709 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			709 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| #ifndef _LINUX_SWAP_H
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| #define _LINUX_SWAP_H
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| 
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| #include <linux/spinlock.h>
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| #include <linux/linkage.h>
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| #include <linux/mmzone.h>
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| #include <linux/list.h>
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| #include <linux/memcontrol.h>
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| #include <linux/sched.h>
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| #include <linux/node.h>
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| #include <linux/fs.h>
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| #include <linux/pagemap.h>
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| #include <linux/atomic.h>
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| #include <linux/page-flags.h>
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| #include <uapi/linux/mempolicy.h>
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| #include <asm/page.h>
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| 
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| struct notifier_block;
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| 
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| struct bio;
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| 
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| struct pagevec;
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| 
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| #define SWAP_FLAG_PREFER	0x8000	/* set if swap priority specified */
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| #define SWAP_FLAG_PRIO_MASK	0x7fff
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| #define SWAP_FLAG_PRIO_SHIFT	0
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| #define SWAP_FLAG_DISCARD	0x10000 /* enable discard for swap */
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| #define SWAP_FLAG_DISCARD_ONCE	0x20000 /* discard swap area at swapon-time */
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| #define SWAP_FLAG_DISCARD_PAGES 0x40000 /* discard page-clusters after use */
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| 
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| #define SWAP_FLAGS_VALID	(SWAP_FLAG_PRIO_MASK | SWAP_FLAG_PREFER | \
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| 				 SWAP_FLAG_DISCARD | SWAP_FLAG_DISCARD_ONCE | \
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| 				 SWAP_FLAG_DISCARD_PAGES)
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| #define SWAP_BATCH 64
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| 
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| static inline int current_is_kswapd(void)
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| {
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| 	return current->flags & PF_KSWAPD;
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| }
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| 
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| /*
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|  * MAX_SWAPFILES defines the maximum number of swaptypes: things which can
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|  * be swapped to.  The swap type and the offset into that swap type are
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|  * encoded into pte's and into pgoff_t's in the swapcache.  Using five bits
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|  * for the type means that the maximum number of swapcache pages is 27 bits
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|  * on 32-bit-pgoff_t architectures.  And that assumes that the architecture packs
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|  * the type/offset into the pte as 5/27 as well.
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|  */
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| #define MAX_SWAPFILES_SHIFT	5
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| 
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| /*
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|  * Use some of the swap files numbers for other purposes. This
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|  * is a convenient way to hook into the VM to trigger special
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|  * actions on faults.
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|  */
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| 
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| /*
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|  * PTE markers are used to persist information onto PTEs that otherwise
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|  * should be a none pte.  As its name "PTE" hints, it should only be
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|  * applied to the leaves of pgtables.
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|  */
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| #define SWP_PTE_MARKER_NUM 1
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| #define SWP_PTE_MARKER     (MAX_SWAPFILES + SWP_HWPOISON_NUM + \
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| 			    SWP_MIGRATION_NUM + SWP_DEVICE_NUM)
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| 
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| /*
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|  * Unaddressable device memory support. See include/linux/hmm.h and
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|  * Documentation/mm/hmm.rst. Short description is we need struct pages for
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|  * device memory that is unaddressable (inaccessible) by CPU, so that we can
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|  * migrate part of a process memory to device memory.
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|  *
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|  * When a page is migrated from CPU to device, we set the CPU page table entry
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|  * to a special SWP_DEVICE_{READ|WRITE} entry.
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|  *
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|  * When a page is mapped by the device for exclusive access we set the CPU page
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|  * table entries to special SWP_DEVICE_EXCLUSIVE_* entries.
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|  */
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| #ifdef CONFIG_DEVICE_PRIVATE
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| #define SWP_DEVICE_NUM 4
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| #define SWP_DEVICE_WRITE (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM)
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| #define SWP_DEVICE_READ (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM+1)
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| #define SWP_DEVICE_EXCLUSIVE_WRITE (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM+2)
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| #define SWP_DEVICE_EXCLUSIVE_READ (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM+3)
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| #else
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| #define SWP_DEVICE_NUM 0
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| #endif
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| 
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| /*
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|  * Page migration support.
