1 #ifndef _LINUX_MMZONE_H
2 #define _LINUX_MMZONE_H
5 #ifndef __GENERATING_BOUNDS_H
7 #include <linux/spinlock.h>
8 #include <linux/list.h>
9 #include <linux/wait.h>
10 #include <linux/bitops.h>
11 #include <linux/cache.h>
12 #include <linux/threads.h>
13 #include <linux/numa.h>
14 #include <linux/init.h>
15 #include <linux/seqlock.h>
16 #include <linux/nodemask.h>
17 #include <linux/pageblock-flags.h>
18 #include <linux/page-flags-layout.h>
19 #include <linux/atomic.h>
22 /* Free memory management - zoned buddy allocator. */
23 #ifndef CONFIG_FORCE_MAX_ZONEORDER
26 #define MAX_ORDER CONFIG_FORCE_MAX_ZONEORDER
28 #define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1))
31 * PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed
32 * costly to service. That is between allocation orders which should
33 * coalesce naturally under reasonable reclaim pressure and those which
36 #define PAGE_ALLOC_COSTLY_ORDER 3
42 MIGRATE_PCPTYPES, /* the number of types on the pcp lists */
43 MIGRATE_HIGHATOMIC = MIGRATE_PCPTYPES,
46 * MIGRATE_CMA migration type is designed to mimic the way
47 * ZONE_MOVABLE works. Only movable pages can be allocated
48 * from MIGRATE_CMA pageblocks and page allocator never
49 * implicitly change migration type of MIGRATE_CMA pageblock.
51 * The way to use it is to change migratetype of a range of
52 * pageblocks to MIGRATE_CMA which can be done by
53 * __free_pageblock_cma() function. What is important though
54 * is that a range of pageblocks must be aligned to
55 * MAX_ORDER_NR_PAGES should biggest page be bigger then
60 #ifdef CONFIG_MEMORY_ISOLATION
61 MIGRATE_ISOLATE, /* can't allocate from here */
66 /* In mm/page_alloc.c; keep in sync also with show_migration_types() there */
67 extern char * const migratetype_names[MIGRATE_TYPES];
70 # define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA)
72 # define is_migrate_cma(migratetype) false
75 #define for_each_migratetype_order(order, type) \
76 for (order = 0; order < MAX_ORDER; order++) \
77 for (type = 0; type < MIGRATE_TYPES; type++)
79 extern int page_group_by_mobility_disabled;
81 #define NR_MIGRATETYPE_BITS (PB_migrate_end - PB_migrate + 1)
82 #define MIGRATETYPE_MASK ((1UL << NR_MIGRATETYPE_BITS) - 1)
84 #define get_pageblock_migratetype(page) \
85 get_pfnblock_flags_mask(page, page_to_pfn(page), \
86 PB_migrate_end, MIGRATETYPE_MASK)
88 static inline int get_pfnblock_migratetype(struct page *page, unsigned long pfn)
90 BUILD_BUG_ON(PB_migrate_end - PB_migrate != 2);
91 return get_pfnblock_flags_mask(page, pfn, PB_migrate_end,
96 struct list_head free_list[MIGRATE_TYPES];
97 unsigned long nr_free;
103 * zone->lock and zone->lru_lock are two of the hottest locks in the kernel.
104 * So add a wild amount of padding here to ensure that they fall into separate
105 * cachelines. There are very few zone structures in the machine, so space
106 * consumption is not a concern here.
