_swp_clear_soft_dirty(pmd);
	arch_entry = __pmd_to_swp_entry(pmd);
	return swp_entry(__swp_type(arch_entry), __swp_offset(arch_entry));
}

static inline pmd_t swp_entry_to_pmd(swp_entry_t entry)
{
	swp_entry_t arch_entry;

	arch_entry = __swp_entry(swp_type(entry), swp_offset(entry));
	return __swp_entry_to_pmd(arch_entry);
}

static inline int is_pmd_migration_entry(pmd_t pmd)
{
	return !pmd_present(pmd) && is_migration_entry(pmd_to_swp_entry(pmd));
}
#else
static inline void set_pmd_migration_entry(struct page_vma_mapped_walk *pvmw,
		struct page *page)
{
	BUILD_BUG();
}

static inline void remove_migration_pmd(struct page_vma_mapped_walk *pvmw,
		struct page *new)
{
	BUILD_BUG();
}

static inline void pmd_migration_entry_wait(struct mm_struct *m, pmd_t *p) { }

static inline swp_entry_t pmd_to_swp_entry(pmd_t pmd)
{
	return swp_entry(0, 0);
}

static inline pmd_t swp_entry_to_pmd(swp_entry_t entry)
{
	return __pmd(0);
}

static inline int is_pmd_migration_entry(pmd_t pmd)
{
	return 0;
}
#endif

#ifdef CONFIG_MEMORY_FAILURE

extern atomic_long_t num_poisoned_pages __read_mostly;

/*
 * Support for hardware poisoned pages
 */
static inline swp_entry_t make_hwpoison_entry(struct page *page)
{
	BUG_ON(!PageLocked(page));
	return swp_entry(SWP_HWPOISON, page_to_pfn(page));
}

static inline int is_hwpoison_entry(swp_entry_t entry)
{
	return swp_type(entry) == SWP_HWPOISON;
}

static inline void num_poisoned_pages_inc(void)
{
	atomic_long_inc(&num_poisoned_pages);
}

static inline void num_poisoned_pages_dec(void)
{
	atomic_long_dec(&num_poisoned_pages);
}

#else

static inline swp_entry_t make_hwpoison_entry(struct page *page)
{
	return swp_entry(0, 0);
}

static inline int is_hwpoison_entry(swp_entry_t swp)
{
	return 0;
}

static inline void num_poisoned_pages_inc(void)
{
}
#endif

#if defined(CONFIG_MEMORY_FAILURE) || defined(CONFIG_MIGRATION)
static inline int non_swap_entry(swp_entry_t entry)
{
	return swp_type(entry) >= MAX_SWAPFILES;
}
#else
static inline int non_swap_entry(swp_entry_t entry)
{
	return 0;
}
#endif

