Memory controller: make page_referenced() cgroup aware
[GitHub/LineageOS/android_kernel_samsung_universal7580.git] / include / linux / swap.h
CommitLineData
1da177e4
LT
1#ifndef _LINUX_SWAP_H
2#define _LINUX_SWAP_H
3
1da177e4
LT
4#include <linux/spinlock.h>
5#include <linux/linkage.h>
6#include <linux/mmzone.h>
7#include <linux/list.h>
66e1707b 8#include <linux/memcontrol.h>
1da177e4 9#include <linux/sched.h>
542d1c88 10
1da177e4
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11#include <asm/atomic.h>
12#include <asm/page.h>
13
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14struct notifier_block;
15
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16struct bio;
17
1da177e4
LT
18#define SWAP_FLAG_PREFER 0x8000 /* set if swap priority specified */
19#define SWAP_FLAG_PRIO_MASK 0x7fff
20#define SWAP_FLAG_PRIO_SHIFT 0
21
22static inline int current_is_kswapd(void)
23{
24 return current->flags & PF_KSWAPD;
25}
26
27/*
28 * MAX_SWAPFILES defines the maximum number of swaptypes: things which can
29 * be swapped to. The swap type and the offset into that swap type are
30 * encoded into pte's and into pgoff_t's in the swapcache. Using five bits
31 * for the type means that the maximum number of swapcache pages is 27 bits
32 * on 32-bit-pgoff_t architectures. And that assumes that the architecture packs
33 * the type/offset into the pte as 5/27 as well.
34 */
35#define MAX_SWAPFILES_SHIFT 5
0697212a 36#ifndef CONFIG_MIGRATION
1da177e4 37#define MAX_SWAPFILES (1 << MAX_SWAPFILES_SHIFT)
0697212a
CL
38#else
39/* Use last two entries for page migration swap entries */
40#define MAX_SWAPFILES ((1 << MAX_SWAPFILES_SHIFT)-2)
41#define SWP_MIGRATION_READ MAX_SWAPFILES
42#define SWP_MIGRATION_WRITE (MAX_SWAPFILES + 1)
43#endif
1da177e4
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44
45/*
46 * Magic header for a swap area. The first part of the union is
47 * what the swap magic looks like for the old (limited to 128MB)
48 * swap area format, the second part of the union adds - in the
49 * old reserved area - some extra information. Note that the first
50 * kilobyte is reserved for boot loader or disk label stuff...
51 *
52 * Having the magic at the end of the PAGE_SIZE makes detecting swap
53 * areas somewhat tricky on machines that support multiple page sizes.
54 * For 2.5 we'll probably want to move the magic to just beyond the
55 * bootbits...
56 */
57union swap_header {
58 struct {
59 char reserved[PAGE_SIZE - 10];
60 char magic[10]; /* SWAP-SPACE or SWAPSPACE2 */
61 } magic;
62 struct {
e8f03d02
AD
63 char bootbits[1024]; /* Space for disklabel etc. */
64 __u32 version;
65 __u32 last_page;
66 __u32 nr_badpages;
67 unsigned char sws_uuid[16];
68 unsigned char sws_volume[16];
69 __u32 padding[117];
70 __u32 badpages[1];
1da177e4
LT
71 } info;
72};
73
74 /* A swap entry has to fit into a "unsigned long", as
75 * the entry is hidden in the "index" field of the
76 * swapper address space.
77 */
78typedef struct {
79 unsigned long val;
80} swp_entry_t;
81
82/*
83 * current->reclaim_state points to one of these when a task is running
84 * memory reclaim
85 */
86struct reclaim_state {
87 unsigned long reclaimed_slab;
88};
89
90#ifdef __KERNEL__
91
92struct address_space;
93struct sysinfo;
94struct writeback_control;
95struct zone;
96
97/*
98 * A swap extent maps a range of a swapfile's PAGE_SIZE pages onto a range of
99 * disk blocks. A list of swap extents maps the entire swapfile. (Where the
100 * term `swapfile' refers to either a blockdevice or an IS_REG file. Apart
101 * from setup, they're handled identically.
102 *
103 * We always assume that blocks are of size PAGE_SIZE.
104 */
105struct swap_extent {
106 struct list_head list;
107 pgoff_t start_page;
108 pgoff_t nr_pages;
109 sector_t start_block;
110};
111
112/*
113 * Max bad pages in the new format..
114 */
115#define __swapoffset(x) ((unsigned long)&((union swap_header *)0)->x)
116#define MAX_SWAP_BADPAGES \
117 ((__swapoffset(magic.magic) - __swapoffset(info.badpages)) / sizeof(int))
118
119enum {
120 SWP_USED = (1 << 0), /* is slot in swap_info[] used? */
121 SWP_WRITEOK = (1 << 1), /* ok to write to this swap? */
122 SWP_ACTIVE = (SWP_USED | SWP_WRITEOK),
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HD
123 /* add others here before... */
124 SWP_SCANNING = (1 << 8), /* refcount in scan_swap_map */
1da177e4
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125};
126
127#define SWAP_CLUSTER_MAX 32
128
129#define SWAP_MAP_MAX 0x7fff
130#define SWAP_MAP_BAD 0x8000
131
132/*
133 * The in-memory structure used to track swap areas.
