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- /* SPDX-License-Identifier: GPL-2.0 */
- #ifndef _LINUX_SWAP_H
- #define _LINUX_SWAP_H
- #include <linux/spinlock.h>
- #include <linux/linkage.h>
- #include <linux/mmzone.h>
- #include <linux/list.h>
- #include <linux/memcontrol.h>
- #include <linux/sched.h>
- #include <linux/node.h>
- #include <linux/fs.h>
- #include <linux/pagemap.h>
- #include <linux/atomic.h>
- #include <linux/page-flags.h>
- #include <uapi/linux/mempolicy.h>
- #include <asm/page.h>
- struct notifier_block;
- struct bio;
- struct pagevec;
- #define SWAP_FLAG_PREFER 0x8000 /* set if swap priority specified */
- #define SWAP_FLAG_PRIO_MASK 0x7fff
- #define SWAP_FLAG_PRIO_SHIFT 0
- #define SWAP_FLAG_DISCARD 0x10000 /* enable discard for swap */
- #define SWAP_FLAG_DISCARD_ONCE 0x20000 /* discard swap area at swapon-time */
- #define SWAP_FLAG_DISCARD_PAGES 0x40000 /* discard page-clusters after use */
- #define SWAP_FLAGS_VALID (SWAP_FLAG_PRIO_MASK | SWAP_FLAG_PREFER | \
- SWAP_FLAG_DISCARD | SWAP_FLAG_DISCARD_ONCE | \
- SWAP_FLAG_DISCARD_PAGES)
- #define SWAP_BATCH 64
- int kswapd (void *p);
- static inline int current_is_kswapd(void)
- {
- return current->flags & PF_KSWAPD;
- }
- /*
- * MAX_SWAPFILES defines the maximum number of swaptypes: things which can
- * be swapped to. The swap type and the offset into that swap type are
- * encoded into pte's and into pgoff_t's in the swapcache. Using five bits
- * for the type means that the maximum number of swapcache pages is 27 bits
- * on 32-bit-pgoff_t architectures. And that assumes that the architecture packs
- * the type/offset into the pte as 5/27 as well.
- */
- #define MAX_SWAPFILES_SHIFT 5
- /*
- * Use some of the swap files numbers for other purposes. This
- * is a convenient way to hook into the VM to trigger special
- * actions on faults.
- */
- #define SWP_SWAPIN_ERROR_NUM 1
- #define SWP_SWAPIN_ERROR (MAX_SWAPFILES + SWP_HWPOISON_NUM + \
- SWP_MIGRATION_NUM + SWP_DEVICE_NUM + \
- SWP_PTE_MARKER_NUM)
- /*
- * PTE markers are used to persist information onto PTEs that are mapped with
- * file-backed memories. As its name "PTE" hints, it should only be applied to
- * the leaves of pgtables.
- */
- #ifdef CONFIG_PTE_MARKER
- #define SWP_PTE_MARKER_NUM 1
- #define SWP_PTE_MARKER (MAX_SWAPFILES + SWP_HWPOISON_NUM + \
- SWP_MIGRATION_NUM + SWP_DEVICE_NUM)
- #else
- #define SWP_PTE_MARKER_NUM 0
- #endif
- /*
- * Unaddressable device memory support. See include/linux/hmm.h and
- * Documentation/mm/hmm.rst. Short description is we need struct pages for
- * device memory that is unaddressable (inaccessible) by CPU, so that we can
- * migrate part of a process memory to device memory.
- *
- * When a page is migrated from CPU to device, we set the CPU page table entry
- * to a special SWP_DEVICE_{READ|WRITE} entry.
- *
- * When a page is mapped by the device for exclusive access we set the CPU page
- * table entries to special SWP_DEVICE_EXCLUSIVE_* entries.
- */
- #ifdef CONFIG_DEVICE_PRIVATE
- #define SWP_DEVICE_NUM 4
- #define SWP_DEVICE_WRITE (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM)
- #define SWP_DEVICE_READ (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM+1)
- #define SWP_DEVICE_EXCLUSIVE_WRITE (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM+2)
- #define SWP_DEVICE_EXCLUSIVE_READ (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM+3)
- #else
- #define SWP_DEVICE_NUM 0
- #endif
- /*
- * Page migration support.
