Line data Source code
1 : /* SPDX-License-Identifier: GPL-2.0 */
2 : #ifndef _LINUX_MMZONE_H
3 : #define _LINUX_MMZONE_H
4 :
5 : #ifndef __ASSEMBLY__
6 : #ifndef __GENERATING_BOUNDS_H
7 :
8 : #include <linux/spinlock.h>
9 : #include <linux/list.h>
10 : #include <linux/wait.h>
11 : #include <linux/bitops.h>
12 : #include <linux/cache.h>
13 : #include <linux/threads.h>
14 : #include <linux/numa.h>
15 : #include <linux/init.h>
16 : #include <linux/seqlock.h>
17 : #include <linux/nodemask.h>
18 : #include <linux/pageblock-flags.h>
19 : #include <linux/page-flags-layout.h>
20 : #include <linux/atomic.h>
21 : #include <linux/mm_types.h>
22 : #include <linux/page-flags.h>
23 : #include <asm/page.h>
24 :
25 : /* Free memory management - zoned buddy allocator. */
26 : #ifndef CONFIG_FORCE_MAX_ZONEORDER
27 : #define MAX_ORDER 11
28 : #else
29 : #define MAX_ORDER CONFIG_FORCE_MAX_ZONEORDER
30 : #endif
31 : #define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1))
32 :
33 : /*
34 : * PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed
35 : * costly to service. That is between allocation orders which should
36 : * coalesce naturally under reasonable reclaim pressure and those which
37 : * will not.
38 : */
39 : #define PAGE_ALLOC_COSTLY_ORDER 3
40 :
41 : enum migratetype {
42 : MIGRATE_UNMOVABLE,
43 : MIGRATE_MOVABLE,
44 : MIGRATE_RECLAIMABLE,
45 : MIGRATE_PCPTYPES, /* the number of types on the pcp lists */
46 : MIGRATE_HIGHATOMIC = MIGRATE_PCPTYPES,
47 : #ifdef CONFIG_CMA
48 : /*
49 : * MIGRATE_CMA migration type is designed to mimic the way
50 : * ZONE_MOVABLE works. Only movable pages can be allocated
51 : * from MIGRATE_CMA pageblocks and page allocator never
52 : * implicitly change migration type of MIGRATE_CMA pageblock.
53 : *
54 : * The way to use it is to change migratetype of a range of
55 : * pageblocks to MIGRATE_CMA which can be done by
56 : * __free_pageblock_cma() function. What is important though
57 : * is that a range of pageblocks must be aligned to
58 : * MAX_ORDER_NR_PAGES should biggest page be bigger then
59 : * a single pageblock.
60 : */
61 : MIGRATE_CMA,
62 : #endif
63 : #ifdef CONFIG_MEMORY_ISOLATION
64 : MIGRATE_ISOLATE, /* can't allocate from here */
65 : #endif
66 : MIGRATE_TYPES
67 : };
68 :
69 : /* In mm/page_alloc.c; keep in sync also with show_migration_types() there */
70 : extern const char * const migratetype_names[MIGRATE_TYPES];
71 :
72 : #ifdef CONFIG_CMA
73 : # define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA)
74 : # define is_migrate_cma_page(_page) (get_pageblock_migratetype(_page) == MIGRATE_CMA)
75 : #else
76 : # define is_migrate_cma(migratetype) false
77 : # define is_migrate_cma_page(_page) false
78 : #endif
79 :
80 0 : static inline bool is_migrate_movable(int mt)
81 : {
82 0 : return is_migrate_cma(mt) || mt == MIGRATE_MOVABLE;
83 : }
84 :
85 : #define for_each_migratetype_order(order, type) \
86 : for (order = 0; order < MAX_ORDER; order++) \
87 : for (type = 0; type < MIGRATE_TYPES; type++)
88 :
89 : extern int page_group_by_mobility_disabled;
90 :
91 : #define MIGRATETYPE_MASK ((1UL << PB_migratetype_bits) - 1)
92 :
93 : #define get_pageblock_migratetype(page) \
94 : get_pfnblock_flags_mask(page, page_to_pfn(page), MIGRATETYPE_MASK)
95 :
96 : struct free_area {
97 : struct list_head free_list[MIGRATE_TYPES];
98 : unsigned long nr_free;
99 : };
100 :
101 143685 : static inline struct page *get_page_from_free_area(struct free_area *area,
102 : int migratetype)
103 : {
104 143685 : return list_first_entry_or_null(&area->free_list[migratetype],
105 : struct page, lru);
106 : }
107 :
108 30542 : static inline bool free_area_empty(struct free_area *area, int migratetype)
109 : {
110 30542 : return list_empty(&area->free_list[migratetype]);
111 : }
112 :
113 : struct pglist_data;
114 :
115 : /*
116 : * Add a wild amount of padding here to ensure datas fall into separate
117 : * cachelines. There are very few zone structures in the machine, so space
118 : * consumption is not a concern here.
119 : */
120 : #if defined(CONFIG_SMP)
121 : struct zone_padding {
122 : char x[0];
123 : } ____cacheline_internodealigned_in_smp;
124 : #define ZONE_PADDING(name) struct zone_padding name;
125 : #else
126 : #define ZONE_PADDING(name)
127 : #endif
128 :
129 : #ifdef CONFIG_NUMA
130 : enum numa_stat_item {
131 : NUMA_HIT, /* allocated in intended node */
132 : NUMA_MISS, /* allocated in non intended node */
133 : NUMA_FOREIGN, /* was intended here, hit elsewhere */
134 : NUMA_INTERLEAVE_HIT, /* interleaver preferred this zone */
135 : NUMA_LOCAL, /* allocation from local node */
136 : NUMA_OTHER, /* allocation from other node */
137 : NR_VM_NUMA_STAT_ITEMS
138 : };
139 : #else
140 : #define NR_VM_NUMA_STAT_ITEMS 0
141 : #endif
142 :
143 : enum zone_stat_item {
144 : /* First 128 byte cacheline (assuming 64 bit words) */
145 : NR_FREE_PAGES,
146 : NR_ZONE_LRU_BASE, /* Used only for compaction and reclaim retry */
147 : NR_ZONE_INACTIVE_ANON = NR_ZONE_LRU_BASE,
148 : NR_ZONE_ACTIVE_ANON,
149 : NR_ZONE_INACTIVE_FILE,
150 : NR_ZONE_ACTIVE_FILE,
151 : NR_ZONE_UNEVICTABLE,
152 : NR_ZONE_WRITE_PENDING, /* Count of dirty, writeback and unstable pages */
153 : NR_MLOCK, /* mlock()ed pages found and moved off LRU */
154 : /* Second 128 byte cacheline */
155 : NR_BOUNCE,
156 : #if IS_ENABLED(CONFIG_ZSMALLOC)
157 : NR_ZSPAGES, /* allocated in zsmalloc */
158 : #endif
159 : NR_FREE_CMA_PAGES,
160 : NR_VM_ZONE_STAT_ITEMS };
161 :
162 : enum node_stat_item {
163 : NR_LRU_BASE,
164 : NR_INACTIVE_ANON = NR_LRU_BASE, /* must match order of LRU_[IN]ACTIVE */
165 : NR_ACTIVE_ANON, /* " " " " " */
166 : NR_INACTIVE_FILE, /* " " " " " */
167 : NR_ACTIVE_FILE, /* " " " " " */
168 : NR_UNEVICTABLE, /* " " " " " */
169 : NR_SLAB_RECLAIMABLE_B,
170 : NR_SLAB_UNRECLAIMABLE_B,
171 : NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */
172 : NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */
173 : WORKINGSET_NODES,
174 : WORKINGSET_REFAULT_BASE,
175 : WORKINGSET_REFAULT_ANON = WORKINGSET_REFAULT_BASE,
176 : WORKINGSET_REFAULT_FILE,
177 : WORKINGSET_ACTIVATE_BASE,
178 : WORKINGSET_ACTIVATE_ANON = WORKINGSET_ACTIVATE_BASE,
179 : WORKINGSET_ACTIVATE_FILE,
180 : WORKINGSET_RESTORE_BASE,
181 : WORKINGSET_RESTORE_ANON = WORKINGSET_RESTORE_BASE,
182 : WORKINGSET_RESTORE_FILE,
183 : WORKINGSET_NODERECLAIM,
184 : NR_ANON_MAPPED, /* Mapped anonymous pages */
185 : NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