108 #if defined(CONFIG_SMP)
109 struct zone_padding {
111 } ____cacheline_internodealigned_in_smp;
112 #define ZONE_PADDING(name) struct zone_padding name;
114 #define ZONE_PADDING(name)
117 enum zone_stat_item {
118 /* First 128 byte cacheline (assuming 64 bit words) */
122 NR_INACTIVE_ANON = NR_LRU_BASE, /* must match order of LRU_[IN]ACTIVE */
123 NR_ACTIVE_ANON, /* " " " " " */
124 NR_INACTIVE_FILE, /* " " " " " */
125 NR_ACTIVE_FILE, /* " " " " " */
126 NR_UNEVICTABLE, /* " " " " " */
127 NR_MLOCK, /* mlock()ed pages found and moved off LRU */
128 NR_ANON_PAGES, /* Mapped anonymous pages */
129 NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
130 only modified from process context */
135 NR_SLAB_UNRECLAIMABLE,
136 NR_PAGETABLE, /* used for pagetables */
138 /* Second 128 byte cacheline */
139 NR_UNSTABLE_NFS, /* NFS unstable pages */
142 NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */
143 NR_WRITEBACK_TEMP, /* Writeback using temporary buffers */
144 NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */
145 NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */
146 NR_SHMEM, /* shmem pages (included tmpfs/GEM pages) */
147 NR_DIRTIED, /* page dirtyings since bootup */
148 NR_WRITTEN, /* page writings since bootup */
149 NR_PAGES_SCANNED, /* pages scanned since last reclaim */
151 NUMA_HIT, /* allocated in intended node */
152 NUMA_MISS, /* allocated in non intended node */
153 NUMA_FOREIGN, /* was intended here, hit elsewhere */
154 NUMA_INTERLEAVE_HIT, /* interleaver preferred this zone */
155 NUMA_LOCAL, /* allocation from local node */
156 NUMA_OTHER, /* allocation from other node */
160 WORKINGSET_NODERECLAIM,
161 NR_ANON_TRANSPARENT_HUGEPAGES,
163 NR_VM_ZONE_STAT_ITEMS };
166 * We do arithmetic on the LRU lists in various places in the code,
167 * so it is important to keep the active lists LRU_ACTIVE higher in
168 * the array than the corresponding inactive lists, and to keep
169 * the *_FILE lists LRU_FILE higher than the corresponding _ANON lists.
171 * This has to be kept in sync with the statistics in zone_stat_item
172 * above and the descriptions in vmstat_text in mm/vmstat.c
179 LRU_INACTIVE_ANON = LRU_BASE,
180 LRU_ACTIVE_ANON = LRU_BASE + LRU_ACTIVE,
181 LRU_INACTIVE_FILE = LRU_BASE + LRU_FILE,
182 LRU_ACTIVE_FILE = LRU_BASE + LRU_FILE + LRU_ACTIVE,
187 #define for_each_lru(lru) for (lru = 0; lru < NR_LRU_LISTS; lru++)
189 #define for_each_evictable_lru(lru) for (lru = 0; lru <= LRU_ACTIVE_FILE; lru++)
191 static inline int is_file_lru(enum lru_list lru)
193 return (lru == LRU_INACTIVE_FILE || lru == LRU_ACTIVE_FILE);
196 static inline int is_active_lru(enum lru_list lru)
198 return (lru == LRU_ACTIVE_ANON || lru == LRU_ACTIVE_FILE);
201 struct zone_reclaim_stat {
203 * The pageout code in vmscan.c keeps track of how many of the
204 * mem/swap backed and file backed pages are referenced.
205 * The higher the rotated/scanned ratio, the more valuable
208 * The anon LRU stats live in [0], file LRU stats in [1]
210 unsigned long recent_rotated[2];
211 unsigned long recent_scanned[2];
215 struct list_head lists[NR_LRU_LISTS];
216 struct zone_reclaim_stat reclaim_stat;
217 /* Evictions & activations on the inactive file list */
218 atomic_long_t inactive_age;
224 /* Mask used at gathering information at once (see memcontrol.c) */
225 #define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE))
226 #define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON))
227 #define LRU_ALL ((1 << NR_LRU_LISTS) - 1)
229 /* Isolate clean file */
230 #define ISOLATE_CLEAN ((__force isolate_mode_t)0x1)
231 /* Isolate unmapped file */
232 #define ISOLATE_UNMAPPED ((__force isolate_mode_t)0x2)
233 /* Isolate for asynchronous migration */
234 #define ISOLATE_ASYNC_MIGRATE ((__force isolate_mode_t)0x4)
235 /* Isolate unevictable pages */
236 #define ISOLATE_UNEVICTABLE ((__force isolate_mode_t)0x8)
238 /* LRU Isolation modes. */
239 typedef unsigned __bitwise__ isolate_mode_t;
241 enum zone_watermarks {
248 #define min_wmark_pages(z) (z->watermark[WMARK_MIN])
249 #define low_wmark_pages(z) (z->watermark[WMARK_LOW])
250 #define high_wmark_pages(z) (z->watermark[WMARK_HIGH])
252 struct per_cpu_pages {
253 int count; /* number of pages in the list */
254 int high; /* high watermark, emptying needed */
255 int batch; /* chunk size for buddy add/remove */
257 /* Lists of pages, one per migrate type stored on the pcp-lists */
258 struct list_head lists[MIGRATE_PCPTYPES];
261 struct per_cpu_pageset {
262 struct per_cpu_pages pcp;
268 s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS];
272 #endif /* !__GENERATING_BOUNDS.H */
275 #ifdef CONFIG_ZONE_DMA
277 * ZONE_DMA is used when there are devices that are not able
278 * to do DMA to all of addressable memory (ZONE_NORMAL). Then we
279 * carve out the portion of memory that is needed for these devices.