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|  *
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|  * SWP_MIGRATION_READ_EXCLUSIVE is only applicable to anonymous pages and
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|  * indicates that the referenced (part of) an anonymous page is exclusive to
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|  * a single process. For SWP_MIGRATION_WRITE, that information is implicit:
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|  * (part of) an anonymous page that are mapped writable are exclusive to a
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|  * single process.
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|  */
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| #ifdef CONFIG_MIGRATION
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| #define SWP_MIGRATION_NUM 3
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| #define SWP_MIGRATION_READ (MAX_SWAPFILES + SWP_HWPOISON_NUM)
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| #define SWP_MIGRATION_READ_EXCLUSIVE (MAX_SWAPFILES + SWP_HWPOISON_NUM + 1)
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| #define SWP_MIGRATION_WRITE (MAX_SWAPFILES + SWP_HWPOISON_NUM + 2)
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| #else
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| #define SWP_MIGRATION_NUM 0
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| #endif
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| 
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| /*
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|  * Handling of hardware poisoned pages with memory corruption.
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|  */
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| #ifdef CONFIG_MEMORY_FAILURE
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| #define SWP_HWPOISON_NUM 1
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| #define SWP_HWPOISON		MAX_SWAPFILES
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| #else
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| #define SWP_HWPOISON_NUM 0
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| #endif
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| 
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| #define MAX_SWAPFILES \
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| 	((1 << MAX_SWAPFILES_SHIFT) - SWP_DEVICE_NUM - \
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| 	SWP_MIGRATION_NUM - SWP_HWPOISON_NUM - \
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| 	SWP_PTE_MARKER_NUM)
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| 
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| /*
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|  * Magic header for a swap area. The first part of the union is
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|  * what the swap magic looks like for the old (limited to 128MB)
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|  * swap area format, the second part of the union adds - in the
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|  * old reserved area - some extra information. Note that the first
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|  * kilobyte is reserved for boot loader or disk label stuff...
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|  *
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|  * Having the magic at the end of the PAGE_SIZE makes detecting swap
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|  * areas somewhat tricky on machines that support multiple page sizes.
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|  * For 2.5 we'll probably want to move the magic to just beyond the
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|  * bootbits...
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|  */
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| union swap_header {
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| 	struct {
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| 		char reserved[PAGE_SIZE - 10];
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| 		char magic[10];			/* SWAP-SPACE or SWAPSPACE2 */
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| 	} magic;
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| 	struct {
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| 		char		bootbits[1024];	/* Space for disklabel etc. */
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| 		__u32		version;
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| 		__u32		last_page;
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| 		__u32		nr_badpages;
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| 		unsigned char	sws_uuid[16];
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| 		unsigned char	sws_volume[16];
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| 		__u32		padding[117];
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| 		__u32		badpages[1];
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| 	} info;
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| };
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| 
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| /*
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|  * current->reclaim_state points to one of these when a task is running
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|  * memory reclaim
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|  */
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| struct reclaim_state {
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| 	/* pages reclaimed outside of LRU-based reclaim */
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| 	unsigned long reclaimed;
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| #ifdef CONFIG_LRU_GEN
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| 	/* per-thread mm walk data */
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| 	struct lru_gen_mm_walk *mm_walk;
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| #endif
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| };
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| 
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| /*
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|  * mm_account_reclaimed_pages(): account reclaimed pages outside of LRU-based
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|  * reclaim
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|  * @pages: number of pages reclaimed
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|  *
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|  * If the current process is undergoing a reclaim operation, increment the
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|  * number of reclaimed pages by @pages.