186 : only modified from process context */
187 : NR_FILE_PAGES,
188 : NR_FILE_DIRTY,
189 : NR_WRITEBACK,
190 : NR_WRITEBACK_TEMP, /* Writeback using temporary buffers */
191 : NR_SHMEM, /* shmem pages (included tmpfs/GEM pages) */
192 : NR_SHMEM_THPS,
193 : NR_SHMEM_PMDMAPPED,
194 : NR_FILE_THPS,
195 : NR_FILE_PMDMAPPED,
196 : NR_ANON_THPS,
197 : NR_VMSCAN_WRITE,
198 : NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */
199 : NR_DIRTIED, /* page dirtyings since bootup */
200 : NR_WRITTEN, /* page writings since bootup */
201 : NR_KERNEL_MISC_RECLAIMABLE, /* reclaimable non-slab kernel pages */
202 : NR_FOLL_PIN_ACQUIRED, /* via: pin_user_page(), gup flag: FOLL_PIN */
203 : NR_FOLL_PIN_RELEASED, /* pages returned via unpin_user_page() */
204 : NR_KERNEL_STACK_KB, /* measured in KiB */
205 : #if IS_ENABLED(CONFIG_SHADOW_CALL_STACK)
206 : NR_KERNEL_SCS_KB, /* measured in KiB */
207 : #endif
208 : NR_PAGETABLE, /* used for pagetables */
209 : #ifdef CONFIG_SWAP
210 : NR_SWAPCACHE,
211 : #endif
212 : NR_VM_NODE_STAT_ITEMS
213 : };
214 :
215 : /*
216 : * Returns true if the item should be printed in THPs (/proc/vmstat
217 : * currently prints number of anon, file and shmem THPs. But the item
218 : * is charged in pages).
219 : */
220 0 : static __always_inline bool vmstat_item_print_in_thp(enum node_stat_item item)
221 : {
222 0 : if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE))
223 : return false;
224 :
225 0 : return item == NR_ANON_THPS ||
226 0 : item == NR_FILE_THPS ||
227 0 : item == NR_SHMEM_THPS ||
228 0 : item == NR_SHMEM_PMDMAPPED ||
229 : item == NR_FILE_PMDMAPPED;
230 : }
231 :
232 : /*
233 : * Returns true if the value is measured in bytes (most vmstat values are
234 : * measured in pages). This defines the API part, the internal representation
235 : * might be different.
236 : */
237 678107 : static __always_inline bool vmstat_item_in_bytes(int idx)
238 : {
239 : /*
240 : * Global and per-node slab counters track slab pages.
241 : * It's expected that changes are multiples of PAGE_SIZE.
242 : * Internally values are stored in pages.
243 : *
244 : * Per-memcg and per-lruvec counters track memory, consumed
245 : * by individual slab objects. These counters are actually
246 : * byte-precise.
247 : */
248 678107 : return (idx == NR_SLAB_RECLAIMABLE_B ||
249 : idx == NR_SLAB_UNRECLAIMABLE_B);
250 : }
251 :
252 : /*
253 : * We do arithmetic on the LRU lists in various places in the code,
254 : * so it is important to keep the active lists LRU_ACTIVE higher in
255 : * the array than the corresponding inactive lists, and to keep
256 : * the *_FILE lists LRU_FILE higher than the corresponding _ANON lists.
257 : *
258 : * This has to be kept in sync with the statistics in zone_stat_item
259 : * above and the descriptions in vmstat_text in mm/vmstat.c
260 : */
261 : #define LRU_BASE 0
262 : #define LRU_ACTIVE 1
263 : #define LRU_FILE 2
264 :
265 : enum lru_list {
266 : LRU_INACTIVE_ANON = LRU_BASE,
267 : LRU_ACTIVE_ANON = LRU_BASE + LRU_ACTIVE,
268 : LRU_INACTIVE_FILE = LRU_BASE + LRU_FILE,
269 : LRU_ACTIVE_FILE = LRU_BASE + LRU_FILE + LRU_ACTIVE,
270 : LRU_UNEVICTABLE,
271 : NR_LRU_LISTS
272 : };
273 :
274 : #define for_each_lru(lru) for (lru = 0; lru < NR_LRU_LISTS; lru++)
275 :
276 : #define for_each_evictable_lru(lru) for (lru = 0; lru <= LRU_ACTIVE_FILE; lru++)
277 :
278 0 : static inline bool is_file_lru(enum lru_list lru)
279 : {
280 0 : return (lru == LRU_INACTIVE_FILE || lru == LRU_ACTIVE_FILE);
281 : }
282 :
283 0 : static inline bool is_active_lru(enum lru_list lru)
284 : {
285 0 : return (lru == LRU_ACTIVE_ANON || lru == LRU_ACTIVE_FILE);
286 : }
287 :
288 : #define ANON_AND_FILE 2
289 :
290 : enum lruvec_flags {
291 : LRUVEC_CONGESTED, /* lruvec has many dirty pages
292 : * backed by a congested BDI
293 : */
294 : };
295 :
296 : struct lruvec {
297 : struct list_head lists[NR_LRU_LISTS];
298 : /* per lruvec lru_lock for memcg */
299 : spinlock_t lru_lock;
300 : /*
301 : * These track the cost of reclaiming one LRU - file or anon -
302 : * over the other. As the observed cost of reclaiming one LRU
303 : * increases, the reclaim scan balance tips toward the other.
304 : */
305 : unsigned long anon_cost;
306 : unsigned long file_cost;
307 : /* Non-resident age, driven by LRU movement */
308 : atomic_long_t nonresident_age;
309 : /* Refaults at the time of last reclaim cycle */
310 : unsigned long refaults[ANON_AND_FILE];
311 : /* Various lruvec state flags (enum lruvec_flags) */
312 : unsigned long flags;
313 : #ifdef CONFIG_MEMCG
314 : struct pglist_data *pgdat;
315 : #endif
316 : };
317 :
318 : /* Isolate unmapped pages */
319 : #define ISOLATE_UNMAPPED ((__force isolate_mode_t)0x2)
320 : /* Isolate for asynchronous migration */
321 : #define ISOLATE_ASYNC_MIGRATE ((__force isolate_mode_t)0x4)
322 : /* Isolate unevictable pages */
323 : #define ISOLATE_UNEVICTABLE ((__force isolate_mode_t)0x8)
324 :
325 : /* LRU Isolation modes. */
326 : typedef unsigned __bitwise isolate_mode_t;
327 :
328 : enum zone_watermarks {
329 : WMARK_MIN,
330 : WMARK_LOW,
331 : WMARK_HIGH,
332 : NR_WMARK
333 : };
334 :
335 : #define min_wmark_pages(z) (z->_watermark[WMARK_MIN] + z->watermark_boost)
336 : #define low_wmark_pages(z) (z->_watermark[WMARK_LOW] + z->watermark_boost)
337 : #define high_wmark_pages(z) (z->_watermark[WMARK_HIGH] + z->watermark_boost)
338 : #define wmark_pages(z, i) (z->_watermark[i] + z->watermark_boost)
339 :
340 : struct per_cpu_pages {
341 : int count; /* number of pages in the list */
342 : int high; /* high watermark, emptying needed */
343 : int batch; /* chunk size for buddy add/remove */
344 :
345 : /* Lists of pages, one per migrate type stored on the pcp-lists */
346 : struct list_head lists[MIGRATE_PCPTYPES];
347 : };
348 :
349 : struct per_cpu_pageset {
350 : struct per_cpu_pages pcp;
351 : #ifdef CONFIG_NUMA
352 : s8 expire;
353 : u16 vm_numa_stat_diff[NR_VM_NUMA_STAT_ITEMS];
354 : #endif
355 : #ifdef CONFIG_SMP
356 : s8 stat_threshold;
357 : s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS];
358 : #endif
359 : };
360 :
361 : struct per_cpu_nodestat {
362 : s8 stat_threshold;
363 : s8 vm_node_stat_diff[NR_VM_NODE_STAT_ITEMS];
364 : };
365 :
366 : #endif /* !__GENERATING_BOUNDS.H */
367 :
368 : enum zone_type {
369 : /*
370 : * ZONE_DMA and ZONE_DMA32 are used when there are peripherals not able
371 : * to DMA to all of the addressable memory (ZONE_NORMAL).
