]>
Commit | Line | Data |
---|---|---|
b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
1da177e4 LT |
2 | #ifndef _LINUX_SWAP_H |
3 | #define _LINUX_SWAP_H | |
4 | ||
1da177e4 LT |
5 | #include <linux/spinlock.h> |
6 | #include <linux/linkage.h> | |
7 | #include <linux/mmzone.h> | |
8 | #include <linux/list.h> | |
66e1707b | 9 | #include <linux/memcontrol.h> |
1da177e4 | 10 | #include <linux/sched.h> |
af936a16 | 11 | #include <linux/node.h> |
33806f06 | 12 | #include <linux/fs.h> |
4ee60ec1 | 13 | #include <linux/pagemap.h> |
60063497 | 14 | #include <linux/atomic.h> |
c53954a0 | 15 | #include <linux/page-flags.h> |
202e35db | 16 | #include <uapi/linux/mempolicy.h> |
1da177e4 LT |
17 | #include <asm/page.h> |
18 | ||
8bc719d3 MS |
19 | struct notifier_block; |
20 | ||
ab954160 AM |
21 | struct bio; |
22 | ||
64e3d12f KHY |
23 | struct pagevec; |
24 | ||
1da177e4 LT |
25 | #define SWAP_FLAG_PREFER 0x8000 /* set if swap priority specified */ |
26 | #define SWAP_FLAG_PRIO_MASK 0x7fff | |
27 | #define SWAP_FLAG_PRIO_SHIFT 0 | |
dcf6b7dd RA |
28 | #define SWAP_FLAG_DISCARD 0x10000 /* enable discard for swap */ |
29 | #define SWAP_FLAG_DISCARD_ONCE 0x20000 /* discard swap area at swapon-time */ | |
30 | #define SWAP_FLAG_DISCARD_PAGES 0x40000 /* discard page-clusters after use */ | |
1da177e4 | 31 | |
d15cab97 | 32 | #define SWAP_FLAGS_VALID (SWAP_FLAG_PRIO_MASK | SWAP_FLAG_PREFER | \ |
dcf6b7dd RA |
33 | SWAP_FLAG_DISCARD | SWAP_FLAG_DISCARD_ONCE | \ |
34 | SWAP_FLAG_DISCARD_PAGES) | |
36005bae | 35 | #define SWAP_BATCH 64 |
d15cab97 | 36 | |
1da177e4 LT |
37 | static inline int current_is_kswapd(void) |
38 | { | |
39 | return current->flags & PF_KSWAPD; | |
40 | } | |
41 | ||
42 | /* | |
43 | * MAX_SWAPFILES defines the maximum number of swaptypes: things which can | |
44 | * be swapped to. The swap type and the offset into that swap type are | |
45 | * encoded into pte's and into pgoff_t's in the swapcache. Using five bits | |
46 | * for the type means that the maximum number of swapcache pages is 27 bits | |
47 | * on 32-bit-pgoff_t architectures. And that assumes that the architecture packs | |
48 | * the type/offset into the pte as 5/27 as well. | |
49 | */ | |
50 | #define MAX_SWAPFILES_SHIFT 5 | |
a7420aa5 AK |
51 | |
52 | /* | |
53 | * Use some of the swap files numbers for other purposes. This | |
54 | * is a convenient way to hook into the VM to trigger special | |
55 | * actions on faults. | |
56 | */ | |
57 | ||
5042db43 JG |
58 | /* |
59 | * Unaddressable device memory support. See include/linux/hmm.h and | |
ad56b738 | 60 | * Documentation/vm/hmm.rst. Short description is we need struct pages for |
5042db43 JG |
61 | * device memory that is unaddressable (inaccessible) by CPU, so that we can |
62 | * migrate part of a process memory to device memory. | |
63 | * | |
64 | * When a page is migrated from CPU to device, we set the CPU page table entry | |
b756a3b5 AP |
65 | * to a special SWP_DEVICE_{READ|WRITE} entry. |
66 | * | |
67 | * When a page is mapped by the device for exclusive access we set the CPU page | |
68 | * table entries to special SWP_DEVICE_EXCLUSIVE_* entries. | |
5042db43 JG |
69 | */ |
70 | #ifdef CONFIG_DEVICE_PRIVATE | |
b756a3b5 | 71 | #define SWP_DEVICE_NUM 4 |
5042db43 JG |
72 | #define SWP_DEVICE_WRITE (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM) |
73 | #define SWP_DEVICE_READ (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM+1) | |
b756a3b5 AP |
74 | #define SWP_DEVICE_EXCLUSIVE_WRITE (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM+2) |
75 | #define SWP_DEVICE_EXCLUSIVE_READ (MAX_SWAPFILES+SWP_HWPOISON_NUM+SWP_MIGRATION_NUM+3) | |
5042db43 JG |
76 | #else |
77 | #define SWP_DEVICE_NUM 0 | |
78 | #endif | |
79 | ||
a7420aa5 AK |
80 | /* |
81 | * NUMA node memory migration support | |
82 | */ | |
83 | #ifdef CONFIG_MIGRATION | |
84 | #define SWP_MIGRATION_NUM 2 | |
85 | #define SWP_MIGRATION_READ (MAX_SWAPFILES + SWP_HWPOISON_NUM) | |
86 | #define SWP_MIGRATION_WRITE (MAX_SWAPFILES + SWP_HWPOISON_NUM + 1) | |
0697212a | 87 | #else |
a7420aa5 | 88 | #define SWP_MIGRATION_NUM 0 |
0697212a | 89 | #endif |
1da177e4 | 90 | |
a7420aa5 AK |