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|  */
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| static inline void mm_account_reclaimed_pages(unsigned long pages)
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| {
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| 	if (current->reclaim_state)
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| 		current->reclaim_state->reclaimed += pages;
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| }
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| 
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| #ifdef __KERNEL__
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| 
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| struct address_space;
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| struct sysinfo;
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| struct writeback_control;
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| struct zone;
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| 
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| /*
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|  * A swap extent maps a range of a swapfile's PAGE_SIZE pages onto a range of
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|  * disk blocks.  A rbtree of swap extents maps the entire swapfile (Where the
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|  * term `swapfile' refers to either a blockdevice or an IS_REG file). Apart
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|  * from setup, they're handled identically.
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|  *
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|  * We always assume that blocks are of size PAGE_SIZE.
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|  */
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| struct swap_extent {
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| 	struct rb_node rb_node;
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| 	pgoff_t start_page;
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| 	pgoff_t nr_pages;
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| 	sector_t start_block;
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| };
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| 
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| /*
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|  * Max bad pages in the new format..
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|  */
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| #define MAX_SWAP_BADPAGES \
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| 	((offsetof(union swap_header, magic.magic) - \
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| 	  offsetof(union swap_header, info.badpages)) / sizeof(int))
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| 
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| enum {
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| 	SWP_USED	= (1 << 0),	/* is slot in swap_info[] used? */
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| 	SWP_WRITEOK	= (1 << 1),	/* ok to write to this swap?	*/
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| 	SWP_DISCARDABLE = (1 << 2),	/* blkdev support discard */
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| 	SWP_DISCARDING	= (1 << 3),	/* now discarding a free cluster */
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| 	SWP_SOLIDSTATE	= (1 << 4),	/* blkdev seeks are cheap */
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| 	SWP_CONTINUED	= (1 << 5),	/* swap_map has count continuation */
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| 	SWP_BLKDEV	= (1 << 6),	/* its a block device */
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| 	SWP_ACTIVATED	= (1 << 7),	/* set after swap_activate success */
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| 	SWP_FS_OPS	= (1 << 8),	/* swapfile operations go through fs */
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| 	SWP_AREA_DISCARD = (1 << 9),	/* single-time swap area discards */
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| 	SWP_PAGE_DISCARD = (1 << 10),	/* freed swap page-cluster discards */
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| 	SWP_STABLE_WRITES = (1 << 11),	/* no overwrite PG_writeback pages */
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| 	SWP_SYNCHRONOUS_IO = (1 << 12),	/* synchronous IO is efficient */
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| 					/* add others here before... */
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| 	SWP_SCANNING	= (1 << 14),	/* refcount in scan_swap_map */
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| };
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| 
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| #define SWAP_CLUSTER_MAX 32UL
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| #define COMPACT_CLUSTER_MAX SWAP_CLUSTER_MAX
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| 
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| /* Bit flag in swap_map */
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| #define SWAP_HAS_CACHE	0x40	/* Flag page is cached, in first swap_map */
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| #define COUNT_CONTINUED	0x80	/* Flag swap_map continuation for full count */
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| 
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| /* Special value in first swap_map */
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| #define SWAP_MAP_MAX	0x3e	/* Max count */
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| #define SWAP_MAP_BAD	0x3f	/* Note page is bad */
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| #define SWAP_MAP_SHMEM	0xbf	/* Owned by shmem/tmpfs */
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| 
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| /* Special value in each swap_map continuation */
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| #define SWAP_CONT_MAX	0x7f	/* Max count */
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| 
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| /*
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|  * We use this to track usage of a cluster. A cluster is a block of swap disk
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|  * space with SWAPFILE_CLUSTER pages long and naturally aligns in disk. All
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|  * free clusters are organized into a list. We fetch an entry from the list to
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|  * get a free cluster.
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|  *
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|  * The flags field determines if a cluster is free. This is
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|  * protected by cluster lock.