372 : * On architectures where this area covers the whole 32 bit address
373 : * space ZONE_DMA32 is used. ZONE_DMA is left for the ones with smaller
374 : * DMA addressing constraints. This distinction is important as a 32bit
375 : * DMA mask is assumed when ZONE_DMA32 is defined. Some 64-bit
376 : * platforms may need both zones as they support peripherals with
377 : * different DMA addressing limitations.
378 : */
379 : #ifdef CONFIG_ZONE_DMA
380 : ZONE_DMA,
381 : #endif
382 : #ifdef CONFIG_ZONE_DMA32
383 : ZONE_DMA32,
384 : #endif
385 : /*
386 : * Normal addressable memory is in ZONE_NORMAL. DMA operations can be
387 : * performed on pages in ZONE_NORMAL if the DMA devices support
388 : * transfers to all addressable memory.
389 : */
390 : ZONE_NORMAL,
391 : #ifdef CONFIG_HIGHMEM
392 : /*
393 : * A memory area that is only addressable by the kernel through
394 : * mapping portions into its own address space. This is for example
395 : * used by i386 to allow the kernel to address the memory beyond
396 : * 900MB. The kernel will set up special mappings (page
397 : * table entries on i386) for each page that the kernel needs to
398 : * access.
399 : */
400 : ZONE_HIGHMEM,
401 : #endif
402 : /*
403 : * ZONE_MOVABLE is similar to ZONE_NORMAL, except that it contains
404 : * movable pages with few exceptional cases described below. Main use
405 : * cases for ZONE_MOVABLE are to make memory offlining/unplug more
406 : * likely to succeed, and to locally limit unmovable allocations - e.g.,
407 : * to increase the number of THP/huge pages. Notable special cases are:
408 : *
409 : * 1. Pinned pages: (long-term) pinning of movable pages might
410 : * essentially turn such pages unmovable. Memory offlining might
411 : * retry a long time.
412 : * 2. memblock allocations: kernelcore/movablecore setups might create
413 : * situations where ZONE_MOVABLE contains unmovable allocations
414 : * after boot. Memory offlining and allocations fail early.
415 : * 3. Memory holes: kernelcore/movablecore setups might create very rare
416 : * situations where ZONE_MOVABLE contains memory holes after boot,
417 : * for example, if we have sections that are only partially
418 : * populated. Memory offlining and allocations fail early.
419 : * 4. PG_hwpoison pages: while poisoned pages can be skipped during
420 : * memory offlining, such pages cannot be allocated.
421 : * 5. Unmovable PG_offline pages: in paravirtualized environments,
422 : * hotplugged memory blocks might only partially be managed by the
423 : * buddy (e.g., via XEN-balloon, Hyper-V balloon, virtio-mem). The
424 : * parts not manged by the buddy are unmovable PG_offline pages. In
425 : * some cases (virtio-mem), such pages can be skipped during
426 : * memory offlining, however, cannot be moved/allocated. These
427 : * techniques might use alloc_contig_range() to hide previously
428 : * exposed pages from the buddy again (e.g., to implement some sort
429 : * of memory unplug in virtio-mem).
430 : *
431 : * In general, no unmovable allocations that degrade memory offlining
432 : * should end up in ZONE_MOVABLE. Allocators (like alloc_contig_range())
433 : * have to expect that migrating pages in ZONE_MOVABLE can fail (even
434 : * if has_unmovable_pages() states that there are no unmovable pages,
435 : * there can be false negatives).
436 : */
437 : ZONE_MOVABLE,
438 : #ifdef CONFIG_ZONE_DEVICE
439 : ZONE_DEVICE,
440 : #endif
441 : __MAX_NR_ZONES
442 :
443 : };
444 :
445 : #ifndef __GENERATING_BOUNDS_H
446 :
447 : #define ASYNC_AND_SYNC 2
448 :
449 : struct zone {
450 : /* Read-mostly fields */
451 :
452 : /* zone watermarks, access with *_wmark_pages(zone) macros */
453 : unsigned long _watermark[NR_WMARK];
454 : unsigned long watermark_boost;
455 :
456 : unsigned long nr_reserved_highatomic;
457 :
458 : /*
459 : * We don't know if the memory that we're going to allocate will be
460 : * freeable or/and it will be released eventually, so to avoid totally
461 : * wasting several GB of ram we must reserve some of the lower zone
462 : * memory (otherwise we risk to run OOM on the lower zones despite
463 : * there being tons of freeable ram on the higher zones). This array is
464 : * recalculated at runtime if the sysctl_lowmem_reserve_ratio sysctl
465 : * changes.
466 : */
467 : long lowmem_reserve[MAX_NR_ZONES];
468 :
469 : #ifdef CONFIG_NUMA
470 : int node;
471 : #endif
472 : struct pglist_data *zone_pgdat;
473 : struct per_cpu_pageset __percpu *pageset;
474 : /*
475 : * the high and batch values are copied to individual pagesets for
476 : * faster access
477 : */
478 : int pageset_high;
479 : int pageset_batch;
480 :
481 : #ifndef CONFIG_SPARSEMEM
482 : /*
483 : * Flags for a pageblock_nr_pages block. See pageblock-flags.h.
484 : * In SPARSEMEM, this map is stored in struct mem_section
485 : */
486 : unsigned long *pageblock_flags;
487 : #endif /* CONFIG_SPARSEMEM */
488 :
489 : /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
490 : unsigned long zone_start_pfn;
491 :
492 : /*
493 : * spanned_pages is the total pages spanned by the zone, including
494 : * holes, which is calculated as:
495 : * spanned_pages = zone_end_pfn - zone_start_pfn;
496 : *
497 : * present_pages is physical pages existing within the zone, which
498 : * is calculated as:
499 : * present_pages = spanned_pages - absent_pages(pages in holes);
500 : *
501 : * managed_pages is present pages managed by the buddy system, which
502 : * is calculated as (reserved_pages includes pages allocated by the
503 : * bootmem allocator):
504 : * managed_pages = present_pages - reserved_pages;
505 : *
506 : * cma pages is present pages that are assigned for CMA use
507 : * (MIGRATE_CMA).
508 : *
509 : * So present_pages may be used by memory hotplug or memory power
510 : * management logic to figure out unmanaged pages by checking
511 : * (present_pages - managed_pages). And managed_pages should be used
512 : * by page allocator and vm scanner to calculate all kinds of watermarks
513 : * and thresholds.