#endif /* CONFIG_MMU */
#endif /* _LINUX_SWAPOPS_H */
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
a2c16d6c HD	2	#ifndef _LINUX_SWAPOPS_H
	3	#define _LINUX_SWAPOPS_H
	4
	5	#include <linux/radix-tree.h>
187f1882	6	#include <linux/bug.h>
2b740303	7	#include <linux/mm_types.h>
a2c16d6c	8
9b98fa22 CH	9	#ifdef CONFIG_MMU
9b98fa22 CH	10
1da177e4 LT	11	/*
	12	* swapcache pages are stored in the swapper_space radix tree. We want to
	13	* get good packing density in that tree, so the index should be dense in
	14	* the low-order bits.
	15	*
9b15b817	16	* We arrange the `type' and `offset' fields so that `type' is at the seven
e83a9596	17	* high-order bits of the swp_entry_t and `offset' is right-aligned in the
9b15b817 HD	18	* remaining bits. Although `type' itself needs only five bits, we allow for
9b15b817 HD	19	* shmem/tmpfs to shift it all up a further two bits: see swp_to_radix_entry().
1da177e4 LT	20	*
	21	* swp_entry_t's are never stored anywhere in their arch-dependent format.
	22	*/
3159f943 MW	23	#define SWP_TYPE_SHIFT (BITS_PER_XA_VALUE - MAX_SWAPFILES_SHIFT)
3159f943 MW	24	#define SWP_OFFSET_MASK ((1UL << SWP_TYPE_SHIFT) - 1)
1da177e4 LT	25
	26	/*
	27	* Store a type+offset into a swp_entry_t in an arch-independent format
	28	*/
	29	static inline swp_entry_t swp_entry(unsigned long type, pgoff_t offset)
	30	{
	31	swp_entry_t ret;
	32
3159f943	33	ret.val = (type << SWP_TYPE_SHIFT) \| (offset & SWP_OFFSET_MASK);
1da177e4 LT	34	return ret;
	35	}
	36
	37	/*
	38	* Extract the `type' field from a swp_entry_t. The swp_entry_t is in
	39	* arch-independent format
	40	*/
	41	static inline unsigned swp_type(swp_entry_t entry)
	42	{
3159f943	43	return (entry.val >> SWP_TYPE_SHIFT);
1da177e4 LT	44	}
	45
	46	/*
	47	* Extract the `offset' field from a swp_entry_t. The swp_entry_t is in
	48	* arch-independent format
	49	*/
	50	static inline pgoff_t swp_offset(swp_entry_t entry)
	51	{
3159f943	52	return entry.val & SWP_OFFSET_MASK;
1da177e4 LT	53	}
1da177e4 LT	54
698dd4ba MM	55	/* check whether a pte points to a swap entry */
	56	static inline int is_swap_pte(pte_t pte)
	57	{
21d9ee3e	58	return !pte_none(pte) && !pte_present(pte);
698dd4ba MM	59	}
698dd4ba MM	60
1da177e4 LT	61	/*
	62	* Convert the arch-dependent pte representation of a swp_entry_t into an
	63	* arch-independent swp_entry_t.
	64	*/
	65	static inline swp_entry_t pte_to_swp_entry(pte_t pte)
	66	{
	67	swp_entry_t arch_entry;
	68
179ef71c CG	69	if (pte_swp_soft_dirty(pte))
179ef71c CG	70	pte = pte_swp_clear_soft_dirty(pte);
1da177e4 LT	71	arch_entry = __pte_to_swp_entry(pte);
	72	return swp_entry(__swp_type(arch_entry), __swp_offset(arch_entry));
	73	}
	74
	75	/*
	76	* Convert the arch-independent representation of a swp_entry_t into the
	77	* arch-dependent pte representation.
	78	*/
	79	static inline pte_t swp_entry_to_pte(swp_entry_t entry)
	80	{
	81	swp_entry_t arch_entry;
	82
	83	arch_entry = __swp_entry(swp_type(entry), swp_offset(entry));
1da177e4 LT	84	return __swp_entry_to_pte(arch_entry);
1da177e4 LT	85	}
0697212a	86
a2c16d6c HD	87	static inline swp_entry_t radix_to_swp_entry(void *arg)
	88	{
	89	swp_entry_t entry;
	90
3159f943	91	entry.val = xa_to_value(arg);
a2c16d6c HD	92	return entry;
	93	}
	94
	95	static inline void *swp_to_radix_entry(swp_entry_t entry)
	96	{
3159f943	97	return xa_mk_value(entry.val);
a2c16d6c HD	98	}
a2c16d6c HD	99
5042db43 JG	100	#if IS_ENABLED(CONFIG_DEVICE_PRIVATE)
	101	static inline swp_entry_t make_device_private_entry(struct page *page, bool write)
	102	{
	103	return swp_entry(write ? SWP_DEVICE_WRITE : SWP_DEVICE_READ,
	104	page_to_pfn(page));
	105	}
	106
	107	static inline bool is_device_private_entry(swp_entry_t entry)
	108	{
	109	int type = swp_type(entry);