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|  */
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| struct swap_cluster_info {
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| 	spinlock_t lock;	/*
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| 				 * Protect swap_cluster_info fields
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| 				 * other than list, and swap_info_struct->swap_map
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| 				 * elements corresponding to the swap cluster.
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| 				 */
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| 	u16 count;
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| 	u8 flags;
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| 	u8 order;
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| 	struct list_head list;
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| 	
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| 	RH_KABI_RESERVE(1)
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| };
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| #define CLUSTER_FLAG_FREE 1 /* This cluster is free */
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| #define CLUSTER_FLAG_NONFULL 2 /* This cluster is on nonfull list */
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| #define CLUSTER_FLAG_FRAG 4 /* This cluster is on nonfull list */
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| #define CLUSTER_FLAG_FULL 8 /* This cluster is on full list */
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| 
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| /*
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|  * The first page in the swap file is the swap header, which is always marked
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|  * bad to prevent it from being allocated as an entry. This also prevents the
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|  * cluster to which it belongs being marked free. Therefore 0 is safe to use as
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|  * a sentinel to indicate next is not valid in percpu_cluster.
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|  */
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| #define SWAP_NEXT_INVALID	0
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| 
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| #ifdef CONFIG_THP_SWAP
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| #define SWAP_NR_ORDERS		(PMD_ORDER + 1)
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| #else
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| #define SWAP_NR_ORDERS		1
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| #endif
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| 
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| /*
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|  * We assign a cluster to each CPU, so each CPU can allocate swap entry from
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|  * its own cluster and swapout sequentially. The purpose is to optimize swapout
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|  * throughput.
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|  */
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| struct percpu_cluster {
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| 	unsigned int next[SWAP_NR_ORDERS]; /* Likely next allocation offset */
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| 	RH_KABI_RESERVE(1)
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| 	RH_KABI_RESERVE(2)
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| 	RH_KABI_RESERVE(3)
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| };
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| 
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| /*
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|  * The in-memory structure used to track swap areas.
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|  */
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| struct swap_info_struct {
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| 	struct percpu_ref users;	/* indicate and keep swap device valid. */
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| 	unsigned long	flags;		/* SWP_USED etc: see above */
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| 	signed short	prio;		/* swap priority of this type */
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| 	struct plist_node list;		/* entry in swap_active_head */
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| 	signed char	type;		/* strange name for an index */
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| 	unsigned int	max;		/* extent of the swap_map */
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| 	unsigned char *swap_map;	/* vmalloc'ed array of usage counts */
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| 	unsigned long *zeromap;		/* kvmalloc'ed bitmap to track zero pages */
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| 	struct swap_cluster_info *cluster_info; /* cluster info. Only for SSD */
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| 	struct list_head free_clusters; /* free clusters list */
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| 	struct list_head full_clusters; /* full clusters list */
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| 	struct list_head nonfull_clusters[SWAP_NR_ORDERS];
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| 					/* list of cluster that contains at least one free slot */
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| 	struct list_head frag_clusters[SWAP_NR_ORDERS];
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| 					/* list of cluster that are fragmented or contented */
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| 	unsigned int frag_cluster_nr[SWAP_NR_ORDERS];
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| 	unsigned int lowest_bit;	/* index of first free in swap_map */
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| 	unsigned int highest_bit;	/* index of last free in swap_map */
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| 	unsigned int pages;		/* total of usable pages of swap */
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| 	unsigned int inuse_pages;	/* number of those currently in use */
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| 	unsigned int cluster_next;	/* likely index for next allocation */
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| 	unsigned int cluster_nr;	/* countdown to next cluster search */
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| 	unsigned int __percpu *cluster_next_cpu; /*percpu index for next allocation */
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| 	struct percpu_cluster __percpu *percpu_cluster; /* per cpu's swap location */
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| 	struct rb_root swap_extent_root;/* root of the swap extent rbtree */
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| 	struct block_device *bdev;	/* swap device or bdev of swap file */
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| 	struct file *swap_file;		/* seldom referenced */
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| 	struct completion comp;		/* seldom referenced */
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| 	spinlock_t lock;		/*
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| 					 * protect map scan related fields like
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| 					 * swap_map, lowest_bit, highest_bit,
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| 					 * inuse_pages, cluster_next,
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| 					 * cluster_nr, lowest_alloc,
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| 					 * highest_alloc, free/discard cluster
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| 					 * list. other fields are only changed
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| 					 * at swapon/swapoff, so are protected
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| 					 * by swap_lock. changing flags need
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| 					 * hold this lock and swap_lock. If
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| 					 * both locks need hold, hold swap_lock
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| 					 * first.