514 : *
515 : * Locking rules:
516 : *
517 : * zone_start_pfn and spanned_pages are protected by span_seqlock.
518 : * It is a seqlock because it has to be read outside of zone->lock,
519 : * and it is done in the main allocator path. But, it is written
520 : * quite infrequently.
521 : *
522 : * The span_seq lock is declared along with zone->lock because it is
523 : * frequently read in proximity to zone->lock. It's good to
524 : * give them a chance of being in the same cacheline.
525 : *
526 : * Write access to present_pages at runtime should be protected by
527 : * mem_hotplug_begin/end(). Any reader who can't tolerant drift of
528 : * present_pages should get_online_mems() to get a stable value.
529 : */
530 : atomic_long_t managed_pages;
531 : unsigned long spanned_pages;
532 : unsigned long present_pages;
533 : #ifdef CONFIG_CMA
534 : unsigned long cma_pages;
535 : #endif
536 :
537 : const char *name;
538 :
539 : #ifdef CONFIG_MEMORY_ISOLATION
540 : /*
541 : * Number of isolated pageblock. It is used to solve incorrect
542 : * freepage counting problem due to racy retrieving migratetype
543 : * of pageblock. Protected by zone->lock.
544 : */
545 : unsigned long nr_isolate_pageblock;
546 : #endif
547 :
548 : #ifdef CONFIG_MEMORY_HOTPLUG
549 : /* see spanned/present_pages for more description */
550 : seqlock_t span_seqlock;
551 : #endif
552 :
553 : int initialized;
554 :
555 : /* Write-intensive fields used from the page allocator */
556 : ZONE_PADDING(_pad1_)
557 :
558 : /* free areas of different sizes */
559 : struct free_area free_area[MAX_ORDER];
560 :
561 : /* zone flags, see below */
562 : unsigned long flags;
563 :
564 : /* Primarily protects free_area */
565 : spinlock_t lock;
566 :
567 : /* Write-intensive fields used by compaction and vmstats. */
568 : ZONE_PADDING(_pad2_)
569 :
570 : /*
571 : * When free pages are below this point, additional steps are taken
572 : * when reading the number of free pages to avoid per-cpu counter
573 : * drift allowing watermarks to be breached
574 : */
575 : unsigned long percpu_drift_mark;
576 :
577 : #if defined CONFIG_COMPACTION || defined CONFIG_CMA
578 : /* pfn where compaction free scanner should start */
579 : unsigned long compact_cached_free_pfn;
580 : /* pfn where compaction migration scanner should start */
581 : unsigned long compact_cached_migrate_pfn[ASYNC_AND_SYNC];
582 : unsigned long compact_init_migrate_pfn;
583 : unsigned long compact_init_free_pfn;
584 : #endif
585 :
586 : #ifdef CONFIG_COMPACTION
587 : /*
588 : * On compaction failure, 1<<compact_defer_shift compactions
589 : * are skipped before trying again. The number attempted since
590 : * last failure is tracked with compact_considered.
591 : * compact_order_failed is the minimum compaction failed order.
592 : */
593 : unsigned int compact_considered;
594 : unsigned int compact_defer_shift;
595 : int compact_order_failed;
596 : #endif
597 :
598 : #if defined CONFIG_COMPACTION || defined CONFIG_CMA
599 : /* Set to true when the PG_migrate_skip bits should be cleared */
600 : bool compact_blockskip_flush;
601 : #endif
602 :
603 : bool contiguous;
604 :
605 : ZONE_PADDING(_pad3_)
606 : /* Zone statistics */
607 : atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
608 : atomic_long_t vm_numa_stat[NR_VM_NUMA_STAT_ITEMS];
609 : } ____cacheline_internodealigned_in_smp;
610 :
611 : enum pgdat_flags {
612 : PGDAT_DIRTY, /* reclaim scanning has recently found
613 : * many dirty file pages at the tail
614 : * of the LRU.
615 : */
616 : PGDAT_WRITEBACK, /* reclaim scanning has recently found
617 : * many pages under writeback
618 : */
619 : PGDAT_RECLAIM_LOCKED, /* prevents concurrent reclaim */
620 : };
621 :
622 : enum zone_flags {
623 : ZONE_BOOSTED_WATERMARK, /* zone recently boosted watermarks.
624 : * Cleared when kswapd is woken.
625 : */
626 : };
627 :
628 13 : static inline unsigned long zone_managed_pages(struct zone *zone)
629 : {
630 49 : return (unsigned long)atomic_long_read(&zone->managed_pages);
631 : }
632 :
633 0 : static inline unsigned long zone_cma_pages(struct zone *zone)
634 : {
635 : #ifdef CONFIG_CMA
636 : return zone->cma_pages;
637 : #else
638 0 : return 0;
639 : #endif
640 : }
641 :
642 291468 : static inline unsigned long zone_end_pfn(const struct zone *zone)
643 : {
644 257 : return zone->zone_start_pfn + zone->spanned_pages;
645 : }
646 :
647 290947 : static inline bool zone_spans_pfn(const struct zone *zone, unsigned long pfn)
648 : {
649 290947 : return zone->zone_start_pfn <= pfn && pfn < zone_end_pfn(zone);
650 : }
651 :
652 37450 : static inline bool zone_is_initialized(struct zone *zone)
653 : {
654 37450 : return zone->initialized;
655 : }
656 :
657 : static inline bool zone_is_empty(struct zone *zone)
658 : {
659 : return zone->spanned_pages == 0;
660 : }
661 :
662 : /*
663 : * Return true if [start_pfn, start_pfn + nr_pages) range has a non-empty
664 : * intersection with the given zone
665 : */
666 : static inline bool zone_intersects(struct zone *zone,
667 : unsigned long start_pfn, unsigned long nr_pages)
668 : {
669 : if (zone_is_empty(zone))
670 : return false;
671 : if (start_pfn >= zone_end_pfn(zone) ||
672 : start_pfn + nr_pages <= zone->zone_start_pfn)
673 : return false;
674 :
675 : return true;
676 : }
677 :
678 : /*
679 : * The "priority" of VM scanning is how much of the queues we will scan in one
680 : * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
681 : * queues ("queue_length >> 12") during an aging round.
682 : */
683 : #define DEF_PRIORITY 12
684 :
685 : /* Maximum number of zones on a zonelist */
686 : #define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
687 :
688 : enum {
689 : ZONELIST_FALLBACK, /* zonelist with fallback */
690 : #ifdef CONFIG_NUMA
691 : /*
692 : * The NUMA zonelists are doubled because we need zonelists that
693 : * restrict the allocations to a single node for __GFP_THISNODE.
694 : */
695 : ZONELIST_NOFALLBACK, /* zonelist without fallback (__GFP_THISNODE) */
696 : #endif
697 : MAX_ZONELISTS
698 : };
699 :
700 : /*
701 : * This struct contains information about a zone in a zonelist. It is stored
702 : * here to avoid dereferences into large structures and lookups of tables
703 : */
704 : struct zoneref {
705 : struct zone *zone; /* Pointer to actual zone */
706 : int zone_idx; /* zone_idx(zoneref->zone) */
707 : };
708 :
709 : /*
710 : * One allocation request operates on a zonelist. A zonelist
711 : * is a list of zones, the first one is the 'goal' of the
712 : * allocation, the other zones are fallback zones, in decreasing
713 : * priority.
