687 lines
21 KiB
C
687 lines
21 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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#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/atomic.h>
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#include <linux/page-flags.h>
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#include <asm/page.h>
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struct notifier_block;
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struct bio;
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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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#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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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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* 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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* 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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* Unaddressable device memory support. See include/linux/hmm.h and
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* Documentation/vm/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_* entry.
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*/
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#ifdef CONFIG_DEVICE_PRIVATE
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#define SWP_DEVICE_NUM 2
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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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#else
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#define SWP_DEVICE_NUM 0
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#endif
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/*
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* NUMA node memory migration support
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*/
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#ifdef CONFIG_MIGRATION
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#define SWP_MIGRATION_NUM 2
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#define SWP_MIGRATION_READ (MAX_SWAPFILES + SWP_HWPOISON_NUM)
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#define SWP_MIGRATION_WRITE (MAX_SWAPFILES + SWP_HWPOISON_NUM + 1)
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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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* 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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#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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/*
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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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* 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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unsigned long reclaimed_slab;
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};
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#ifdef __KERNEL__
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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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* A swap extent maps a range of a swapfile's PAGE_SIZE pages onto a range of
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* disk blocks. A list 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 list_head list;
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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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* 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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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_FILE = (1 << 7), /* set after swap_activate success */
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SWP_AREA_DISCARD = (1 << 8), /* single-time swap area discards */
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SWP_PAGE_DISCARD = (1 << 9), /* freed swap page-cluster discards */
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SWP_STABLE_WRITES = (1 << 10), /* no overwrite PG_writeback pages */
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SWP_SYNCHRONOUS_IO = (1 << 11), /* synchronous IO is efficient */
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/* add others here before... */
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SWP_SCANNING = (1 << 12), /* refcount in scan_swap_map */
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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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#define SWAP_MAP_MAX 0x3e /* Max duplication count, in first swap_map */
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#define SWAP_MAP_BAD 0x3f /* Note pageblock is bad, in first swap_map */
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#define SWAP_HAS_CACHE 0x40 /* Flag page is cached, in first swap_map */
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#define SWAP_CONT_MAX 0x7f /* Max count, in each swap_map continuation */
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#define COUNT_CONTINUED 0x80 /* See swap_map continuation for full count */
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#define SWAP_MAP_SHMEM 0xbf /* Owned by shmem/tmpfs, in first swap_map */
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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 data field stores next cluster if the cluster is free or cluster usage
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* counter otherwise. The flags field determines if a cluster is free. This is
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* protected by swap_info_struct.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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* and swap_info_struct->swap_map
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* elements correspond to the swap
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* cluster
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*/
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unsigned int data:24;
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unsigned int flags:8;
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};
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#define CLUSTER_FLAG_FREE 1 /* This cluster is free */
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#define CLUSTER_FLAG_NEXT_NULL 2 /* This cluster has no next cluster */
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#define CLUSTER_FLAG_HUGE 4 /* This cluster is backing a transparent huge page */
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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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struct swap_cluster_info index; /* Current cluster index */
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unsigned int next; /* Likely next allocation offset */
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};
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struct swap_cluster_list {
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struct swap_cluster_info head;
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struct swap_cluster_info tail;
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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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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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struct swap_cluster_info *cluster_info; /* cluster info. Only for SSD */
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struct swap_cluster_list free_clusters; /* free clusters list */
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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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struct percpu_cluster __percpu *percpu_cluster; /* per cpu's swap location */