- *
- * SWP_MIGRATION_READ_EXCLUSIVE is only applicable to anonymous pages and
- * indicates that the referenced (part of) an anonymous page is exclusive to
- * a single process. For SWP_MIGRATION_WRITE, that information is implicit:
- * (part of) an anonymous page that are mapped writable are exclusive to a
- * single process.
- */
- #ifdef CONFIG_MIGRATION
- #define SWP_MIGRATION_NUM 3
- #define SWP_MIGRATION_READ (MAX_SWAPFILES + SWP_HWPOISON_NUM)
- #define SWP_MIGRATION_READ_EXCLUSIVE (MAX_SWAPFILES + SWP_HWPOISON_NUM + 1)
- #define SWP_MIGRATION_WRITE (MAX_SWAPFILES + SWP_HWPOISON_NUM + 2)
- #else
- #define SWP_MIGRATION_NUM 0
- #endif
- /*
- * Handling of hardware poisoned pages with memory corruption.
- */
- #ifdef CONFIG_MEMORY_FAILURE
- #define SWP_HWPOISON_NUM 1
- #define SWP_HWPOISON MAX_SWAPFILES
- #else
- #define SWP_HWPOISON_NUM 0
- #endif
- #define MAX_SWAPFILES \
- ((1 << MAX_SWAPFILES_SHIFT) - SWP_DEVICE_NUM - \
- SWP_MIGRATION_NUM - SWP_HWPOISON_NUM - \
- SWP_PTE_MARKER_NUM - SWP_SWAPIN_ERROR_NUM)
- /*
- * Magic header for a swap area. The first part of the union is
- * what the swap magic looks like for the old (limited to 128MB)
- * swap area format, the second part of the union adds - in the
- * old reserved area - some extra information. Note that the first
- * kilobyte is reserved for boot loader or disk label stuff...
- *
- * Having the magic at the end of the PAGE_SIZE makes detecting swap
- * areas somewhat tricky on machines that support multiple page sizes.
- * For 2.5 we'll probably want to move the magic to just beyond the
- * bootbits...
- */
- union swap_header {
- struct {
- char reserved[PAGE_SIZE - 10];
- char magic[10]; /* SWAP-SPACE or SWAPSPACE2 */
- } magic;
- struct {
- char bootbits[1024]; /* Space for disklabel etc. */
- __u32 version;
- __u32 last_page;
- __u32 nr_badpages;
- unsigned char sws_uuid[16];
- unsigned char sws_volume[16];
- __u32 padding[117];
- __u32 badpages[1];
- } info;
- };
- /*
- * current->reclaim_state points to one of these when a task is running
- * memory reclaim
- */
- struct reclaim_state {
- unsigned long reclaimed_slab;
- #ifdef CONFIG_LRU_GEN
- /* per-thread mm walk data */
- struct lru_gen_mm_walk *mm_walk;
- #endif
- };
- #ifdef __KERNEL__
- struct address_space;
- struct sysinfo;
- struct writeback_control;
- struct zone;
- /*
- * A swap extent maps a range of a swapfile's PAGE_SIZE pages onto a range of
- * disk blocks. A rbtree of swap extents maps the entire swapfile (Where the
- * term `swapfile' refers to either a blockdevice or an IS_REG file). Apart
- * from setup, they're handled identically.
- *
- * We always assume that blocks are of size PAGE_SIZE.
- */
- struct swap_extent {
- struct rb_node rb_node;
- pgoff_t start_page;
- pgoff_t nr_pages;
- sector_t start_block;
- };
- /*
- * Max bad pages in the new format..