714 : *
715 : * To speed the reading of the zonelist, the zonerefs contain the zone index
716 : * of the entry being read. Helper functions to access information given
717 : * a struct zoneref are
718 : *
719 : * zonelist_zone() - Return the struct zone * for an entry in _zonerefs
720 : * zonelist_zone_idx() - Return the index of the zone for an entry
721 : * zonelist_node_idx() - Return the index of the node for an entry
722 : */
723 : struct zonelist {
724 : struct zoneref _zonerefs[MAX_ZONES_PER_ZONELIST + 1];
725 : };
726 :
727 : #ifndef CONFIG_DISCONTIGMEM
728 : /* The array of struct pages - for discontigmem use pgdat->lmem_map */
729 : extern struct page *mem_map;
730 : #endif
731 :
732 : #ifdef CONFIG_TRANSPARENT_HUGEPAGE
733 : struct deferred_split {
734 : spinlock_t split_queue_lock;
735 : struct list_head split_queue;
736 : unsigned long split_queue_len;
737 : };
738 : #endif
739 :
740 : /*
741 : * On NUMA machines, each NUMA node would have a pg_data_t to describe
742 : * it's memory layout. On UMA machines there is a single pglist_data which
743 : * describes the whole memory.
744 : *
745 : * Memory statistics and page replacement data structures are maintained on a
746 : * per-zone basis.
747 : */
748 : typedef struct pglist_data {
749 : /*
750 : * node_zones contains just the zones for THIS node. Not all of the
751 : * zones may be populated, but it is the full list. It is referenced by
752 : * this node's node_zonelists as well as other node's node_zonelists.
753 : */
754 : struct zone node_zones[MAX_NR_ZONES];
755 :
756 : /*
757 : * node_zonelists contains references to all zones in all nodes.
758 : * Generally the first zones will be references to this node's
759 : * node_zones.
760 : */
761 : struct zonelist node_zonelists[MAX_ZONELISTS];
762 :
763 : int nr_zones; /* number of populated zones in this node */
764 : #ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */
765 : struct page *node_mem_map;
766 : #ifdef CONFIG_PAGE_EXTENSION
767 : struct page_ext *node_page_ext;
768 : #endif
769 : #endif
770 : #if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT)
771 : /*
772 : * Must be held any time you expect node_start_pfn,
773 : * node_present_pages, node_spanned_pages or nr_zones to stay constant.
774 : * Also synchronizes pgdat->first_deferred_pfn during deferred page
775 : * init.
776 : *
777 : * pgdat_resize_lock() and pgdat_resize_unlock() are provided to
778 : * manipulate node_size_lock without checking for CONFIG_MEMORY_HOTPLUG
779 : * or CONFIG_DEFERRED_STRUCT_PAGE_INIT.
780 : *
781 : * Nests above zone->lock and zone->span_seqlock
782 : */
783 : spinlock_t node_size_lock;
784 : #endif
785 : unsigned long node_start_pfn;
786 : unsigned long node_present_pages; /* total number of physical pages */
787 : unsigned long node_spanned_pages; /* total size of physical page
788 : range, including holes */
789 : int node_id;
790 : wait_queue_head_t kswapd_wait;
791 : wait_queue_head_t pfmemalloc_wait;
792 : struct task_struct *kswapd; /* Protected by
793 : mem_hotplug_begin/end() */
794 : int kswapd_order;
795 : enum zone_type kswapd_highest_zoneidx;
796 :
797 : int kswapd_failures; /* Number of 'reclaimed == 0' runs */
798 :
799 : #ifdef CONFIG_COMPACTION
800 : int kcompactd_max_order;
801 : enum zone_type kcompactd_highest_zoneidx;
802 : wait_queue_head_t kcompactd_wait;
803 : struct task_struct *kcompactd;
804 : #endif
805 : /*
806 : * This is a per-node reserve of pages that are not available
807 : * to userspace allocations.
808 : */
809 : unsigned long totalreserve_pages;
810 :
811 : #ifdef CONFIG_NUMA
812 : /*
813 : * node reclaim becomes active if more unmapped pages exist.
814 : */
815 : unsigned long min_unmapped_pages;
816 : unsigned long min_slab_pages;
817 : #endif /* CONFIG_NUMA */
818 :
819 : /* Write-intensive fields used by page reclaim */
820 : ZONE_PADDING(_pad1_)
821 :
822 : #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
823 : /*
824 : * If memory initialisation on large machines is deferred then this
825 : * is the first PFN that needs to be initialised.
826 : */
827 : unsigned long first_deferred_pfn;
828 : #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
829 :
830 : #ifdef CONFIG_TRANSPARENT_HUGEPAGE
831 : struct deferred_split deferred_split_queue;
832 : #endif
833 :
834 : /* Fields commonly accessed by the page reclaim scanner */
835 :
836 : /*
837 : * NOTE: THIS IS UNUSED IF MEMCG IS ENABLED.
838 : *
839 : * Use mem_cgroup_lruvec() to look up lruvecs.
840 : */
841 : struct lruvec __lruvec;
842 :
843 : unsigned long flags;
844 :
845 : ZONE_PADDING(_pad2_)
846 :
847 : /* Per-node vmstats */
848 : struct per_cpu_nodestat __percpu *per_cpu_nodestats;
849 : atomic_long_t vm_stat[NR_VM_NODE_STAT_ITEMS];
850 : } pg_data_t;
851 :
852 : #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
853 : #define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)
854 : #ifdef CONFIG_FLAT_NODE_MEM_MAP
855 : #define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr))
856 : #else
857 : #define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr))
858 : #endif
859 : #define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr))
860 :
861 : #define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)
862 : #define node_end_pfn(nid) pgdat_end_pfn(NODE_DATA(nid))
863 :
864 0 : static inline unsigned long pgdat_end_pfn(pg_data_t *pgdat)
865 : {
866 0 : return pgdat->node_start_pfn + pgdat->node_spanned_pages;
867 : }
868 :
869 : static inline bool pgdat_is_empty(pg_data_t *pgdat)
870 : {
871 : return !pgdat->node_start_pfn && !pgdat->node_spanned_pages;
872 : }
873 :
874 : #include <linux/memory_hotplug.h>
875 :
876 : void build_all_zonelists(pg_data_t *pgdat);
877 : void wakeup_kswapd(struct zone *zone, gfp_t gfp_mask, int order,
878 : enum zone_type highest_zoneidx);
879 : bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
880 : int highest_zoneidx, unsigned int alloc_flags,
881 : long free_pages);
882 : bool zone_watermark_ok(struct zone *z, unsigned int order,
883 : unsigned long mark, int highest_zoneidx,
884 : unsigned int alloc_flags);
885 : bool zone_watermark_ok_safe(struct zone *z, unsigned int order,
886 : unsigned long mark, int highest_zoneidx);
887 : /*
888 : * Memory initialization context, use to differentiate memory added by
889 : * the platform statically or via memory hotplug interface.
890 : */
891 : enum meminit_context {
892 : MEMINIT_EARLY,
893 : MEMINIT_HOTPLUG,
894 : };
895 :
896 : extern void init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,
897 : unsigned long size);
898 :
899 : extern void lruvec_init(struct lruvec *lruvec);
900 :
901 196996 : static inline struct pglist_data *lruvec_pgdat(struct lruvec *lruvec)
902 : {
903 : #ifdef CONFIG_MEMCG
904 : return lruvec->pgdat;
905 : #else
906 196996 : return container_of(lruvec, struct pglist_data, __lruvec);
907 : #endif
908 : }
909 :
910 : #ifdef CONFIG_HAVE_MEMORYLESS_NODES
911 : int local_memory_node(int node_id);
912 : #else
913 : static inline int local_memory_node(int node_id) { return node_id; };
914 : #endif
915 :
916 : /*
917 : * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
918 : */
919 : #define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
920 :
921 : #ifdef CONFIG_ZONE_DEVICE
922 : static inline bool zone_is_zone_device(struct zone *zone)
923 : {
924 : return zone_idx(zone) == ZONE_DEVICE;
925 : }
926 : #else
927 : static inline bool zone_is_zone_device(struct zone *zone)
928 : {
929 : return false;
930 : }
931 : #endif
932 :
933 : /*
934 : * Returns true if a zone has pages managed by the buddy allocator.