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| 					 */
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| 	spinlock_t cont_lock;		/*
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| 					 * protect swap count continuation page
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| 					 * list.
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| 					 */
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| 	struct work_struct discard_work; /* discard worker */
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| 	struct work_struct reclaim_work; /* reclaim worker */
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| 	struct list_head discard_clusters; /* discard clusters list */
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| 	struct plist_node avail_lists[]; /*
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| 					   * entries in swap_avail_heads, one
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| 					   * entry per node.
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| 					   * Must be last as the number of the
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| 					   * array is nr_node_ids, which is not
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| 					   * a fixed value so have to allocate
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| 					   * dynamically.
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| 					   * And it has to be an array so that
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| 					   * plist_for_each_* can work.
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| 					   */
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| };
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| 
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| static inline swp_entry_t page_swap_entry(struct page *page)
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| {
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| 	struct folio *folio = page_folio(page);
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| 	swp_entry_t entry = folio->swap;
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| 
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| 	entry.val += folio_page_idx(folio, page);
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| 	return entry;
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| }
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| 
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| /* linux/mm/workingset.c */
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| bool workingset_test_recent(void *shadow, bool file, bool *workingset,
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| 				bool flush);
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| void workingset_age_nonresident(struct lruvec *lruvec, unsigned long nr_pages);
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| void *workingset_eviction(struct folio *folio, struct mem_cgroup *target_memcg);
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| void workingset_refault(struct folio *folio, void *shadow);
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| void workingset_activation(struct folio *folio);
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| 
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| /* linux/mm/page_alloc.c */
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| extern unsigned long totalreserve_pages;
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| 
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| /* Definition of global_zone_page_state not available yet */
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| #define nr_free_pages() global_zone_page_state(NR_FREE_PAGES)
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| 
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| 
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| /* linux/mm/swap.c */
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| void lru_note_cost(struct lruvec *lruvec, bool file,
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| 		   unsigned int nr_io, unsigned int nr_rotated);
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| void lru_note_cost_refault(struct folio *);
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| void folio_add_lru(struct folio *);
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| void folio_add_lru_vma(struct folio *, struct vm_area_struct *);
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| void mark_page_accessed(struct page *);
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| void folio_mark_accessed(struct folio *);
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| 
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| extern atomic_t lru_disable_count;
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| 
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| static inline bool lru_cache_disabled(void)
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| {
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| 	return atomic_read(&lru_disable_count);
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| }
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| 
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| static inline void lru_cache_enable(void)
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| {
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| 	atomic_dec(&lru_disable_count);
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| }
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| 
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| extern void lru_cache_disable(void);