- */
- #define MAX_SWAP_BADPAGES \
- ((offsetof(union swap_header, magic.magic) - \
- offsetof(union swap_header, info.badpages)) / sizeof(int))
- enum {
- SWP_USED = (1 << 0), /* is slot in swap_info[] used? */
- SWP_WRITEOK = (1 << 1), /* ok to write to this swap? */
- SWP_DISCARDABLE = (1 << 2), /* blkdev support discard */
- SWP_DISCARDING = (1 << 3), /* now discarding a free cluster */
- SWP_SOLIDSTATE = (1 << 4), /* blkdev seeks are cheap */
- SWP_CONTINUED = (1 << 5), /* swap_map has count continuation */
- SWP_BLKDEV = (1 << 6), /* its a block device */
- SWP_ACTIVATED = (1 << 7), /* set after swap_activate success */
- SWP_FS_OPS = (1 << 8), /* swapfile operations go through fs */
- SWP_AREA_DISCARD = (1 << 9), /* single-time swap area discards */
- SWP_PAGE_DISCARD = (1 << 10), /* freed swap page-cluster discards */
- SWP_STABLE_WRITES = (1 << 11), /* no overwrite PG_writeback pages */
- SWP_SYNCHRONOUS_IO = (1 << 12), /* synchronous IO is efficient */
- /* add others here before... */
- SWP_SCANNING = (1 << 14), /* refcount in scan_swap_map */
- };
- #define SWAP_CLUSTER_MAX 32UL
- #define COMPACT_CLUSTER_MAX SWAP_CLUSTER_MAX
- /* Bit flag in swap_map */
- #define SWAP_HAS_CACHE 0x40 /* Flag page is cached, in first swap_map */
- #define COUNT_CONTINUED 0x80 /* Flag swap_map continuation for full count */
- /* Special value in first swap_map */
- #define SWAP_MAP_MAX 0x3e /* Max count */
- #define SWAP_MAP_BAD 0x3f /* Note page is bad */
- #define SWAP_MAP_SHMEM 0xbf /* Owned by shmem/tmpfs */
- /* Special value in each swap_map continuation */
- #define SWAP_CONT_MAX 0x7f /* Max count */
- /*
- * We use this to track usage of a cluster. A cluster is a block of swap disk
- * space with SWAPFILE_CLUSTER pages long and naturally aligns in disk. All
- * free clusters are organized into a list. We fetch an entry from the list to
- * get a free cluster.
- *
- * The data field stores next cluster if the cluster is free or cluster usage
- * counter otherwise. The flags field determines if a cluster is free. This is
- * protected by swap_info_struct.lock.
- */
- struct swap_cluster_info {
- spinlock_t lock; /*
- * Protect swap_cluster_info fields
- * and swap_info_struct->swap_map
- * elements correspond to the swap
- * cluster
- */
- unsigned int data:24;
- unsigned int flags:8;
- };
- #define CLUSTER_FLAG_FREE 1 /* This cluster is free */
- #define CLUSTER_FLAG_NEXT_NULL 2 /* This cluster has no next cluster */
- #define CLUSTER_FLAG_HUGE 4 /* This cluster is backing a transparent huge page */
- /*
- * We assign a cluster to each CPU, so each CPU can allocate swap entry from
- * its own cluster and swapout sequentially. The purpose is to optimize swapout
- * throughput.
- */
- struct percpu_cluster {
- struct swap_cluster_info index; /* Current cluster index */
- unsigned int next; /* Likely next allocation offset */
- };
- struct swap_cluster_list {
- struct swap_cluster_info head;
- struct swap_cluster_info tail;
- };
- /*
- * The in-memory structure used to track swap areas.