91 | /* |
92 | * Handling of hardware poisoned pages with memory corruption. | |
93 | */ | |
94 | #ifdef CONFIG_MEMORY_FAILURE | |
95 | #define SWP_HWPOISON_NUM 1 | |
96 | #define SWP_HWPOISON MAX_SWAPFILES | |
97 | #else | |
98 | #define SWP_HWPOISON_NUM 0 | |
99 | #endif | |
100 | ||
101 | #define MAX_SWAPFILES \ | |
5042db43 JG |
102 | ((1 << MAX_SWAPFILES_SHIFT) - SWP_DEVICE_NUM - \ |
103 | SWP_MIGRATION_NUM - SWP_HWPOISON_NUM) | |
a7420aa5 | 104 | |
1da177e4 LT |
105 | /* |
106 | * Magic header for a swap area. The first part of the union is | |
107 | * what the swap magic looks like for the old (limited to 128MB) | |
108 | * swap area format, the second part of the union adds - in the | |
109 | * old reserved area - some extra information. Note that the first | |
110 | * kilobyte is reserved for boot loader or disk label stuff... | |
111 | * | |
112 | * Having the magic at the end of the PAGE_SIZE makes detecting swap | |
113 | * areas somewhat tricky on machines that support multiple page sizes. | |
114 | * For 2.5 we'll probably want to move the magic to just beyond the | |
115 | * bootbits... | |
116 | */ | |
117 | union swap_header { | |
118 | struct { | |
119 | char reserved[PAGE_SIZE - 10]; | |
120 | char magic[10]; /* SWAP-SPACE or SWAPSPACE2 */ | |
121 | } magic; | |
122 | struct { | |
e8f03d02 AD |
123 | char bootbits[1024]; /* Space for disklabel etc. */ |
124 | __u32 version; | |
125 | __u32 last_page; | |
126 | __u32 nr_badpages; | |
127 | unsigned char sws_uuid[16]; | |
128 | unsigned char sws_volume[16]; | |
129 | __u32 padding[117]; | |
130 | __u32 badpages[1]; | |
1da177e4 LT |
131 | } info; |
132 | }; | |
133 | ||
1da177e4 LT |
134 | /* |
135 | * current->reclaim_state points to one of these when a task is running | |
136 | * memory reclaim | |
137 | */ | |
138 | struct reclaim_state { | |
139 | unsigned long reclaimed_slab; | |
140 | }; | |
141 | ||
142 | #ifdef __KERNEL__ | |
143 | ||
144 | struct address_space; | |
145 | struct sysinfo; | |
146 | struct writeback_control; | |
147 | struct zone; | |
148 | ||
149 | /* | |
150 | * A swap extent maps a range of a swapfile's PAGE_SIZE pages onto a range of | |
151 | * disk blocks. A list of swap extents maps the entire swapfile. (Where the | |
152 | * term `swapfile' refers to either a blockdevice or an IS_REG file. Apart | |
153 | * from setup, they're handled identically. | |
154 | * | |
155 | * We always assume that blocks are of size PAGE_SIZE. | |
156 | */ | |
157 | struct swap_extent { | |
4efaceb1 | 158 | struct rb_node rb_node; |
1da177e4 LT |
159 | pgoff_t start_page; |
160 | pgoff_t nr_pages; | |
161 | sector_t start_block; | |
162 | }; | |
163 | ||
164 | /* | |
165 | * Max bad pages in the new format.. | |
166 | */ | |
1da177e4 | 167 | #define MAX_SWAP_BADPAGES \ |
a4046c06 PHS |
168 | ((offsetof(union swap_header, magic.magic) - \ |
169 | offsetof(union swap_header, info.badpages)) / sizeof(int)) | |
1da177e4 LT |
170 | |
171 | enum { | |
172 | SWP_USED = (1 << 0), /* is slot in swap_info[] used? */ | |
173 | SWP_WRITEOK = (1 << 1), /* ok to write to this swap? */ | |
dcf6b7dd | 174 | SWP_DISCARDABLE = (1 << 2), /* blkdev support discard */ |
7992fde7 | 175 | SWP_DISCARDING = (1 << 3), /* now discarding a free cluster */ |
20137a49 | 176 | SWP_SOLIDSTATE = (1 << 4), /* blkdev seeks are cheap */ |
570a335b | 177 | SWP_CONTINUED = (1 << 5), /* swap_map has count continuation */ |
b2725643 | 178 | SWP_BLKDEV = (1 << 6), /* its a block device */ |
bc4ae27d | 179 | SWP_ACTIVATED = (1 << 7), /* set after swap_activate success */ |
32646315 | 180 | SWP_FS_OPS = (1 << 8), /* swapfile operations go through fs */ |
bc4ae27d OS |
181 | SWP_AREA_DISCARD = (1 << 9), /* single-time swap area discards */ |
182 | SWP_PAGE_DISCARD = (1 << 10), /* freed swap page-cluster discards */ | |
183 | SWP_STABLE_WRITES = (1 << 11), /* no overwrite PG_writeback pages */ | |
184 | SWP_SYNCHRONOUS_IO = (1 << 12), /* synchronous IO is efficient */ | |
52b7efdb | 185 | /* add others here before... */ |
eb085574 | 186 | SWP_SCANNING = (1 << 14), /* refcount in scan_swap_map */ |
1da177e4 LT |
187 | }; |
188 | ||
d778df51 | 189 | #define SWAP_CLUSTER_MAX 32UL |