935 : * All the reclaim decisions have to use this function rather than
936 : * populated_zone(). If the whole zone is reserved then we can easily
937 : * end up with populated_zone() && !managed_zone().
938 : */
939 8 : static inline bool managed_zone(struct zone *zone)
940 : {
941 8 : return zone_managed_pages(zone);
942 : }
943 :
944 : /* Returns true if a zone has memory */
945 8207 : static inline bool populated_zone(struct zone *zone)
946 : {
947 8207 : return zone->present_pages;
948 : }
949 :
950 : #ifdef CONFIG_NUMA
951 413673 : static inline int zone_to_nid(struct zone *zone)
952 : {
953 220669 : return zone->node;
954 : }
955 :
956 3 : static inline void zone_set_nid(struct zone *zone, int nid)
957 : {
958 3 : zone->node = nid;
959 : }
960 : #else
961 : static inline int zone_to_nid(struct zone *zone)
962 : {
963 : return 0;
964 : }
965 :
966 : static inline void zone_set_nid(struct zone *zone, int nid) {}
967 : #endif
968 :
969 : extern int movable_zone;
970 :
971 : #ifdef CONFIG_HIGHMEM
972 : static inline int zone_movable_is_highmem(void)
973 : {
974 : #ifdef CONFIG_NEED_MULTIPLE_NODES
975 : return movable_zone == ZONE_HIGHMEM;
976 : #else
977 : return (ZONE_MOVABLE - 1) == ZONE_HIGHMEM;
978 : #endif
979 : }
980 : #endif
981 :
982 6 : static inline int is_highmem_idx(enum zone_type idx)
983 : {
984 : #ifdef CONFIG_HIGHMEM
985 : return (idx == ZONE_HIGHMEM ||
986 : (idx == ZONE_MOVABLE && zone_movable_is_highmem()));
987 : #else
988 6 : return 0;
989 : #endif
990 : }
991 :
992 : /**
993 : * is_highmem - helper function to quickly check if a struct zone is a
994 : * highmem zone or not. This is an attempt to keep references
995 : * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
996 : * @zone - pointer to struct zone variable
997 : */
998 12 : static inline int is_highmem(struct zone *zone)
999 : {
1000 : #ifdef CONFIG_HIGHMEM
1001 : return is_highmem_idx(zone_idx(zone));
1002 : #else
1003 12 : return 0;
1004 : #endif
1005 : }
1006 :
1007 : /* These two functions are used to setup the per zone pages min values */
1008 : struct ctl_table;
1009 :
1010 : int min_free_kbytes_sysctl_handler(struct ctl_table *, int, void *, size_t *,
1011 : loff_t *);
1012 : int watermark_scale_factor_sysctl_handler(struct ctl_table *, int, void *,
1013 : size_t *, loff_t *);
1014 : extern int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES];
1015 : int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *, int, void *,
1016 : size_t *, loff_t *);
1017 : int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *, int,
1018 : void *, size_t *, loff_t *);
1019 : int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *, int,
1020 : void *, size_t *, loff_t *);
1021 : int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *, int,
1022 : void *, size_t *, loff_t *);
1023 : int numa_zonelist_order_handler(struct ctl_table *, int,
1024 : void *, size_t *, loff_t *);
1025 : extern int percpu_pagelist_fraction;
1026 : extern char numa_zonelist_order[];
1027 : #define NUMA_ZONELIST_ORDER_LEN 16
1028 :
1029 : #ifndef CONFIG_NEED_MULTIPLE_NODES
1030 :
1031 : extern struct pglist_data contig_page_data;
1032 : #define NODE_DATA(nid) (&contig_page_data)
1033 : #define NODE_MEM_MAP(nid) mem_map
1034 :
1035 : #else /* CONFIG_NEED_MULTIPLE_NODES */
1036 :
1037 : #include <asm/mmzone.h>
1038 :
1039 : #endif /* !CONFIG_NEED_MULTIPLE_NODES */
1040 :
1041 : extern struct pglist_data *first_online_pgdat(void);
1042 : extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat);
1043 : extern struct zone *next_zone(struct zone *zone);
1044 :
1045 : /**
1046 : * for_each_online_pgdat - helper macro to iterate over all online nodes
1047 : * @pgdat - pointer to a pg_data_t variable
1048 : */
1049 : #define for_each_online_pgdat(pgdat) \
1050 : for (pgdat = first_online_pgdat(); \
1051 : pgdat; \
1052 : pgdat = next_online_pgdat(pgdat))
1053 : /**
1054 : * for_each_zone - helper macro to iterate over all memory zones
1055 : * @zone - pointer to struct zone variable
1056 : *
1057 : * The user only needs to declare the zone variable, for_each_zone
1058 : * fills it in.
1059 : */
1060 : #define for_each_zone(zone) \
1061 : for (zone = (first_online_pgdat())->node_zones; \
1062 : zone; \
1063 : zone = next_zone(zone))
1064 :
1065 : #define for_each_populated_zone(zone) \
1066 : for (zone = (first_online_pgdat())->node_zones; \
1067 : zone; \
1068 : zone = next_zone(zone)) \
1069 : if (!populated_zone(zone)) \
1070 : ; /* do nothing */ \
1071 : else
1072 :
1073 55031 : static inline struct zone *zonelist_zone(struct zoneref *zoneref)
1074 : {
1075 55031 : return zoneref->zone;
1076 : }
1077 :
1078 248160 : static inline int zonelist_zone_idx(struct zoneref *zoneref)
1079 : {
1080 248160 : return zoneref->zone_idx;
1081 : }
1082 :
1083 0 : static inline int zonelist_node_idx(struct zoneref *zoneref)
1084 : {
1085 0 : return zone_to_nid(zoneref->zone);
1086 : }
1087 :
1088 : struct zoneref *__next_zones_zonelist(struct zoneref *z,
1089 : enum zone_type highest_zoneidx,
1090 : nodemask_t *nodes);
1091 :
1092 : /**
1093 : * next_zones_zonelist - Returns the next zone at or below highest_zoneidx within the allowed nodemask using a cursor within a zonelist as a starting point
1094 : * @z - The cursor used as a starting point for the search
1095 : * @highest_zoneidx - The zone index of the highest zone to return
1096 : * @nodes - An optional nodemask to filter the zonelist with
1097 : *
1098 : * This function returns the next zone at or below a given zone index that is
1099 : * within the allowed nodemask using a cursor as the starting point for the
1100 : * search. The zoneref returned is a cursor that represents the current zone
1101 : * being examined. It should be advanced by one before calling
1102 : * next_zones_zonelist again.
1103 : */
1104 248160 : static __always_inline struct zoneref *next_zones_zonelist(struct zoneref *z,
1105 : enum zone_type highest_zoneidx,
1106 : nodemask_t *nodes)
1107 : {
1108 220642 : if (likely(!nodes && zonelist_zone_idx(z) <= highest_zoneidx))
1109 : return z;
1110 0 : return __next_zones_zonelist(z, highest_zoneidx, nodes);
1111 : }
1112 :
1113 : /**
1114 : * first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nodemask in a zonelist
1115 : * @zonelist - The zonelist to search for a suitable zone
1116 : * @highest_zoneidx - The zone index of the highest zone to return
1117 : * @nodes - An optional nodemask to filter the zonelist with
1118 : * @return - Zoneref pointer for the first suitable zone found (see below)
1119 : *
1120 : * This function returns the first zone at or below a given zone index that is
1121 : * within the allowed nodemask. The zoneref returned is a cursor that can be
1122 : * used to iterate the zonelist with next_zones_zonelist by advancing it by
1123 : * one before calling.