- */
- struct swap_info_struct {
- struct percpu_ref users; /* indicate and keep swap device valid. */
- unsigned long flags; /* SWP_USED etc: see above */
- signed short prio; /* swap priority of this type */
- struct plist_node list; /* entry in swap_active_head */
- signed char type; /* strange name for an index */
- unsigned int max; /* extent of the swap_map */
- unsigned char *swap_map; /* vmalloc'ed array of usage counts */
- struct swap_cluster_info *cluster_info; /* cluster info. Only for SSD */
- struct swap_cluster_list free_clusters; /* free clusters list */
- unsigned int lowest_bit; /* index of first free in swap_map */
- unsigned int highest_bit; /* index of last free in swap_map */
- unsigned int pages; /* total of usable pages of swap */
- unsigned int inuse_pages; /* number of those currently in use */
- unsigned int cluster_next; /* likely index for next allocation */
- unsigned int cluster_nr; /* countdown to next cluster search */
- unsigned int __percpu *cluster_next_cpu; /*percpu index for next allocation */
- struct percpu_cluster __percpu *percpu_cluster; /* per cpu's swap location */
- struct rb_root swap_extent_root;/* root of the swap extent rbtree */
- struct block_device *bdev; /* swap device or bdev of swap file */
- struct file *swap_file; /* seldom referenced */
- unsigned int old_block_size; /* seldom referenced */
- struct completion comp; /* seldom referenced */
- #ifdef CONFIG_FRONTSWAP
- unsigned long *frontswap_map; /* frontswap in-use, one bit per page */
- atomic_t frontswap_pages; /* frontswap pages in-use counter */
- #endif
- spinlock_t lock; /*
- * protect map scan related fields like
- * swap_map, lowest_bit, highest_bit,
- * inuse_pages, cluster_next,
- * cluster_nr, lowest_alloc,
- * highest_alloc, free/discard cluster
- * list. other fields are only changed
- * at swapon/swapoff, so are protected
- * by swap_lock. changing flags need
- * hold this lock and swap_lock. If
- * both locks need hold, hold swap_lock
- * first.
- */
- spinlock_t cont_lock; /*
- * protect swap count continuation page
- * list.
- */
- struct work_struct discard_work; /* discard worker */
- struct swap_cluster_list discard_clusters; /* discard clusters list */
- ANDROID_VENDOR_DATA(1);
- struct plist_node avail_lists[]; /*
- * entries in swap_avail_heads, one
- * entry per node.
- * Must be last as the number of the
- * array is nr_node_ids, which is not
- * a fixed value so have to allocate
- * dynamically.
- * And it has to be an array so that
- * plist_for_each_* can work.
- */
- };
- #ifdef CONFIG_64BIT
- #define SWAP_RA_ORDER_CEILING 5
- #else
- /* Avoid stack overflow, because we need to save part of page table */
- #define SWAP_RA_ORDER_CEILING 3
- #define SWAP_RA_PTE_CACHE_SIZE (1 << SWAP_RA_ORDER_CEILING)
- #endif
- struct vma_swap_readahead {
- unsigned short win;
- unsigned short offset;
- unsigned short nr_pte;
- #ifdef CONFIG_64BIT
- pte_t *ptes;
- #else
- pte_t ptes[SWAP_RA_PTE_CACHE_SIZE];
- #endif
- };
- static inline swp_entry_t folio_swap_entry(struct folio *folio)
- {
- swp_entry_t entry = { .val = page_private(&folio->page) };
- return entry;
- }
- static inline void folio_set_swap_entry(struct folio *folio, swp_entry_t entry)
- {
- folio->private = (void *)entry.val;
- }
- /* linux/mm/workingset.c */
- void workingset_age_nonresident(struct lruvec *lruvec, unsigned long nr_pages);
- void *workingset_eviction(struct folio *folio, struct mem_cgroup *target_memcg);
- void workingset_refault(struct folio *folio, void *shadow);
- void workingset_activation(struct folio *folio);
- /* Only track the nodes of mappings with shadow entries */
- void workingset_update_node(struct xa_node *node);
- extern struct list_lru shadow_nodes;
- #define mapping_set_update(xas, mapping) do { \