748446bb | 190 | #define COMPACT_CLUSTER_MAX SWAP_CLUSTER_MAX |
1da177e4 | 191 | |
4b4bb6bb | 192 | /* Bit flag in swap_map */ |
570a335b | 193 | #define SWAP_HAS_CACHE 0x40 /* Flag page is cached, in first swap_map */ |
4b4bb6bb WY |
194 | #define COUNT_CONTINUED 0x80 /* Flag swap_map continuation for full count */ |
195 | ||
196 | /* Special value in first swap_map */ | |
197 | #define SWAP_MAP_MAX 0x3e /* Max count */ | |
198 | #define SWAP_MAP_BAD 0x3f /* Note page is bad */ | |
199 | #define SWAP_MAP_SHMEM 0xbf /* Owned by shmem/tmpfs */ | |
200 | ||
201 | /* Special value in each swap_map continuation */ | |
202 | #define SWAP_CONT_MAX 0x7f /* Max count */ | |
253d553b | 203 | |
2a8f9449 SL |
204 | /* |
205 | * We use this to track usage of a cluster. A cluster is a block of swap disk | |
206 | * space with SWAPFILE_CLUSTER pages long and naturally aligns in disk. All | |
207 | * free clusters are organized into a list. We fetch an entry from the list to | |
208 | * get a free cluster. | |
209 | * | |
210 | * The data field stores next cluster if the cluster is free or cluster usage | |
211 | * counter otherwise. The flags field determines if a cluster is free. This is | |
212 | * protected by swap_info_struct.lock. | |
213 | */ | |
214 | struct swap_cluster_info { | |
235b6217 HY |
215 | spinlock_t lock; /* |
216 | * Protect swap_cluster_info fields | |
217 | * and swap_info_struct->swap_map | |
218 | * elements correspond to the swap | |
219 | * cluster | |
220 | */ | |
2a8f9449 SL |
221 | unsigned int data:24; |
222 | unsigned int flags:8; | |
223 | }; | |
224 | #define CLUSTER_FLAG_FREE 1 /* This cluster is free */ | |
225 | #define CLUSTER_FLAG_NEXT_NULL 2 /* This cluster has no next cluster */ | |
e0709829 | 226 | #define CLUSTER_FLAG_HUGE 4 /* This cluster is backing a transparent huge page */ |
2a8f9449 | 227 | |
ebc2a1a6 SL |
228 | /* |
229 | * We assign a cluster to each CPU, so each CPU can allocate swap entry from | |
230 | * its own cluster and swapout sequentially. The purpose is to optimize swapout | |
231 | * throughput. | |
232 | */ | |
233 | struct percpu_cluster { | |
234 | struct swap_cluster_info index; /* Current cluster index */ | |
235 | unsigned int next; /* Likely next allocation offset */ | |
236 | }; | |
237 | ||
6b534915 HY |
238 | struct swap_cluster_list { |
239 | struct swap_cluster_info head; | |
240 | struct swap_cluster_info tail; | |
241 | }; | |
242 | ||
1da177e4 LT |
243 | /* |
244 | * The in-memory structure used to track swap areas. | |
1da177e4 LT |
245 | */ |
246 | struct swap_info_struct { | |
63d8620e | 247 | struct percpu_ref users; /* indicate and keep swap device valid. */ |
efa90a98 HD |
248 | unsigned long flags; /* SWP_USED etc: see above */ |
249 | signed short prio; /* swap priority of this type */ | |
18ab4d4c | 250 | struct plist_node list; /* entry in swap_active_head */ |
efa90a98 | 251 | signed char type; /* strange name for an index */ |
7509765a HD |
252 | unsigned int max; /* extent of the swap_map */ |
253 | unsigned char *swap_map; /* vmalloc'ed array of usage counts */ | |
2a8f9449 | 254 | struct swap_cluster_info *cluster_info; /* cluster info. Only for SSD */ |
6b534915 | 255 | struct swap_cluster_list free_clusters; /* free clusters list */ |
7509765a HD |
256 | unsigned int lowest_bit; /* index of first free in swap_map */ |
257 | unsigned int highest_bit; /* index of last free in swap_map */ | |
258 | unsigned int pages; /* total of usable pages of swap */ | |
259 | unsigned int inuse_pages; /* number of those currently in use */ | |
260 | unsigned int cluster_next; /* likely index for next allocation */ | |
261 | unsigned int cluster_nr; /* countdown to next cluster search */ | |
49070588 | 262 | unsigned int __percpu *cluster_next_cpu; /*percpu index for next allocation */ |
ebc2a1a6 | 263 | struct percpu_cluster __percpu *percpu_cluster; /* per cpu's swap location */ |
4efaceb1 | 264 | struct rb_root swap_extent_root;/* root of the swap extent rbtree */ |
7509765a HD |
265 | struct block_device *bdev; /* swap device or bdev of swap file */ |
266 | struct file *swap_file; /* seldom referenced */ | |