1da177e4
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134 */
135struct swap_info_struct {
136 unsigned int flags;
5d337b91 137 int prio; /* swap priority */
1da177e4
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138 struct file *swap_file;
139 struct block_device *bdev;
140 struct list_head extent_list;
1da177e4
LT
141 struct swap_extent *curr_swap_extent;
142 unsigned old_block_size;
143 unsigned short * swap_map;
144 unsigned int lowest_bit;
145 unsigned int highest_bit;
146 unsigned int cluster_next;
147 unsigned int cluster_nr;
6eb396dc
HD
148 unsigned int pages;
149 unsigned int max;
150 unsigned int inuse_pages;
1da177e4
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151 int next; /* next entry on swap list */
152};
153
154struct swap_list_t {
155 int head; /* head of priority-ordered swapfile list */
156 int next; /* swapfile to be used next */
157};
158
159/* Swap 50% full? Release swapcache more aggressively.. */
160#define vm_swap_full() (nr_swap_pages*2 < total_swap_pages)
161
1da177e4
LT
162/* linux/mm/page_alloc.c */
163extern unsigned long totalram_pages;
cb45b0e9 164extern unsigned long totalreserve_pages;
1da177e4 165extern long nr_swap_pages;
1da177e4
LT
166extern unsigned int nr_free_buffer_pages(void);
167extern unsigned int nr_free_pagecache_pages(void);
168
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CL
169/* Definition of global_page_state not available yet */
170#define nr_free_pages() global_page_state(NR_FREE_PAGES)
171
172
1da177e4
LT
173/* linux/mm/swap.c */
174extern void FASTCALL(lru_cache_add(struct page *));
175extern void FASTCALL(lru_cache_add_active(struct page *));
176extern void FASTCALL(activate_page(struct page *));
177extern void FASTCALL(mark_page_accessed(struct page *));
178extern void lru_add_drain(void);
053837fc 179extern int lru_add_drain_all(void);
1da177e4
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180extern int rotate_reclaimable_page(struct page *page);
181extern void swap_setup(void);
182
183/* linux/mm/vmscan.c */
5ad333eb
AW
184extern unsigned long try_to_free_pages(struct zone **zones, int order,
185 gfp_t gfp_mask);
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BS
186extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem);
187extern int __isolate_lru_page(struct page *page, int mode);
69e05944 188extern unsigned long shrink_all_memory(unsigned long nr_pages);
1da177e4 189extern int vm_swappiness;
b20a3503 190extern int remove_mapping(struct address_space *mapping, struct page *page);
bd1e22b8 191extern long vm_total_pages;
b20a3503 192
9eeff239
CL
193#ifdef CONFIG_NUMA
194extern int zone_reclaim_mode;
9614634f 195extern int sysctl_min_unmapped_ratio;
0ff38490 196extern int sysctl_min_slab_ratio;
9eeff239
CL
197extern int zone_reclaim(struct zone *, gfp_t, unsigned int);
198#else
199#define zone_reclaim_mode 0
200static inline int zone_reclaim(struct zone *z, gfp_t mask, unsigned int order)
201{
202 return 0;
203}
204#endif
205
3218ae14
YG
206extern int kswapd_run(int nid);
207
1da177e4
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208#ifdef CONFIG_MMU
209/* linux/mm/shmem.c */
210extern int shmem_unuse(swp_entry_t entry, struct page *page);
211#endif /* CONFIG_MMU */
212
213extern void swap_unplug_io_fn(struct backing_dev_info *, struct page *);
214
215#ifdef CONFIG_SWAP
216/* linux/mm/page_io.c */
217extern int swap_readpage(struct file *, struct page *);
218extern int swap_writepage(struct page *page, struct writeback_control *wbc);
6712ecf8 219extern void end_swap_bio_read(struct bio *bio, int err);
1da177e4
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220
221/* linux/mm/swap_state.c */
222extern struct address_space swapper_space;
223#define total_swapcache_pages swapper_space.nrpages
224extern void show_swap_cache_info(void);
1480a540 225extern int add_to_swap(struct page *, gfp_t);
73b1262f 226extern int add_to_swap_cache(struct page *, swp_entry_t, gfp_t);
1da177e4
LT
227extern void __delete_from_swap_cache(struct page *);
228extern void delete_from_swap_cache(struct page *);