	110	return type == SWP_DEVICE_READ \|\| type == SWP_DEVICE_WRITE;
	111	}
	112
	113	static inline void make_device_private_entry_read(swp_entry_t *entry)
	114	{
	115	entry = swp_entry(SWP_DEVICE_READ, swp_offset(entry));
	116	}
	117
	118	static inline bool is_write_device_private_entry(swp_entry_t entry)
	119	{
	120	return unlikely(swp_type(entry) == SWP_DEVICE_WRITE);
	121	}
	122
0d665e7b KS	123	static inline unsigned long device_private_entry_to_pfn(swp_entry_t entry)
	124	{
	125	return swp_offset(entry);
	126	}
	127
5042db43 JG	128	static inline struct page *device_private_entry_to_page(swp_entry_t entry)
	129	{
	130	return pfn_to_page(swp_offset(entry));
	131	}
5042db43 JG	132	#else /* CONFIG_DEVICE_PRIVATE */
	133	static inline swp_entry_t make_device_private_entry(struct page *page, bool write)
	134	{
	135	return swp_entry(0, 0);
	136	}
	137
	138	static inline void make_device_private_entry_read(swp_entry_t *entry)
	139	{
	140	}
	141
	142	static inline bool is_device_private_entry(swp_entry_t entry)
	143	{
	144	return false;
	145	}
	146
	147	static inline bool is_write_device_private_entry(swp_entry_t entry)
	148	{
	149	return false;
	150	}
	151
0d665e7b KS	152	static inline unsigned long device_private_entry_to_pfn(swp_entry_t entry)
	153	{
	154	return 0;
	155	}
	156
5042db43 JG	157	static inline struct page *device_private_entry_to_page(swp_entry_t entry)
	158	{
	159	return NULL;
	160	}
5042db43 JG	161	#endif /* CONFIG_DEVICE_PRIVATE */
5042db43 JG	162
0697212a CL	163	#ifdef CONFIG_MIGRATION
	164	static inline swp_entry_t make_migration_entry(struct page *page, int write)
	165	{
616b8371 ZY	166	BUG_ON(!PageLocked(compound_head(page)));
616b8371 ZY	167
0697212a CL	168	return swp_entry(write ? SWP_MIGRATION_WRITE : SWP_MIGRATION_READ,
	169	page_to_pfn(page));
	170	}
	171
	172	static inline int is_migration_entry(swp_entry_t entry)
	173	{
	174	return unlikely(swp_type(entry) == SWP_MIGRATION_READ \|\|
	175	swp_type(entry) == SWP_MIGRATION_WRITE);
	176	}
	177
	178	static inline int is_write_migration_entry(swp_entry_t entry)
	179	{
	180	return unlikely(swp_type(entry) == SWP_MIGRATION_WRITE);
	181	}
	182
0d665e7b KS	183	static inline unsigned long migration_entry_to_pfn(swp_entry_t entry)
	184	{
	185	return swp_offset(entry);
	186	}
	187
0697212a CL	188	static inline struct page *migration_entry_to_page(swp_entry_t entry)
	189	{
	190	struct page *p = pfn_to_page(swp_offset(entry));
	191	/*
	192	* Any use of migration entries may only occur while the
	193	* corresponding page is locked
	194	*/
616b8371	195	BUG_ON(!PageLocked(compound_head(p)));
0697212a CL	196	return p;
	197	}
	198
	199	static inline void make_migration_entry_read(swp_entry_t *entry)
	200	{
	201	entry = swp_entry(SWP_MIGRATION_READ, swp_offset(entry));
	202	}
	203
e66f17ff NH	204	extern void __migration_entry_wait(struct mm_struct mm, pte_t ptep,
e66f17ff NH	205	spinlock_t *ptl);
0697212a CL	206	extern void migration_entry_wait(struct mm_struct mm, pmd_t pmd,
0697212a CL	207	unsigned long address);
cb900f41 KS	208	extern void migration_entry_wait_huge(struct vm_area_struct *vma,
cb900f41 KS	209	struct mm_struct mm, pte_t pte);
0697212a CL	210	#else
	211
	212	#define make_migration_entry(page, write) swp_entry(0, 0)
5ec553a9 AM	213	static inline int is_migration_entry(swp_entry_t swp)
	214	{
	215	return 0;
	216	}
0d665e7b KS	217
	218	static inline unsigned long migration_entry_to_pfn(swp_entry_t entry)
	219	{
	220	return 0;
	221	}
	222
616b8371 ZY	223	static inline struct page *migration_entry_to_page(swp_entry_t entry)
	224	{
	225	return NULL;
	226	}
	227
0697212a	228	static inline void make_migration_entry_read(swp_entry_t *entryp) { }
e66f17ff NH	229	static inline void __migration_entry_wait(struct mm_struct mm, pte_t ptep,