267 | unsigned int old_block_size; /* seldom referenced */ | |
63d8620e | 268 | struct completion comp; /* seldom referenced */ |
38b5faf4 DM |
269 | #ifdef CONFIG_FRONTSWAP |
270 | unsigned long *frontswap_map; /* frontswap in-use, one bit per page */ | |
271 | atomic_t frontswap_pages; /* frontswap pages in-use counter */ | |
272 | #endif | |
ec8acf20 SL |
273 | spinlock_t lock; /* |
274 | * protect map scan related fields like | |
275 | * swap_map, lowest_bit, highest_bit, | |
276 | * inuse_pages, cluster_next, | |
815c2c54 SL |
277 | * cluster_nr, lowest_alloc, |
278 | * highest_alloc, free/discard cluster | |
279 | * list. other fields are only changed | |
280 | * at swapon/swapoff, so are protected | |
281 | * by swap_lock. changing flags need | |
282 | * hold this lock and swap_lock. If | |
283 | * both locks need hold, hold swap_lock | |
284 | * first. | |
ec8acf20 | 285 | */ |
2628bd6f HY |
286 | spinlock_t cont_lock; /* |
287 | * protect swap count continuation page | |
288 | * list. | |
289 | */ | |
815c2c54 | 290 | struct work_struct discard_work; /* discard worker */ |
6b534915 | 291 | struct swap_cluster_list discard_clusters; /* discard clusters list */ |
16c3380f | 292 | struct plist_node avail_lists[]; /* |
66f71da9 AL |
293 | * entries in swap_avail_heads, one |
294 | * entry per node. | |
295 | * Must be last as the number of the | |
296 | * array is nr_node_ids, which is not | |
297 | * a fixed value so have to allocate | |
298 | * dynamically. | |
299 | * And it has to be an array so that | |
300 | * plist_for_each_* can work. | |
301 | */ | |
1da177e4 LT |
302 | }; |
303 | ||
ec560175 HY |
304 | #ifdef CONFIG_64BIT |
305 | #define SWAP_RA_ORDER_CEILING 5 | |
306 | #else | |
307 | /* Avoid stack overflow, because we need to save part of page table */ | |
308 | #define SWAP_RA_ORDER_CEILING 3 | |
309 | #define SWAP_RA_PTE_CACHE_SIZE (1 << SWAP_RA_ORDER_CEILING) | |
310 | #endif | |
311 | ||
312 | struct vma_swap_readahead { | |
313 | unsigned short win; | |
314 | unsigned short offset; | |
315 | unsigned short nr_pte; | |
316 | #ifdef CONFIG_64BIT | |
317 | pte_t *ptes; | |
318 | #else | |
319 | pte_t ptes[SWAP_RA_PTE_CACHE_SIZE]; | |
320 | #endif | |
321 | }; | |
322 | ||
a528910e | 323 | /* linux/mm/workingset.c */ |
31d8fcac | 324 | void workingset_age_nonresident(struct lruvec *lruvec, unsigned long nr_pages); |
b910718a | 325 | void *workingset_eviction(struct page *page, struct mem_cgroup *target_memcg); |
1899ad18 | 326 | void workingset_refault(struct page *page, void *shadow); |
a528910e | 327 | void workingset_activation(struct page *page); |
c7df8ad2 | 328 | |
74d60958 MW |
329 | /* Only track the nodes of mappings with shadow entries */ |
330 | void workingset_update_node(struct xa_node *node); | |
331 | #define mapping_set_update(xas, mapping) do { \ | |
332 | if (!dax_mapping(mapping) && !shmem_mapping(mapping)) \ | |
333 | xas_set_update(xas, workingset_update_node); \ | |
334 | } while (0) | |
a528910e | 335 | |
1da177e4 | 336 | /* linux/mm/page_alloc.c */ |
cb45b0e9 | 337 | extern unsigned long totalreserve_pages; |
ebec3862 | 338 | extern unsigned long nr_free_buffer_pages(void); |
1da177e4 | 339 | |
c41f012a MH |
340 | /* Definition of global_zone_page_state not available yet */ |
341 | #define nr_free_pages() global_zone_page_state(NR_FREE_PAGES) | |
96177299 CL |
342 | |
343 | ||
1da177e4 | 344 | /* linux/mm/swap.c */ |
96f8bf4f JW |
345 | extern void lru_note_cost(struct lruvec *lruvec, bool file, |
346 | unsigned int nr_pages); | |
347 | extern void lru_note_cost_page(struct page *); | |
c53954a0 | 348 | extern void lru_cache_add(struct page *); |
b3c97528 | 349 | extern void mark_page_accessed(struct page *); |
d479960e MK |
350 | |
351 | extern atomic_t lru_disable_count; | |
352 | ||
353 | static inline bool lru_cache_disabled(void) | |
354 | { | |
355 | return atomic_read(&lru_disable_count); | |
356 | } | |
357 | ||
358 | static inline void lru_cache_enable(void) | |
359 | { | |
360 | atomic_dec(&lru_disable_count); | |
361 | } | |
362 | ||
363 | extern void lru_cache_disable(void); | |
1da177e4 | 364 | extern void lru_add_drain(void); |
f0cb3c76 | 365 | extern void lru_add_drain_cpu(int cpu); |