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| extern void lru_add_drain(void);
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| extern void lru_add_drain_cpu(int cpu);
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| extern void lru_add_drain_cpu_zone(struct zone *zone);
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| extern void lru_add_drain_all(void);
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| void folio_deactivate(struct folio *folio);
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| void folio_mark_lazyfree(struct folio *folio);
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| extern void swap_setup(void);
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| 
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| /* linux/mm/vmscan.c */
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| extern unsigned long zone_reclaimable_pages(struct zone *zone);
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| extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
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| 					gfp_t gfp_mask, nodemask_t *mask);
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| 
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| #define MEMCG_RECLAIM_MAY_SWAP (1 << 1)
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| #define MEMCG_RECLAIM_PROACTIVE (1 << 2)
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| #define MIN_SWAPPINESS 0
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| #define MAX_SWAPPINESS 200
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| extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg,
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| 						  unsigned long nr_pages,
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| 						  gfp_t gfp_mask,
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| 						  unsigned int reclaim_options,
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| 						  int *swappiness);
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| extern unsigned long mem_cgroup_shrink_node(struct mem_cgroup *mem,
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| 						gfp_t gfp_mask, bool noswap,
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| 						pg_data_t *pgdat,
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| 						unsigned long *nr_scanned);
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| extern unsigned long shrink_all_memory(unsigned long nr_pages);
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| extern int vm_swappiness;
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| long remove_mapping(struct address_space *mapping, struct folio *folio);
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| 
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| #ifdef CONFIG_NUMA
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| extern int node_reclaim_mode;
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| extern int sysctl_min_unmapped_ratio;
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| extern int sysctl_min_slab_ratio;
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| #else
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| #define node_reclaim_mode 0
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| #endif
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| 
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| static inline bool node_reclaim_enabled(void)
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| {
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| 	/* Is any node_reclaim_mode bit set? */
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| 	return node_reclaim_mode & (RECLAIM_ZONE|RECLAIM_WRITE|RECLAIM_UNMAP);
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| }
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| 
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| void check_move_unevictable_folios(struct folio_batch *fbatch);
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| 
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| extern void __meminit kswapd_run(int nid);
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| extern void __meminit kswapd_stop(int nid);
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| 
 | |
| #ifdef CONFIG_SWAP
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| 
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| int add_swap_extent(struct swap_info_struct *sis, unsigned long start_page,
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| 		unsigned long nr_pages, sector_t start_block);
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| int generic_swapfile_activate(struct swap_info_struct *, struct file *,
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| 		sector_t *);
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| 
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| static inline unsigned long total_swapcache_pages(void)
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| {
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| 	return global_node_page_state(NR_SWAPCACHE);
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| }
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| 
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| void free_swap_cache(struct folio *folio);
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| void free_page_and_swap_cache(struct page *);
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| void free_pages_and_swap_cache(struct encoded_page **, int);
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| /* linux/mm/swapfile.c */