1124 : *
1125 : * When no eligible zone is found, zoneref->zone is NULL (zoneref itself is
1126 : * never NULL). This may happen either genuinely, or due to concurrent nodemask
1127 : * update due to cpuset modification.
1128 : */
1129 220647 : static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist,
1130 : enum zone_type highest_zoneidx,
1131 : nodemask_t *nodes)
1132 : {
1133 220647 : return next_zones_zonelist(zonelist->_zonerefs,
1134 : highest_zoneidx, nodes);
1135 : }
1136 :
1137 : /**
1138 : * for_each_zone_zonelist_nodemask - helper macro to iterate over valid zones in a zonelist at or below a given zone index and within a nodemask
1139 : * @zone - The current zone in the iterator
1140 : * @z - The current pointer within zonelist->_zonerefs being iterated
1141 : * @zlist - The zonelist being iterated
1142 : * @highidx - The zone index of the highest zone to return
1143 : * @nodemask - Nodemask allowed by the allocator
1144 : *
1145 : * This iterator iterates though all zones at or below a given zone index and
1146 : * within a given nodemask
1147 : */
1148 : #define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
1149 : for (z = first_zones_zonelist(zlist, highidx, nodemask), zone = zonelist_zone(z); \
1150 : zone; \
1151 : z = next_zones_zonelist(++z, highidx, nodemask), \
1152 : zone = zonelist_zone(z))
1153 :
1154 : #define for_next_zone_zonelist_nodemask(zone, z, highidx, nodemask) \
1155 : for (zone = z->zone; \
1156 : zone; \
1157 : z = next_zones_zonelist(++z, highidx, nodemask), \
1158 : zone = zonelist_zone(z))
1159 :
1160 :
1161 : /**
1162 : * for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index
1163 : * @zone - The current zone in the iterator
1164 : * @z - The current pointer within zonelist->zones being iterated
1165 : * @zlist - The zonelist being iterated
1166 : * @highidx - The zone index of the highest zone to return
1167 : *
1168 : * This iterator iterates though all zones at or below a given zone index.
1169 : */
1170 : #define for_each_zone_zonelist(zone, z, zlist, highidx) \
1171 : for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)
1172 :
1173 : #ifdef CONFIG_SPARSEMEM
1174 : #include <asm/sparsemem.h>
1175 : #endif
1176 :
1177 : #ifdef CONFIG_FLATMEM
1178 : #define pfn_to_nid(pfn) (0)
1179 : #endif
1180 :
1181 : #ifdef CONFIG_SPARSEMEM
1182 :
1183 : /*
1184 : * SECTION_SHIFT #bits space required to store a section #
1185 : *
1186 : * PA_SECTION_SHIFT physical address to/from section number
1187 : * PFN_SECTION_SHIFT pfn to/from section number
1188 : */
1189 : #define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
1190 : #define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)
1191 :
1192 : #define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
1193 :
1194 : #define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)
1195 : #define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))
1196 :
1197 : #define SECTION_BLOCKFLAGS_BITS \
1198 : ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS)
1199 :
1200 : #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
1201 : #error Allocator MAX_ORDER exceeds SECTION_SIZE
1202 : #endif
1203 :
1204 8199259 : static inline unsigned long pfn_to_section_nr(unsigned long pfn)
1205 : {
1206 8199259 : return pfn >> PFN_SECTION_SHIFT;
1207 : }
1208 16 : static inline unsigned long section_nr_to_pfn(unsigned long sec)
1209 : {
1210 16 : return sec << PFN_SECTION_SHIFT;
1211 : }
1212 :
1213 : #define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)
1214 : #define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)
1215 :
1216 : #define SUBSECTION_SHIFT 21
1217 : #define SUBSECTION_SIZE (1UL << SUBSECTION_SHIFT)
1218 :
1219 : #define PFN_SUBSECTION_SHIFT (SUBSECTION_SHIFT - PAGE_SHIFT)
1220 : #define PAGES_PER_SUBSECTION (1UL << PFN_SUBSECTION_SHIFT)
1221 : #define PAGE_SUBSECTION_MASK (~(PAGES_PER_SUBSECTION-1))
1222 :
1223 : #if SUBSECTION_SHIFT > SECTION_SIZE_BITS
1224 : #error Subsection size exceeds section size
1225 : #else
1226 : #define SUBSECTIONS_PER_SECTION (1UL << (SECTION_SIZE_BITS - SUBSECTION_SHIFT))
1227 : #endif
1228 :
1229 : #define SUBSECTION_ALIGN_UP(pfn) ALIGN((pfn), PAGES_PER_SUBSECTION)
1230 : #define SUBSECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SUBSECTION_MASK)
1231 :
1232 : struct mem_section_usage {
1233 : #ifdef CONFIG_SPARSEMEM_VMEMMAP
1234 : DECLARE_BITMAP(subsection_map, SUBSECTIONS_PER_SECTION);
1235 : #endif
1236 : /* See declaration of similar field in struct zone */
1237 : unsigned long pageblock_flags[0];
1238 : };
1239 :
1240 : void subsection_map_init(unsigned long pfn, unsigned long nr_pages);
1241 :
1242 : struct page;
1243 : struct page_ext;
1244 : struct mem_section {
1245 : /*
1246 : * This is, logically, a pointer to an array of struct
1247 : * pages. However, it is stored with some other magic.
1248 : * (see sparse.c::sparse_init_one_section())
1249 : *
1250 : * Additionally during early boot we encode node id of
1251 : * the location of the section here to guide allocation.
1252 : * (see sparse.c::memory_present())
1253 : *
1254 : * Making it a UL at least makes someone do a cast
1255 : * before using it wrong.
1256 : */
1257 : unsigned long section_mem_map;
1258 :
1259 : struct mem_section_usage *usage;
1260 : #ifdef CONFIG_PAGE_EXTENSION
1261 : /*
1262 : * If SPARSEMEM, pgdat doesn't have page_ext pointer. We use
1263 : * section. (see page_ext.h about this.)
1264 : */
1265 : struct page_ext *page_ext;
1266 : unsigned long pad;
1267 : #endif
1268 : /*
1269 : * WARNING: mem_section must be a power-of-2 in size for the
1270 : * calculation and use of SECTION_ROOT_MASK to make sense.
1271 : */
1272 : };
1273 :
1274 : #ifdef CONFIG_SPARSEMEM_EXTREME
1275 : #define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))
1276 : #else
1277 : #define SECTIONS_PER_ROOT 1
1278 : #endif
1279 :
1280 : #define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
1281 : #define NR_SECTION_ROOTS DIV_ROUND_UP(NR_MEM_SECTIONS, SECTIONS_PER_ROOT)
1282 : #define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)
1283 :
1284 : #ifdef CONFIG_SPARSEMEM_EXTREME
1285 : extern struct mem_section **mem_section;
1286 : #else
1287 : extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
1288 : #endif
1289 :
1290 148615 : static inline unsigned long *section_to_usemap(struct mem_section *ms)
1291 : {
1292 148615 : return ms->usage->pageblock_flags;
1293 : }
1294 :
1295 12283222 : static inline struct mem_section *__nr_to_section(unsigned long nr)
1296 : {
1297 : #ifdef CONFIG_SPARSEMEM_EXTREME
1298 12283222 : if (!mem_section)
1299 : return NULL;
1300 : #endif
1301 12283222 : if (!mem_section[SECTION_NR_TO_ROOT(nr)])
1302 : return NULL;
1303 12283222 : return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK];
1304 : }
1305 : extern unsigned long __section_nr(struct mem_section *ms);
1306 : extern size_t mem_section_usage_size(void);
1307 :
1308 : /*
1309 : * We use the lower bits of the mem_map pointer to store
1310 : * a little bit of information. The pointer is calculated
1311 : * as mem_map - section_nr_to_pfn(pnum). The result is
1312 : * aligned to the minimum alignment of the two values:
1313 : * 1. All mem_map arrays are page-aligned.