b01b2141 | 366 | extern void lru_add_drain_cpu_zone(struct zone *zone); |
5fbc4616 | 367 | extern void lru_add_drain_all(void); |
ac6aadb2 | 368 | extern void rotate_reclaimable_page(struct page *page); |
cc5993bd | 369 | extern void deactivate_file_page(struct page *page); |
9c276cc6 | 370 | extern void deactivate_page(struct page *page); |
f7ad2a6c | 371 | extern void mark_page_lazyfree(struct page *page); |
1da177e4 LT |
372 | extern void swap_setup(void); |
373 | ||
b518154e | 374 | extern void lru_cache_add_inactive_or_unevictable(struct page *page, |
00501b53 JW |
375 | struct vm_area_struct *vma); |
376 | ||
1da177e4 | 377 | /* linux/mm/vmscan.c */ |
5a1c84b4 | 378 | extern unsigned long zone_reclaimable_pages(struct zone *zone); |
dac1d27b | 379 | extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order, |
327c0e96 | 380 | gfp_t gfp_mask, nodemask_t *mask); |
c2135f7c | 381 | extern bool __isolate_lru_page_prepare(struct page *page, isolate_mode_t mode); |
b70a2a21 JW |
382 | extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg, |
383 | unsigned long nr_pages, | |
384 | gfp_t gfp_mask, | |
385 | bool may_swap); | |
a9dd0a83 | 386 | extern unsigned long mem_cgroup_shrink_node(struct mem_cgroup *mem, |
185efc0f | 387 | gfp_t gfp_mask, bool noswap, |
ef8f2327 | 388 | pg_data_t *pgdat, |
185efc0f | 389 | unsigned long *nr_scanned); |
69e05944 | 390 | extern unsigned long shrink_all_memory(unsigned long nr_pages); |
1da177e4 | 391 | extern int vm_swappiness; |
b20a3503 CL |
392 | extern int remove_mapping(struct address_space *mapping, struct page *page); |
393 | ||
1a4e58cc | 394 | extern unsigned long reclaim_pages(struct list_head *page_list); |
9eeff239 | 395 | #ifdef CONFIG_NUMA |
a5f5f91d | 396 | extern int node_reclaim_mode; |
9614634f | 397 | extern int sysctl_min_unmapped_ratio; |
0ff38490 | 398 | extern int sysctl_min_slab_ratio; |
9eeff239 | 399 | #else |
a5f5f91d | 400 | #define node_reclaim_mode 0 |
9eeff239 CL |
401 | #endif |
402 | ||
202e35db DH |
403 | static inline bool node_reclaim_enabled(void) |
404 | { | |
405 | /* Is any node_reclaim_mode bit set? */ | |
406 | return node_reclaim_mode & (RECLAIM_ZONE|RECLAIM_WRITE|RECLAIM_UNMAP); | |
407 | } | |
408 | ||
64e3d12f | 409 | extern void check_move_unevictable_pages(struct pagevec *pvec); |
af936a16 | 410 | |
3218ae14 | 411 | extern int kswapd_run(int nid); |
8fe23e05 | 412 | extern void kswapd_stop(int nid); |
33398cf2 | 413 | |
1da177e4 | 414 | #ifdef CONFIG_SWAP |
be297968 CH |
415 | |
416 | #include <linux/blk_types.h> /* for bio_end_io_t */ | |
417 | ||
1da177e4 | 418 | /* linux/mm/page_io.c */ |
23955622 | 419 | extern int swap_readpage(struct page *page, bool do_poll); |
1da177e4 | 420 | extern int swap_writepage(struct page *page, struct writeback_control *wbc); |
4246a0b6 | 421 | extern void end_swap_bio_write(struct bio *bio); |
1eec6702 | 422 | extern int __swap_writepage(struct page *page, struct writeback_control *wbc, |
4246a0b6 | 423 | bio_end_io_t end_write_func); |
62c230bc | 424 | extern int swap_set_page_dirty(struct page *page); |
1da177e4 | 425 | |
a509bc1a MG |
426 | int add_swap_extent(struct swap_info_struct *sis, unsigned long start_page, |
427 | unsigned long nr_pages, sector_t start_block); | |
428 | int generic_swapfile_activate(struct swap_info_struct *, struct file *, | |
429 | sector_t *); | |
430 | ||
1da177e4 | 431 | /* linux/mm/swap_state.c */ |
4b3ef9da HY |
432 | /* One swap address space for each 64M swap space */ |
433 | #define SWAP_ADDRESS_SPACE_SHIFT 14 | |
434 | #define SWAP_ADDRESS_SPACE_PAGES (1 << SWAP_ADDRESS_SPACE_SHIFT) | |
435 | extern struct address_space *swapper_spaces[]; | |
436 | #define swap_address_space(entry) \ | |
437 | (&swapper_spaces[swp_type(entry)][swp_offset(entry) \ | |
438 | >> SWAP_ADDRESS_SPACE_SHIFT]) | |
b6038942 SB |
439 | static inline unsigned long total_swapcache_pages(void) |
440 | { | |
441 | return global_node_page_state(NR_SWAPCACHE); | |
442 | } | |
443 | ||
1da177e4 | 444 | extern void show_swap_cache_info(void); |
0f074658 | 445 | extern int add_to_swap(struct page *page); |
aae466b0 | 446 | extern void *get_shadow_from_swap_cache(swp_entry_t entry); |