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| extern atomic_long_t nr_swap_pages;
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| extern long total_swap_pages;
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| extern atomic_t nr_rotate_swap;
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| extern bool has_usable_swap(void);
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| 
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| /* Swap 50% full? Release swapcache more aggressively.. */
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| static inline bool vm_swap_full(void)
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| {
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| 	return atomic_long_read(&nr_swap_pages) * 2 < total_swap_pages;
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| }
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| 
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| static inline long get_nr_swap_pages(void)
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| {
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| 	return atomic_long_read(&nr_swap_pages);
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| }
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| 
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| extern void si_swapinfo(struct sysinfo *);
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| swp_entry_t folio_alloc_swap(struct folio *folio);
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| bool folio_free_swap(struct folio *folio);
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| void put_swap_folio(struct folio *folio, swp_entry_t entry);
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| extern swp_entry_t get_swap_page_of_type(int);
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| extern int get_swap_pages(int n, swp_entry_t swp_entries[], int order);
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| extern int add_swap_count_continuation(swp_entry_t, gfp_t);
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| extern void swap_shmem_alloc(swp_entry_t, int);
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| extern int swap_duplicate(swp_entry_t);
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| extern int swapcache_prepare(swp_entry_t entry, int nr);
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| extern void swap_free_nr(swp_entry_t entry, int nr_pages);
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| extern void swapcache_free_entries(swp_entry_t *entries, int n);
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| extern void free_swap_and_cache_nr(swp_entry_t entry, int nr);
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| int swap_type_of(dev_t device, sector_t offset);
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| int find_first_swap(dev_t *device);
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| extern unsigned int count_swap_pages(int, int);
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| extern sector_t swapdev_block(int, pgoff_t);
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| extern int __swap_count(swp_entry_t entry);
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| extern int swap_swapcount(struct swap_info_struct *si, swp_entry_t entry);
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| extern int swp_swapcount(swp_entry_t entry);
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| struct swap_info_struct *swp_swap_info(swp_entry_t entry);
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| struct backing_dev_info;
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| extern int init_swap_address_space(unsigned int type, unsigned long nr_pages);
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| extern void exit_swap_address_space(unsigned int type);
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| extern struct swap_info_struct *get_swap_device(swp_entry_t entry);
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| sector_t swap_folio_sector(struct folio *folio);
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| 
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| static inline void put_swap_device(struct swap_info_struct *si)
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| {
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| 	percpu_ref_put(&si->users);
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| }
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| 
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| #else /* CONFIG_SWAP */
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| static inline struct swap_info_struct *swp_swap_info(swp_entry_t entry)
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| {
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| 	return NULL;
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| }
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| 
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| static inline struct swap_info_struct *get_swap_device(swp_entry_t entry)
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| {
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| 	return NULL;
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| }
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| 
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| static inline void put_swap_device(struct swap_info_struct *si)
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| {
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| }
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| 