1da177e4
LT
229extern void free_page_and_swap_cache(struct page *);
230extern void free_pages_and_swap_cache(struct page **, int);
46017e95 231extern struct page *lookup_swap_cache(swp_entry_t);
02098fea 232extern struct page *read_swap_cache_async(swp_entry_t, gfp_t,
46017e95 233 struct vm_area_struct *vma, unsigned long addr);
02098fea 234extern struct page *swapin_readahead(swp_entry_t, gfp_t,
46017e95
HD
235 struct vm_area_struct *vma, unsigned long addr);
236
1da177e4
LT
237/* linux/mm/swapfile.c */
238extern long total_swap_pages;
239extern unsigned int nr_swapfiles;
1da177e4
LT
240extern void si_swapinfo(struct sysinfo *);
241extern swp_entry_t get_swap_page(void);
f577eb30 242extern swp_entry_t get_swap_page_of_type(int);
1da177e4
LT
243extern int swap_duplicate(swp_entry_t);
244extern int valid_swaphandles(swp_entry_t, unsigned long *);
245extern void swap_free(swp_entry_t);
246extern void free_swap_and_cache(swp_entry_t);
7bf23687 247extern int swap_type_of(dev_t, sector_t, struct block_device **);
f577eb30 248extern unsigned int count_swap_pages(int, int);
1da177e4 249extern sector_t map_swap_page(struct swap_info_struct *, pgoff_t);
3aef83e0 250extern sector_t swapdev_block(int, pgoff_t);
1da177e4
LT
251extern struct swap_info_struct *get_swap_info_struct(unsigned);
252extern int can_share_swap_page(struct page *);
253extern int remove_exclusive_swap_page(struct page *);
254struct backing_dev_info;
255
5d337b91 256extern spinlock_t swap_lock;
1da177e4
LT
257
258/* linux/mm/thrash.c */
259extern struct mm_struct * swap_token_mm;
1da177e4
LT
260extern void grab_swap_token(void);
261extern void __put_swap_token(struct mm_struct *);
262
263static inline int has_swap_token(struct mm_struct *mm)
264{
265 return (mm == swap_token_mm);
266}
267
268static inline void put_swap_token(struct mm_struct *mm)
269{
270 if (has_swap_token(mm))
271 __put_swap_token(mm);
272}
273
f7b7fd8f
RR
274static inline void disable_swap_token(void)
275{
276 put_swap_token(swap_token_mm);
277}
278
1da177e4
LT
279#else /* CONFIG_SWAP */
280
281#define total_swap_pages 0
282#define total_swapcache_pages 0UL
283
284#define si_swapinfo(val) \
285 do { (val)->freeswap = (val)->totalswap = 0; } while (0)
9ae5b3c7
OH
286/* only sparc can not include linux/pagemap.h in this file
287 * so leave page_cache_release and release_pages undeclared... */
1da177e4
LT
288#define free_page_and_swap_cache(page) \
289 page_cache_release(page)
290#define free_pages_and_swap_cache(pages, nr) \
291 release_pages((pages), (nr), 0);
292
bd96b9eb
CK
293static inline void show_swap_cache_info(void)
294{
295}
296
297static inline void free_swap_and_cache(swp_entry_t swp)
298{
299}
300
301static inline int swap_duplicate(swp_entry_t swp)
302{
303 return 0;
304}
305
306static inline void swap_free(swp_entry_t swp)
307{
308}
309
02098fea 310static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
bd96b9eb
CK
311 struct vm_area_struct *vma, unsigned long addr)
312{
313 return NULL;
314}
315
316static inline struct page *lookup_swap_cache(swp_entry_t swp)
317{
318 return NULL;
319}
320
e6333fd4 321#define can_share_swap_page(p) (page_mapcount(p) == 1)
bd96b9eb 322
73b1262f
HD
323static inline int add_to_swap_cache(struct page *page, swp_entry_t entry,
324 gfp_t gfp_mask)
bd96b9eb 325{
73b1262f 326 return -1;
bd96b9eb
CK
327}
328
329static inline void __delete_from_swap_cache(struct page *page)
330{
331}
332
333static inline void delete_from_swap_cache(struct page *page)
334{
335}
336
1da177e4
LT
337#define swap_token_default_timeout 0
338
339static inline int remove_exclusive_swap_page(struct page *p)
340{
341 return 0;
342}
343
344static inline swp_entry_t get_swap_page(void)
345{
346 swp_entry_t entry;
347 entry.val = 0;
348 return entry;
349}
350
351/* linux/mm/thrash.c */
352#define put_swap_token(x) do { } while(0)
353#define grab_swap_token() do { } while(0)
354#define has_swap_token(x) 0
f7b7fd8f 355#define disable_swap_token() do { } while(0)
1da177e4
LT
356
357#endif /* CONFIG_SWAP */
358#endif /* __KERNEL__*/
359#endif /* _LINUX_SWAP_H */