3852f676 JK |
447 | extern int add_to_swap_cache(struct page *page, swp_entry_t entry, |
448 | gfp_t gfp, void **shadowp); | |
449 | extern void __delete_from_swap_cache(struct page *page, | |
450 | swp_entry_t entry, void *shadow); | |
1da177e4 | 451 | extern void delete_from_swap_cache(struct page *); |
3852f676 JK |
452 | extern void clear_shadow_from_swap_cache(int type, unsigned long begin, |
453 | unsigned long end); | |
f4c4a3f4 | 454 | extern void free_swap_cache(struct page *); |
1da177e4 LT |
455 | extern void free_page_and_swap_cache(struct page *); |
456 | extern void free_pages_and_swap_cache(struct page **, int); | |
ec560175 HY |
457 | extern struct page *lookup_swap_cache(swp_entry_t entry, |
458 | struct vm_area_struct *vma, | |
459 | unsigned long addr); | |
61ef1865 | 460 | struct page *find_get_incore_page(struct address_space *mapping, pgoff_t index); |
02098fea | 461 | extern struct page *read_swap_cache_async(swp_entry_t, gfp_t, |
23955622 SL |
462 | struct vm_area_struct *vma, unsigned long addr, |
463 | bool do_poll); | |
5b999aad DS |
464 | extern struct page *__read_swap_cache_async(swp_entry_t, gfp_t, |
465 | struct vm_area_struct *vma, unsigned long addr, | |
466 | bool *new_page_allocated); | |
e9e9b7ec MK |
467 | extern struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t flag, |
468 | struct vm_fault *vmf); | |
469 | extern struct page *swapin_readahead(swp_entry_t entry, gfp_t flag, | |
470 | struct vm_fault *vmf); | |
ec560175 | 471 | |
1da177e4 | 472 | /* linux/mm/swapfile.c */ |
ec8acf20 | 473 | extern atomic_long_t nr_swap_pages; |
1da177e4 | 474 | extern long total_swap_pages; |
81a0298b | 475 | extern atomic_t nr_rotate_swap; |
67afa38e | 476 | extern bool has_usable_swap(void); |
ec8acf20 SL |
477 | |
478 | /* Swap 50% full? Release swapcache more aggressively.. */ | |
479 | static inline bool vm_swap_full(void) | |
480 | { | |
481 | return atomic_long_read(&nr_swap_pages) * 2 < total_swap_pages; | |
482 | } | |
483 | ||
484 | static inline long get_nr_swap_pages(void) | |
485 | { | |
486 | return atomic_long_read(&nr_swap_pages); | |
487 | } | |
488 | ||
1da177e4 | 489 | extern void si_swapinfo(struct sysinfo *); |
38d8b4e6 | 490 | extern swp_entry_t get_swap_page(struct page *page); |
75f6d6d2 | 491 | extern void put_swap_page(struct page *page, swp_entry_t entry); |
910321ea | 492 | extern swp_entry_t get_swap_page_of_type(int); |
5d5e8f19 | 493 | extern int get_swap_pages(int n, swp_entry_t swp_entries[], int entry_size); |
570a335b | 494 | extern int add_swap_count_continuation(swp_entry_t, gfp_t); |
aaa46865 | 495 | extern void swap_shmem_alloc(swp_entry_t); |
570a335b HD |
496 | extern int swap_duplicate(swp_entry_t); |
497 | extern int swapcache_prepare(swp_entry_t); | |
1da177e4 | 498 | extern void swap_free(swp_entry_t); |
7c00bafe | 499 | extern void swapcache_free_entries(swp_entry_t *entries, int n); |
2509ef26 | 500 | extern int free_swap_and_cache(swp_entry_t); |
21bd9005 CH |
501 | int swap_type_of(dev_t device, sector_t offset); |
502 | int find_first_swap(dev_t *device); | |
f577eb30 | 503 | extern unsigned int count_swap_pages(int, int); |
3aef83e0 | 504 | extern sector_t swapdev_block(int, pgoff_t); |
bde05d1c | 505 | extern int page_swapcount(struct page *); |
eb085574 | 506 | extern int __swap_count(swp_entry_t entry); |
e8c26ab6 | 507 | extern int __swp_swapcount(swp_entry_t entry); |
8334b962 | 508 | extern int swp_swapcount(swp_entry_t entry); |
f981c595 | 509 | extern struct swap_info_struct *page_swap_info(struct page *); |
0bcac06f | 510 | extern struct swap_info_struct *swp_swap_info(swp_entry_t entry); |
6d0a07ed | 511 | extern bool reuse_swap_page(struct page *, int *); |
a2c43eed | 512 | extern int try_to_free_swap(struct page *); |
1da177e4 | 513 | struct backing_dev_info; |
4b3ef9da HY |
514 | extern int init_swap_address_space(unsigned int type, unsigned long nr_pages); |
515 | extern void exit_swap_address_space(unsigned int type); | |
eb085574 | 516 | extern struct swap_info_struct *get_swap_device(swp_entry_t entry); |
caf6912f | 517 | sector_t swap_page_sector(struct page *page); |
eb085574 HY |