1314 : * 2. section_nr_to_pfn() always clears PFN_SECTION_SHIFT
1315 : * lowest bits. PFN_SECTION_SHIFT is arch-specific
1316 : * (equal SECTION_SIZE_BITS - PAGE_SHIFT), and the
1317 : * worst combination is powerpc with 256k pages,
1318 : * which results in PFN_SECTION_SHIFT equal 6.
1319 : * To sum it up, at least 6 bits are available.
1320 : */
1321 : #define SECTION_MARKED_PRESENT (1UL<<0)
1322 : #define SECTION_HAS_MEM_MAP (1UL<<1)
1323 : #define SECTION_IS_ONLINE (1UL<<2)
1324 : #define SECTION_IS_EARLY (1UL<<3)
1325 : #define SECTION_TAINT_ZONE_DEVICE (1UL<<4)
1326 : #define SECTION_MAP_LAST_BIT (1UL<<5)
1327 : #define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1))
1328 : #define SECTION_NID_SHIFT 3
1329 :
1330 12061171 : static inline struct page *__section_mem_map_addr(struct mem_section *section)
1331 : {
1332 12061171 : unsigned long map = section->section_mem_map;
1333 12061171 : map &= SECTION_MAP_MASK;
1334 5381811 : return (struct page *)map;
1335 : }
1336 :
1337 16 : static inline int present_section(struct mem_section *section)
1338 : {
1339 16 : return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));
1340 : }
1341 :
1342 16 : static inline int present_section_nr(unsigned long nr)
1343 : {
1344 16 : return present_section(__nr_to_section(nr));
1345 : }
1346 :
1347 98026 : static inline int valid_section(struct mem_section *section)
1348 : {
1349 98026 : return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));
1350 : }
1351 :
1352 98026 : static inline int early_section(struct mem_section *section)
1353 : {
1354 98026 : return (section && (section->section_mem_map & SECTION_IS_EARLY));
1355 : }
1356 :
1357 : static inline int valid_section_nr(unsigned long nr)
1358 : {
1359 : return valid_section(__nr_to_section(nr));
1360 : }
1361 :
1362 : static inline int online_section(struct mem_section *section)
1363 : {
1364 : return (section && (section->section_mem_map & SECTION_IS_ONLINE));
1365 : }
1366 :
1367 : static inline int online_device_section(struct mem_section *section)
1368 : {
1369 : unsigned long flags = SECTION_IS_ONLINE | SECTION_TAINT_ZONE_DEVICE;
1370 :
1371 : return section && ((section->section_mem_map & flags) == flags);
1372 : }
1373 :
1374 : static inline int online_section_nr(unsigned long nr)
1375 : {
1376 : return online_section(__nr_to_section(nr));
1377 : }
1378 :
1379 : #ifdef CONFIG_MEMORY_HOTPLUG
1380 : void online_mem_sections(unsigned long start_pfn, unsigned long end_pfn);
1381 : #ifdef CONFIG_MEMORY_HOTREMOVE
1382 : void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn);
1383 : #endif
1384 : #endif
1385 :
1386 7741054 : static inline struct mem_section *__pfn_to_section(unsigned long pfn)
1387 : {
1388 7381523 : return __nr_to_section(pfn_to_section_nr(pfn));
1389 : }
1390 :
1391 : extern unsigned long __highest_present_section_nr;
1392 :
1393 : static inline int subsection_map_index(unsigned long pfn)
1394 : {
1395 : return (pfn & ~(PAGE_SECTION_MASK)) / PAGES_PER_SUBSECTION;
1396 : }
1397 :
1398 : #ifdef CONFIG_SPARSEMEM_VMEMMAP
1399 : static inline int pfn_section_valid(struct mem_section *ms, unsigned long pfn)
1400 : {
1401 : int idx = subsection_map_index(pfn);
1402 :
1403 : return test_bit(idx, ms->usage->subsection_map);
1404 : }
1405 : #else
1406 : static inline int pfn_section_valid(struct mem_section *ms, unsigned long pfn)
1407 : {
1408 : return 1;
1409 : }
1410 : #endif
1411 :
1412 : #ifndef CONFIG_HAVE_ARCH_PFN_VALID
1413 98026 : static inline int pfn_valid(unsigned long pfn)
1414 : {
1415 98026 : struct mem_section *ms;
1416 :
1417 98026 : if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
1418 : return 0;
1419 98026 : ms = __nr_to_section(pfn_to_section_nr(pfn));
1420 98026 : if (!valid_section(ms))
1421 : return 0;
1422 : /*
1423 : * Traditionally early sections always returned pfn_valid() for
1424 : * the entire section-sized span.
1425 : */
1426 98026 : return early_section(ms) || pfn_section_valid(ms, pfn);
1427 : }
1428 : #endif
1429 :
1430 : static inline int pfn_in_present_section(unsigned long pfn)
1431 : {
1432 : if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
1433 : return 0;
1434 : return present_section(__nr_to_section(pfn_to_section_nr(pfn)));
1435 : }
1436 :
1437 18 : static inline unsigned long next_present_section_nr(unsigned long section_nr)
1438 : {
1439 18 : while (++section_nr <= __highest_present_section_nr) {
1440 16 : if (present_section_nr(section_nr))
1441 16 : return section_nr;
1442 : }
1443 :
1444 : return -1;
1445 : }
1446 :
1447 : /*
1448 : * These are _only_ used during initialisation, therefore they
1449 : * can use __initdata ... They could have names to indicate
1450 : * this restriction.
1451 : */
1452 : #ifdef CONFIG_NUMA
1453 : #define pfn_to_nid(pfn) \
1454 : ({ \
1455 : unsigned long __pfn_to_nid_pfn = (pfn); \
1456 : page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \
1457 : })
1458 : #else
1459 : #define pfn_to_nid(pfn) (0)
1460 : #endif
1461 :
1462 : void sparse_init(void);
1463 : #else
1464 : #define sparse_init() do {} while (0)
1465 : #define sparse_index_init(_sec, _nid) do {} while (0)
1466 : #define pfn_in_present_section pfn_valid
1467 : #define subsection_map_init(_pfn, _nr_pages) do {} while (0)
1468 : #endif /* CONFIG_SPARSEMEM */
1469 :
1470 : /*
1471 : * If it is possible to have holes within a MAX_ORDER_NR_PAGES, then we
1472 : * need to check pfn validity within that MAX_ORDER_NR_PAGES block.
1473 : * pfn_valid_within() should be used in this case; we optimise this away
1474 : * when we have no holes within a MAX_ORDER_NR_PAGES block.
1475 : */
1476 : #ifdef CONFIG_HOLES_IN_ZONE
1477 : #define pfn_valid_within(pfn) pfn_valid(pfn)
1478 : #else
1479 : #define pfn_valid_within(pfn) (1)
1480 : #endif
1481 :
1482 : #endif /* !__GENERATING_BOUNDS.H */
1483 : #endif /* !__ASSEMBLY__ */
1484 : #endif /* _LINUX_MMZONE_H */
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