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struct swap_extent *curr_swap_extent;
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struct swap_extent first_swap_extent;
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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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unsigned int old_block_size; /* seldom referenced */
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#ifdef CONFIG_FRONTSWAP
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unsigned long *frontswap_map; /* frontswap in-use, one bit per page */
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atomic_t frontswap_pages; /* frontswap pages in-use counter */
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#endif
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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 swap_cluster_list discard_clusters; /* discard clusters list */
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struct plist_node avail_lists[0]; /*
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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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#ifdef CONFIG_64BIT
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#define SWAP_RA_ORDER_CEILING 5
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#else
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/* Avoid stack overflow, because we need to save part of page table */
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#define SWAP_RA_ORDER_CEILING 3
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#define SWAP_RA_PTE_CACHE_SIZE (1 << SWAP_RA_ORDER_CEILING)
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#endif
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struct vma_swap_readahead {
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unsigned short win;
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unsigned short offset;
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unsigned short nr_pte;
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#ifdef CONFIG_64BIT
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pte_t *ptes;
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#else
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pte_t ptes[SWAP_RA_PTE_CACHE_SIZE];
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#endif
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};
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/* linux/mm/workingset.c */
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void *workingset_eviction(struct address_space *mapping, struct page *page);
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bool workingset_refault(void *shadow);
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void workingset_activation(struct page *page);
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/* Do not use directly, use workingset_lookup_update */
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void workingset_update_node(struct radix_tree_node *node);
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/* Returns workingset_update_node() if the mapping has shadow entries. */
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#define workingset_lookup_update(mapping) \
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({ \
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radix_tree_update_node_t __helper = workingset_update_node; \
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if (dax_mapping(mapping) || shmem_mapping(mapping)) \
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__helper = NULL; \
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__helper; \
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})
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/* linux/mm/page_alloc.c */
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extern unsigned long totalram_pages;
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extern unsigned long totalreserve_pages;
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extern unsigned long nr_free_buffer_pages(void);
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extern unsigned long nr_free_pagecache_pages(void);
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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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/* linux/mm/swap.c */
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extern void lru_cache_add(struct page *);
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extern void lru_cache_add_anon(struct page *page);
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extern void lru_cache_add_file(struct page *page);
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extern void lru_add_page_tail(struct page *page, struct page *page_tail,
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struct lruvec *lruvec, struct list_head *head);
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extern void activate_page(struct page *);
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extern void mark_page_accessed(struct page *);
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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_all(void);
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extern void rotate_reclaimable_page(struct page *page);
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extern void deactivate_file_page(struct page *page);
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extern void mark_page_lazyfree(struct page *page);
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extern void swap_setup(void);
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extern void lru_cache_add_active_or_unevictable(struct page *page,
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struct vm_area_struct *vma);
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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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extern int __isolate_lru_page(struct page *page, isolate_mode_t mode);
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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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bool may_swap);
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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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extern int remove_mapping(struct address_space *mapping, struct page *page);
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extern unsigned long vm_total_pages;
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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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extern int page_evictable(struct page *page);
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extern void check_move_unevictable_pages(struct page **, int nr_pages);
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extern int kswapd_run(int nid);
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extern void kswapd_stop(int nid);
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#ifdef CONFIG_SWAP
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#include <linux/blk_types.h> /* for bio_end_io_t */
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/* linux/mm/page_io.c */
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extern int swap_readpage(struct page *page, bool do_poll);
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extern int swap_writepage(struct page *page, struct writeback_control *wbc);
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extern void end_swap_bio_write(struct bio *bio);
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extern int __swap_writepage(struct page *page, struct writeback_control *wbc,
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bio_end_io_t end_write_func);
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extern int swap_set_page_dirty(struct page *page);