518 | |
519 | static inline void put_swap_device(struct swap_info_struct *si) | |
520 | { | |
63d8620e | 521 | percpu_ref_put(&si->users); |
eb085574 | 522 | } |
1da177e4 | 523 | |
1da177e4 LT |
524 | #else /* CONFIG_SWAP */ |
525 | ||
0bcac06f MK |
526 | static inline int swap_readpage(struct page *page, bool do_poll) |
527 | { | |
528 | return 0; | |
529 | } | |
530 | ||
531 | static inline struct swap_info_struct *swp_swap_info(swp_entry_t entry) | |
532 | { | |
533 | return NULL; | |
534 | } | |
535 | ||
2799e775 ML |
536 | static inline struct swap_info_struct *get_swap_device(swp_entry_t entry) |
537 | { | |
538 | return NULL; | |
539 | } | |
540 | ||
541 | static inline void put_swap_device(struct swap_info_struct *si) | |
542 | { | |
543 | } | |
544 | ||
2bb6a033 MG |
545 | static inline struct address_space *swap_address_space(swp_entry_t entry) |
546 | { | |
547 | return NULL; | |
548 | } | |
549 | ||
ec8acf20 | 550 | #define get_nr_swap_pages() 0L |
b962716b | 551 | #define total_swap_pages 0L |
33806f06 | 552 | #define total_swapcache_pages() 0UL |
ec8acf20 | 553 | #define vm_swap_full() 0 |
1da177e4 LT |
554 | |
555 | #define si_swapinfo(val) \ | |
556 | do { (val)->freeswap = (val)->totalswap = 0; } while (0) | |
9ae5b3c7 | 557 | /* only sparc can not include linux/pagemap.h in this file |
ea1754a0 | 558 | * so leave put_page and release_pages undeclared... */ |
1da177e4 | 559 | #define free_page_and_swap_cache(page) \ |
09cbfeaf | 560 | put_page(page) |
1da177e4 | 561 | #define free_pages_and_swap_cache(pages, nr) \ |
c6f92f9f | 562 | release_pages((pages), (nr)); |
1da177e4 | 563 | |
f4c4a3f4 HY |
564 | static inline void free_swap_cache(struct page *page) |
565 | { | |
566 | } | |
567 | ||
bd96b9eb CK |
568 | static inline void show_swap_cache_info(void) |
569 | { | |
570 | } | |
571 | ||
af5cdaf8 AP |
572 | /* used to sanity check ptes in zap_pte_range when CONFIG_SWAP=0 */ |
573 | #define free_swap_and_cache(e) is_pfn_swap_entry(e) | |
bd96b9eb | 574 | |
570a335b | 575 | static inline int add_swap_count_continuation(swp_entry_t swp, gfp_t gfp_mask) |
355cfa73 | 576 | { |
570a335b HD |
577 | return 0; |
578 | } | |
579 | ||
aaa46865 HD |
580 | static inline void swap_shmem_alloc(swp_entry_t swp) |
581 | { | |
582 | } | |
583 | ||
570a335b HD |
584 | static inline int swap_duplicate(swp_entry_t swp) |
585 | { | |
586 | return 0; | |
355cfa73 KH |
587 | } |
588 | ||
bd96b9eb CK |
589 | static inline void swap_free(swp_entry_t swp) |
590 | { | |
591 | } | |
592 | ||
75f6d6d2 | 593 | static inline void put_swap_page(struct page *page, swp_entry_t swp) |
cb4b86ba KH |
594 | { |
595 | } | |
596 | ||
e9e9b7ec MK |
597 | static inline struct page *swap_cluster_readahead(swp_entry_t entry, |
598 | gfp_t gfp_mask, struct vm_fault *vmf) | |
bd96b9eb CK |
599 | { |
600 | return NULL; | |
601 | } | |
602 | ||
e9e9b7ec MK |
603 | static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask, |
604 | struct vm_fault *vmf) | |
ec560175 HY |
605 | { |
606 | return NULL; | |
607 | } | |
608 | ||
9fab5619 HD |
609 | static inline int swap_writepage(struct page *p, struct writeback_control *wbc) |
610 | { | |
611 | return 0; | |
612 | } | |
613 | ||
ec560175 HY |
614 | static inline struct page *lookup_swap_cache(swp_entry_t swp, |
615 | struct vm_area_struct *vma, | |
616 | unsigned long addr) | |
bd96b9eb CK |
617 | { |
618 | return NULL; | |
619 | } | |
620 | ||
61ef1865 MWO |
621 | static inline |
622 | struct page *find_get_incore_page(struct address_space *mapping, pgoff_t index) | |
623 | { | |
624 | return find_get_page(mapping, index); | |
625 | } | |
626 | ||
0f074658 | 627 | static inline int add_to_swap(struct page *page) |
60371d97 HD |
628 | { |
629 | return 0; | |
630 | } | |
631 | ||
aae466b0 JK |
632 | static inline void *get_shadow_from_swap_cache(swp_entry_t entry) |
633 | { | |
634 | return NULL; | |
635 | } | |
636 | ||
73b1262f | 637 | static inline int add_to_swap_cache(struct page *page, swp_entry_t entry, |
3852f676 | 638 | gfp_t gfp_mask, void **shadowp) |
bd96b9eb | 639 | { |
73b1262f | 640 | return -1; |
bd96b9eb CK |
641 | } |
642 | ||