- if (!dax_mapping(mapping) && !shmem_mapping(mapping)) { \
- xas_set_update(xas, workingset_update_node); \
- xas_set_lru(xas, &shadow_nodes); \
- } \
- } while (0)
- /* linux/mm/page_alloc.c */
- extern unsigned long totalreserve_pages;
- /* Definition of global_zone_page_state not available yet */
- #define nr_free_pages() global_zone_page_state(NR_FREE_PAGES)
- /* linux/mm/swap.c */
- void lru_note_cost(struct lruvec *lruvec, bool file, unsigned int nr_pages);
- void lru_note_cost_folio(struct folio *);
- void folio_add_lru(struct folio *);
- void folio_add_lru_vma(struct folio *, struct vm_area_struct *);
- void lru_cache_add(struct page *);
- void mark_page_accessed(struct page *);
- void folio_mark_accessed(struct folio *);
- extern atomic_t lru_disable_count;
- static inline bool lru_cache_disabled(void)
- {
- return atomic_read(&lru_disable_count);
- }
- static inline void lru_cache_enable(void)
- {
- atomic_dec(&lru_disable_count);
- }
- extern void lru_cache_disable(void);
- extern void lru_add_drain(void);
- extern void lru_add_drain_cpu(int cpu);
- extern void lru_add_drain_cpu_zone(struct zone *zone);
- extern void lru_add_drain_all(void);
- extern void deactivate_page(struct page *page);
- extern void mark_page_lazyfree(struct page *page);
- extern void swap_setup(void);
- extern void lru_cache_add_inactive_or_unevictable(struct page *page,
- struct vm_area_struct *vma);
- /* linux/mm/vmscan.c */
- extern unsigned long zone_reclaimable_pages(struct zone *zone);
- extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
- gfp_t gfp_mask, nodemask_t *mask);
- #define MEMCG_RECLAIM_MAY_SWAP (1 << 1)
- #define MEMCG_RECLAIM_PROACTIVE (1 << 2)
- extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg,
- unsigned long nr_pages,
- gfp_t gfp_mask,
- unsigned int reclaim_options);
- extern unsigned long mem_cgroup_shrink_node(struct mem_cgroup *mem,
- gfp_t gfp_mask, bool noswap,
- pg_data_t *pgdat,
- unsigned long *nr_scanned);
- extern unsigned long shrink_all_memory(unsigned long nr_pages);
- extern int vm_swappiness;
- long remove_mapping(struct address_space *mapping, struct folio *folio);
- extern unsigned long reclaim_pages(struct list_head *page_list);
- #ifdef CONFIG_NUMA
- extern int node_reclaim_mode;
- extern int sysctl_min_unmapped_ratio;
- extern int sysctl_min_slab_ratio;
- #else
- #define node_reclaim_mode 0
- #endif
- static inline bool node_reclaim_enabled(void)
- {
- /* Is any node_reclaim_mode bit set? */
- return node_reclaim_mode & (RECLAIM_ZONE|RECLAIM_WRITE|RECLAIM_UNMAP);
- }
- void check_move_unevictable_folios(struct folio_batch *fbatch);
- void check_move_unevictable_pages(struct pagevec *pvec);
- extern void kswapd_run(int nid);
- extern void kswapd_stop(int nid);
- #ifdef CONFIG_SWAP
- int add_swap_extent(struct swap_info_struct *sis, unsigned long start_page,
- unsigned long nr_pages, sector_t start_block);
- int generic_swapfile_activate(struct swap_info_struct *, struct file *,
- sector_t *);
- static inline unsigned long total_swapcache_pages(void)
- {
- return global_node_page_state(NR_SWAPCACHE);
- }
- extern void free_swap_cache(struct page *page);
- extern void free_page_and_swap_cache(struct page *);
- extern void free_pages_and_swap_cache(struct page **, int);
- /* linux/mm/swapfile.c */
- extern atomic_long_t nr_swap_pages;
- extern long total_swap_pages;
- extern atomic_t nr_rotate_swap;
- extern bool has_usable_swap(void);
- /* Swap 50% full? Release swapcache more aggressively.. */
- static inline bool vm_swap_full(void)
- {
- return atomic_long_read(&nr_swap_pages) * 2 < total_swap_pages;
- }
- static inline long get_nr_swap_pages(void)
- {
- return atomic_long_read(&nr_swap_pages);
- }
- extern void si_swapinfo(struct sysinfo *);
- swp_entry_t folio_alloc_swap(struct folio *folio);