e66f17ff NH	230	spinlock_t *ptl) { }
0697212a CL	231	static inline void migration_entry_wait(struct mm_struct mm, pmd_t pmd,
0697212a CL	232	unsigned long address) { }
cb900f41 KS	233	static inline void migration_entry_wait_huge(struct vm_area_struct *vma,
cb900f41 KS	234	struct mm_struct mm, pte_t pte) { }
0697212a CL	235	static inline int is_write_migration_entry(swp_entry_t entry)
	236	{
	237	return 0;
	238	}
	239
	240	#endif
	241
616b8371 ZY	242	struct page_vma_mapped_walk;
	243
	244	#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
	245	extern void set_pmd_migration_entry(struct page_vma_mapped_walk *pvmw,
	246	struct page *page);
	247
	248	extern void remove_migration_pmd(struct page_vma_mapped_walk *pvmw,
	249	struct page *new);
	250
	251	extern void pmd_migration_entry_wait(struct mm_struct mm, pmd_t pmd);
	252
	253	static inline swp_entry_t pmd_to_swp_entry(pmd_t pmd)
	254	{
	255	swp_entry_t arch_entry;
	256
ab6e3d09 NH	257	if (pmd_swp_soft_dirty(pmd))
ab6e3d09 NH	258	pmd = pmd_swp_clear_soft_dirty(pmd);
616b8371 ZY	259	arch_entry = __pmd_to_swp_entry(pmd);
	260	return swp_entry(__swp_type(arch_entry), __swp_offset(arch_entry));
	261	}
	262
	263	static inline pmd_t swp_entry_to_pmd(swp_entry_t entry)
	264	{
	265	swp_entry_t arch_entry;
	266
	267	arch_entry = __swp_entry(swp_type(entry), swp_offset(entry));
	268	return __swp_entry_to_pmd(arch_entry);
	269	}
	270
	271	static inline int is_pmd_migration_entry(pmd_t pmd)
	272	{
	273	return !pmd_present(pmd) && is_migration_entry(pmd_to_swp_entry(pmd));
	274	}
	275	#else
	276	static inline void set_pmd_migration_entry(struct page_vma_mapped_walk *pvmw,
	277	struct page *page)
	278	{
	279	BUILD_BUG();
	280	}
	281
	282	static inline void remove_migration_pmd(struct page_vma_mapped_walk *pvmw,
	283	struct page *new)
	284	{
	285	BUILD_BUG();
	286	}
	287
	288	static inline void pmd_migration_entry_wait(struct mm_struct m, pmd_t p) { }
	289
	290	static inline swp_entry_t pmd_to_swp_entry(pmd_t pmd)
	291	{
	292	return swp_entry(0, 0);
	293	}
	294
	295	static inline pmd_t swp_entry_to_pmd(swp_entry_t entry)
	296	{
	297	return __pmd(0);
	298	}
	299
	300	static inline int is_pmd_migration_entry(pmd_t pmd)
	301	{
	302	return 0;
	303	}
	304	#endif
	305
a7420aa5	306	#ifdef CONFIG_MEMORY_FAILURE
8e30456b NH	307
	308	extern atomic_long_t num_poisoned_pages __read_mostly;
	309
a7420aa5 AK	310	/*
	311	* Support for hardware poisoned pages
	312	*/
	313	static inline swp_entry_t make_hwpoison_entry(struct page *page)
	314	{
	315	BUG_ON(!PageLocked(page));
	316	return swp_entry(SWP_HWPOISON, page_to_pfn(page));
	317	}
	318
	319	static inline int is_hwpoison_entry(swp_entry_t entry)
	320	{
	321	return swp_type(entry) == SWP_HWPOISON;
	322	}
8e30456b NH	323
	324	static inline void num_poisoned_pages_inc(void)
	325	{
	326	atomic_long_inc(&num_poisoned_pages);
	327	}
	328
	329	static inline void num_poisoned_pages_dec(void)
	330	{
	331	atomic_long_dec(&num_poisoned_pages);
	332	}
	333
a7420aa5 AK	334	#else
	335
	336	static inline swp_entry_t make_hwpoison_entry(struct page *page)
	337	{
	338	return swp_entry(0, 0);
	339	}
	340
	341	static inline int is_hwpoison_entry(swp_entry_t swp)
	342	{
	343	return 0;
	344	}
da1b13cc	345
da1b13cc WL	346	static inline void num_poisoned_pages_inc(void)
	347	{
	348	}
a7420aa5 AK	349	#endif
	350
	351	#if defined(CONFIG_MEMORY_FAILURE) \|\| defined(CONFIG_MIGRATION)
	352	static inline int non_swap_entry(swp_entry_t entry)
	353	{
	354	return swp_type(entry) >= MAX_SWAPFILES;
	355	}
	356	#else
	357	static inline int non_swap_entry(swp_entry_t entry)
	358	{
	359	return 0;
	360	}
	361	#endif
a2c16d6c	362
9b98fa22	363	#endif /* CONFIG_MMU */
a2c16d6c	364	#endif /* _LINUX_SWAPOPS_H */