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| #define get_nr_swap_pages()			0L
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| #define total_swap_pages			0L
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| #define total_swapcache_pages()			0UL
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| #define vm_swap_full()				0
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| 
 | |
| #define si_swapinfo(val) \
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| 	do { (val)->freeswap = (val)->totalswap = 0; } while (0)
 | |
| /* only sparc can not include linux/pagemap.h in this file
 | |
|  * so leave put_page and release_pages undeclared... */
 | |
| #define free_page_and_swap_cache(page) \
 | |
| 	put_page(page)
 | |
| #define free_pages_and_swap_cache(pages, nr) \
 | |
| 	release_pages((pages), (nr));
 | |
| 
 | |
| static inline void free_swap_and_cache_nr(swp_entry_t entry, int nr)
 | |
| {
 | |
| }
 | |
| 
 | |
| static inline void free_swap_cache(struct folio *folio)
 | |
| {
 | |
| }
 | |
| 
 | |
| static inline int add_swap_count_continuation(swp_entry_t swp, gfp_t gfp_mask)
 | |
| {
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static inline void swap_shmem_alloc(swp_entry_t swp, int nr)
 | |
| {
 | |
| }
 | |
| 
 | |
| static inline int swap_duplicate(swp_entry_t swp)
 | |
| {
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static inline int swapcache_prepare(swp_entry_t swp, int nr)
 | |
| {
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static inline void swap_free_nr(swp_entry_t entry, int nr_pages)
 | |
| {
 | |
| }
 | |
| 
 | |
| static inline void put_swap_folio(struct folio *folio, swp_entry_t swp)
 | |
| {
 | |
| }
 | |
| 
 | |
| static inline int __swap_count(swp_entry_t entry)
 | |
| {
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static inline int swap_swapcount(struct swap_info_struct *si, swp_entry_t entry)
 | |
| {
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static inline int swp_swapcount(swp_entry_t entry)
 | |
| {
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static inline swp_entry_t folio_alloc_swap(struct folio *folio)
 | |
| {
 | |
| 	swp_entry_t entry;
 | |
| 	entry.val = 0;
 | |
| 	return entry;
 | |
| }
 | |
| 
 | |
| static inline bool folio_free_swap(struct folio *folio)
 | |
| {
 | |
| 	return false;
 | |
| }
 | |
| 
 | |
| static inline int add_swap_extent(struct swap_info_struct *sis,
 | |
| 				  unsigned long start_page,
 | |
| 				  unsigned long nr_pages, sector_t start_block)
 | |
| {
 | |
| 	return -EINVAL;
 | |
| }
 | |
| #endif /* CONFIG_SWAP */
 | |
| 
 | |
| static inline void free_swap_and_cache(swp_entry_t entry)
 | |
| {
 | |
| 	free_swap_and_cache_nr(entry, 1);
 | |
| }
 | |
| 
 | |
| static inline void swap_free(swp_entry_t entry)
 | |
| {
 | |
| 	swap_free_nr(entry, 1);
 | |
| }
 | |
| 
 | |
| #ifdef CONFIG_MEMCG
 | |
| static inline int mem_cgroup_swappiness(struct mem_cgroup *memcg)
 | |
| {
 | |
| 	/* Cgroup2 doesn't have per-cgroup swappiness */
 | |
| 	if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
 | |
| 		return READ_ONCE(vm_swappiness);
 | |
| 
 | |
| 	/* root ? */
 | |
| 	if (mem_cgroup_disabled() || mem_cgroup_is_root(memcg))
 | |
| 		return READ_ONCE(vm_swappiness);
 | |
| 
 | |
| 	return READ_ONCE(memcg->swappiness);
 | |
| }
 | |
| #else
 | |
| static inline int mem_cgroup_swappiness(struct mem_cgroup *mem)
 | |
| {
 | |
| 	return READ_ONCE(vm_swappiness);
 | |
| }
 | |
| #endif
 | |
| 
 | |
| #if defined(CONFIG_SWAP) && defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
 | |
| void __folio_throttle_swaprate(struct folio *folio, gfp_t gfp);
 | |
| static inline void folio_throttle_swaprate(struct folio *folio, gfp_t gfp)
 | |
| {
 | |
| 	if (mem_cgroup_disabled())
 | |
| 		return;
 | |
| 	__folio_throttle_swaprate(folio, gfp);
 | |
| }
 | |
| #else
 | |
| static inline void folio_throttle_swaprate(struct folio *folio, gfp_t gfp)
 | |
| {
 | |
| }
 | |
| #endif
 | |
| 
 | |
| #if defined(CONFIG_MEMCG) && defined(CONFIG_SWAP)
 | |
| void mem_cgroup_swapout(struct folio *folio, swp_entry_t entry);
 | |
| int __mem_cgroup_try_charge_swap(struct folio *folio, swp_entry_t entry);
 | |
| static inline int mem_cgroup_try_charge_swap(struct folio *folio,
 | |
| 		swp_entry_t entry)
 | |
| {
 | |
| 	if (mem_cgroup_disabled())
 | |
| 		return 0;
 | |
| 	return __mem_cgroup_try_charge_swap(folio, entry);
 | |
| }
 | |
| 
 | |
| extern void __mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages);
 | |
| static inline void mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages)
 | |
| {
 | |
| 	if (mem_cgroup_disabled())
 | |
| 		return;
 | |
| 	__mem_cgroup_uncharge_swap(entry, nr_pages);
 | |
| }
 | |
| 
 | |
| extern long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg);
 | |
| extern bool mem_cgroup_swap_full(struct folio *folio);
 | |
| #else
 | |
| static inline void mem_cgroup_swapout(struct folio *folio, swp_entry_t entry)
 | |
| {
 | |
| }
 | |
| 
 | |
| static inline int mem_cgroup_try_charge_swap(struct folio *folio,
 | |
| 					     swp_entry_t entry)
 | |
| {
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static inline void mem_cgroup_uncharge_swap(swp_entry_t entry,
 | |
| 					    unsigned int nr_pages)
 | |
| {
 | |
| }
 | |
| 
 | |
| static inline long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg)
 | |
| {
 | |
| 	return get_nr_swap_pages();
 | |
| }
 | |
| 
 | |
| static inline bool mem_cgroup_swap_full(struct folio *folio)
 | |
| {
 | |
| 	return vm_swap_full();
 | |
| }
 | |
| #endif
 | |
| 
 | |
| #endif /* __KERNEL__*/
 | |
| #endif /* _LINUX_SWAP_H */
 |