4e17ec25 | 643 | static inline void __delete_from_swap_cache(struct page *page, |
3852f676 | 644 | swp_entry_t entry, void *shadow) |
bd96b9eb CK |
645 | { |
646 | } | |
647 | ||
648 | static inline void delete_from_swap_cache(struct page *page) | |
649 | { | |
650 | } | |
651 | ||
3852f676 JK |
652 | static inline void clear_shadow_from_swap_cache(int type, unsigned long begin, |
653 | unsigned long end) | |
654 | { | |
655 | } | |
656 | ||
bde05d1c HD |
657 | static inline int page_swapcount(struct page *page) |
658 | { | |
659 | return 0; | |
660 | } | |
661 | ||
eb085574 | 662 | static inline int __swap_count(swp_entry_t entry) |
aa8d22a1 MK |
663 | { |
664 | return 0; | |
665 | } | |
666 | ||
e8c26ab6 TC |
667 | static inline int __swp_swapcount(swp_entry_t entry) |
668 | { | |
669 | return 0; | |
670 | } | |
671 | ||
8334b962 MK |
672 | static inline int swp_swapcount(swp_entry_t entry) |
673 | { | |
674 | return 0; | |
675 | } | |
676 | ||
ba3c4ce6 HY |
677 | #define reuse_swap_page(page, total_map_swapcount) \ |
678 | (page_trans_huge_mapcount(page, total_map_swapcount) == 1) | |
1da177e4 | 679 | |
a2c43eed | 680 | static inline int try_to_free_swap(struct page *page) |
68a22394 RR |
681 | { |
682 | return 0; | |
683 | } | |
684 | ||
38d8b4e6 | 685 | static inline swp_entry_t get_swap_page(struct page *page) |
1da177e4 LT |
686 | { |
687 | swp_entry_t entry; | |
688 | entry.val = 0; | |
689 | return entry; | |
690 | } | |
691 | ||
1da177e4 | 692 | #endif /* CONFIG_SWAP */ |
6f2cb2f1 | 693 | |
59807685 HY |
694 | #ifdef CONFIG_THP_SWAP |
695 | extern int split_swap_cluster(swp_entry_t entry); | |
696 | #else | |
697 | static inline int split_swap_cluster(swp_entry_t entry) | |
698 | { | |
699 | return 0; | |
700 | } | |
701 | #endif | |
702 | ||
6f2cb2f1 VD |
703 | #ifdef CONFIG_MEMCG |
704 | static inline int mem_cgroup_swappiness(struct mem_cgroup *memcg) | |
705 | { | |
4550c4e1 JW |
706 | /* Cgroup2 doesn't have per-cgroup swappiness */ |
707 | if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) | |
708 | return vm_swappiness; | |
709 | ||
6f2cb2f1 | 710 | /* root ? */ |
59118c42 | 711 | if (mem_cgroup_disabled() || mem_cgroup_is_root(memcg)) |
6f2cb2f1 VD |
712 | return vm_swappiness; |
713 | ||
714 | return memcg->swappiness; | |
715 | } | |
6f2cb2f1 VD |
716 | #else |
717 | static inline int mem_cgroup_swappiness(struct mem_cgroup *mem) | |
718 | { | |
719 | return vm_swappiness; | |
720 | } | |
721 | #endif | |
722 | ||
2cf85583 | 723 | #if defined(CONFIG_SWAP) && defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP) |
6caa6a07 | 724 | extern void cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask); |
2cf85583 | 725 | #else |
6caa6a07 | 726 | static inline void cgroup_throttle_swaprate(struct page *page, gfp_t gfp_mask) |
2cf85583 TH |
727 | { |
728 | } | |
729 | #endif | |
730 | ||
6f2cb2f1 VD |
731 | #ifdef CONFIG_MEMCG_SWAP |
732 | extern void mem_cgroup_swapout(struct page *page, swp_entry_t entry); | |
733 | extern int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry); | |
38d8b4e6 | 734 | extern void mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages); |
d8b38438 | 735 | extern long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg); |
5ccc5aba | 736 | extern bool mem_cgroup_swap_full(struct page *page); |
6f2cb2f1 VD |
737 | #else |
738 | static inline void mem_cgroup_swapout(struct page *page, swp_entry_t entry) | |
739 | { | |
740 | } | |
741 | ||
742 | static inline int mem_cgroup_try_charge_swap(struct page *page, | |
743 | swp_entry_t entry) | |
744 | { | |
745 | return 0; | |
746 | } | |
747 | ||
38d8b4e6 HY |
748 | static inline void mem_cgroup_uncharge_swap(swp_entry_t entry, |
749 | unsigned int nr_pages) | |
6f2cb2f1 VD |
750 | { |
751 | } | |
d8b38438 VD |
752 | |
753 | static inline long mem_cgroup_get_nr_swap_pages(struct mem_cgroup *memcg) | |
754 | { | |
755 | return get_nr_swap_pages(); | |
756 | } | |
5ccc5aba VD |
757 | |
758 | static inline bool mem_cgroup_swap_full(struct page *page) | |
759 | { | |
760 | return vm_swap_full(); | |
761 | } | |
6f2cb2f1 VD |
762 | #endif |
763 | ||
1da177e4 LT |
764 | #endif /* __KERNEL__*/ |
765 | #endif /* _LINUX_SWAP_H */ |