- bool folio_free_swap(struct folio *folio);
- void put_swap_folio(struct folio *folio, swp_entry_t entry);
- extern swp_entry_t get_swap_page_of_type(int);
- extern int get_swap_pages(int n, swp_entry_t swp_entries[], int entry_size);
- extern int add_swap_count_continuation(swp_entry_t, gfp_t);
- extern void swap_shmem_alloc(swp_entry_t);
- extern int swap_duplicate(swp_entry_t);
- extern int swapcache_prepare(swp_entry_t);
- extern void swap_free(swp_entry_t);
- extern void swapcache_free_entries(swp_entry_t *entries, int n);
- extern int free_swap_and_cache(swp_entry_t);
- int swap_type_of(dev_t device, sector_t offset);
- int find_first_swap(dev_t *device);
- extern unsigned int count_swap_pages(int, int);
- extern sector_t swapdev_block(int, pgoff_t);
- extern int __swap_count(swp_entry_t entry);
- extern int __swp_swapcount(swp_entry_t entry);
- extern int swp_swapcount(swp_entry_t entry);
- extern struct swap_info_struct *page_swap_info(struct page *);
- extern struct swap_info_struct *swp_swap_info(swp_entry_t entry);
- struct backing_dev_info;
- extern int init_swap_address_space(unsigned int type, unsigned long nr_pages);
- extern void exit_swap_address_space(unsigned int type);
- extern struct swap_info_struct *get_swap_device(swp_entry_t entry);
- sector_t swap_page_sector(struct page *page);
- extern sector_t alloc_swapdev_block(int swap);
- static inline void put_swap_device(struct swap_info_struct *si)
- {
- percpu_ref_put(&si->users);
- }
- #else /* CONFIG_SWAP */
- static inline struct swap_info_struct *swp_swap_info(swp_entry_t entry)
- {
- return NULL;
- }
- static inline struct swap_info_struct *get_swap_device(swp_entry_t entry)
- {
- return NULL;
- }
- static inline void put_swap_device(struct swap_info_struct *si)
- {
- }
- #define get_nr_swap_pages() 0L
- #define total_swap_pages 0L
- #define total_swapcache_pages() 0UL
- #define vm_swap_full() 0
- #define si_swapinfo(val) \
- 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));
- /* used to sanity check ptes in zap_pte_range when CONFIG_SWAP=0 */
- #define free_swap_and_cache(e) is_pfn_swap_entry(e)
- static inline void free_swap_cache(struct page *page)
- {
- }
- 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)
- {
- }
- static inline int swap_duplicate(swp_entry_t swp)
- {
- return 0;
- }
- static inline void swap_free(swp_entry_t swp)
- {
- }
- 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 __swp_swapcount(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 */
- #ifdef CONFIG_THP_SWAP
- extern int split_swap_cluster(swp_entry_t entry);
- #else
- static inline int split_swap_cluster(swp_entry_t entry)
- {
- return 0;
- }
- #endif
- #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 vm_swappiness;
- /* root ? */
- if (mem_cgroup_disabled() || mem_cgroup_is_root(memcg))
- return vm_swappiness;
- return memcg->swappiness;
- }
- #else
- static inline int mem_cgroup_swappiness(struct mem_cgroup *mem)
- {
- return vm_swappiness;
- }
- #endif
- #ifdef CONFIG_ZSWAP
- extern u64 zswap_pool_total_size;
- extern atomic_t zswap_stored_pages;
- #endif
- #if defined(CONFIG_SWAP) && defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
- extern void __cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask);
- static inline void cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask)
- {
- if (mem_cgroup_disabled())
- return;
- __cgroup_throttle_swaprate(page, gfp_mask);
- }
- #else
- static inline void cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask)
- {
- }
- #endif
- static inline void folio_throttle_swaprate(struct folio *folio, gfp_t gfp)
- {
- cgroup_throttle_swaprate(&folio->page, gfp);
- }
- #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 */
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