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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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/* linux/mm/swap_state.c */
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/* One swap address space for each 64M swap space */
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#define SWAP_ADDRESS_SPACE_SHIFT 14
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#define SWAP_ADDRESS_SPACE_PAGES (1 << SWAP_ADDRESS_SPACE_SHIFT)
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extern struct address_space *swapper_spaces[];
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#define swap_address_space(entry) \
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(&swapper_spaces[swp_type(entry)][swp_offset(entry) \
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>> SWAP_ADDRESS_SPACE_SHIFT])
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extern unsigned long total_swapcache_pages(void);
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extern void show_swap_cache_info(void);
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extern int add_to_swap(struct page *page);
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extern int add_to_swap_cache(struct page *, swp_entry_t, gfp_t);
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extern int __add_to_swap_cache(struct page *page, swp_entry_t entry);
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extern void __delete_from_swap_cache(struct page *);
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extern void delete_from_swap_cache(struct page *);
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extern void free_page_and_swap_cache(struct page *);
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extern void free_pages_and_swap_cache(struct page **, int);
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extern struct page *lookup_swap_cache(swp_entry_t entry,
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struct vm_area_struct *vma,
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unsigned long addr);
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extern struct page *read_swap_cache_async(swp_entry_t, gfp_t,
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struct vm_area_struct *vma, unsigned long addr,
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bool do_poll);
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extern struct page *__read_swap_cache_async(swp_entry_t, gfp_t,
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struct vm_area_struct *vma, unsigned long addr,
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bool *new_page_allocated);
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extern struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,
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struct vm_fault *vmf);
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extern struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,
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struct vm_fault *vmf);
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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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/* 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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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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extern void si_swapinfo(struct sysinfo *);
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extern swp_entry_t get_swap_page(struct page *page);
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extern void put_swap_page(struct page *page, 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 entry_size);
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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);
|
|
extern int swap_type_of(dev_t, sector_t, struct block_device **);
|
|
extern unsigned int count_swap_pages(int, int);
|
|
extern sector_t map_swap_page(struct page *, struct block_device **);
|
|
extern sector_t swapdev_block(int, pgoff_t);
|
|
extern int page_swapcount(struct page *);
|
|
extern int __swap_count(struct swap_info_struct *si, 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);
|
|
extern bool reuse_swap_page(struct page *, int *);
|
|
extern int try_to_free_swap(struct page *);
|
|
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);
|
|
|
|
#else /* CONFIG_SWAP */
|
|
|
|
static inline int swap_readpage(struct page *page, bool do_poll)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline struct swap_info_struct *swp_swap_info(swp_entry_t entry)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
#define swap_address_space(entry) (NULL)
|
|
#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));
|
|
|
|
static inline void show_swap_cache_info(void)
|
|
{
|
|
}
|
|
|
|
#define free_swap_and_cache(e) ({(is_migration_entry(e) || is_device_private_entry(e));})
|
|
#define swapcache_prepare(e) ({(is_migration_entry(e) || is_device_private_entry(e));})
|
|
|
|
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_page(struct page *page, swp_entry_t swp)
|
|
{
|
|
}
|
|
|
|
static inline struct page *swap_cluster_readahead(swp_entry_t entry,
|
|
gfp_t gfp_mask, struct vm_fault *vmf)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
|
|
struct vm_fault *vmf)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline int swap_writepage(struct page *p, struct writeback_control *wbc)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline struct page *lookup_swap_cache(swp_entry_t swp,
|
|
struct vm_area_struct *vma,
|
|
unsigned long addr)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline int add_to_swap(struct page *page)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int add_to_swap_cache(struct page *page, swp_entry_t entry,
|
|
gfp_t gfp_mask)
|
|
{
|
|
return -1;
|
|
}
|
|
|
|
static inline void __delete_from_swap_cache(struct page *page)
|
|
{
|
|
}
|
|
|
|
static inline void delete_from_swap_cache(struct page *page)
|
|
{
|
|
}
|
|
|
|
static inline int page_swapcount(struct page *page)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline int __swap_count(struct swap_info_struct *si, 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;
|
|
}
|
|
|
|
#define reuse_swap_page(page, total_map_swapcount) \
|
|
(page_trans_huge_mapcount(page, total_map_swapcount) == 1)
|
|
|
|
static inline int try_to_free_swap(struct page *page)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline swp_entry_t get_swap_page(struct page *page)
|
|
{
|
|
swp_entry_t entry;
|
|
entry.val = 0;
|
|
return entry;
|
|
}
|
|
|
|
#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() || !memcg->css.parent)
|
|
return vm_swappiness;
|
|
|
|
return memcg->swappiness;
|
|
}
|
|
#else
|
|
static inline int mem_cgroup_swappiness(struct mem_cgroup *mem)
|
|
{
|
|
return vm_swappiness;
|
|
}
|
|
#endif
|
|
|
|
#if defined(CONFIG_SWAP) && defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
|
|
extern void mem_cgroup_throttle_swaprate(struct mem_cgroup *memcg, int node,
|
|
gfp_t gfp_mask);
|
|
#else
|
|
static inline void mem_cgroup_throttle_swaprate(struct mem_cgroup *memcg,
|
|
int node, gfp_t gfp_mask)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_MEMCG_SWAP
|
|
extern void mem_cgroup_swapout(struct page *page, swp_entry_t entry);
|
|
extern int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry);
|
|
extern void mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages);
|
|
extern long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg);
|
|
extern bool mem_cgroup_swap_full(struct page *page);
|
|
#else
|
|
static inline void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
|
|
{
|
|
}
|
|
|
|
static inline int mem_cgroup_try_charge_swap(struct page *page,
|
|
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 page *page)
|
|
{
|
|
return vm_swap_full();
|
|
}
|
|
#endif
|
|
|
|
#endif /* __KERNEL__*/
|
|
#endif /* _LINUX_SWAP_H */
|