280 * The range is arch specific.
285 * ---------------------------
286 * parisc, ia64, sparc <4G
289 * alpha Unlimited or 0-16MB.
291 * i386, x86_64 and multiple other arches
296 #ifdef CONFIG_ZONE_DMA32
298 * x86_64 needs two ZONE_DMAs because it supports devices that are
299 * only able to do DMA to the lower 16M but also 32 bit devices that
300 * can only do DMA areas below 4G.
305 * Normal addressable memory is in ZONE_NORMAL. DMA operations can be
306 * performed on pages in ZONE_NORMAL if the DMA devices support
307 * transfers to all addressable memory.
310 #ifdef CONFIG_HIGHMEM
312 * A memory area that is only addressable by the kernel through
313 * mapping portions into its own address space. This is for example
314 * used by i386 to allow the kernel to address the memory beyond
315 * 900MB. The kernel will set up special mappings (page
316 * table entries on i386) for each page that the kernel needs to
322 #ifdef CONFIG_ZONE_DEVICE
329 #ifndef __GENERATING_BOUNDS_H
332 /* Read-mostly fields */
334 /* zone watermarks, access with *_wmark_pages(zone) macros */
335 unsigned long watermark[NR_WMARK];
337 unsigned long nr_reserved_highatomic;
340 * We don't know if the memory that we're going to allocate will be
341 * freeable or/and it will be released eventually, so to avoid totally
342 * wasting several GB of ram we must reserve some of the lower zone
343 * memory (otherwise we risk to run OOM on the lower zones despite
344 * there being tons of freeable ram on the higher zones). This array is
345 * recalculated at runtime if the sysctl_lowmem_reserve_ratio sysctl
348 long lowmem_reserve[MAX_NR_ZONES];
355 * The target ratio of ACTIVE_ANON to INACTIVE_ANON pages on
356 * this zone's LRU. Maintained by the pageout code.
358 unsigned int inactive_ratio;
360 struct pglist_data *zone_pgdat;
361 struct per_cpu_pageset __percpu *pageset;
364 * This is a per-zone reserve of pages that are not available
365 * to userspace allocations.
367 unsigned long totalreserve_pages;
369 #ifndef CONFIG_SPARSEMEM
371 * Flags for a pageblock_nr_pages block. See pageblock-flags.h.
372 * In SPARSEMEM, this map is stored in struct mem_section
374 unsigned long *pageblock_flags;
375 #endif /* CONFIG_SPARSEMEM */
379 * zone reclaim becomes active if more unmapped pages exist.
381 unsigned long min_unmapped_pages;
382 unsigned long min_slab_pages;
383 #endif /* CONFIG_NUMA */
385 /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
386 unsigned long zone_start_pfn;
389 * spanned_pages is the total pages spanned by the zone, including
390 * holes, which is calculated as:
391 * spanned_pages = zone_end_pfn - zone_start_pfn;
393 * present_pages is physical pages existing within the zone, which
395 * present_pages = spanned_pages - absent_pages(pages in holes);
397 * managed_pages is present pages managed by the buddy system, which
398 * is calculated as (reserved_pages includes pages allocated by the
399 * bootmem allocator):
400 * managed_pages = present_pages - reserved_pages;
402 * So present_pages may be used by memory hotplug or memory power
403 * management logic to figure out unmanaged pages by checking
404 * (present_pages - managed_pages). And managed_pages should be used
405 * by page allocator and vm scanner to calculate all kinds of watermarks
410 * zone_start_pfn and spanned_pages are protected by span_seqlock.
411 * It is a seqlock because it has to be read outside of zone->lock,
412 * and it is done in the main allocator path. But, it is written
413 * quite infrequently.
415 * The span_seq lock is declared along with zone->lock because it is
416 * frequently read in proximity to zone->lock. It's good to
417 * give them a chance of being in the same cacheline.
419 * Write access to present_pages at runtime should be protected by
420 * mem_hotplug_begin/end(). Any reader who can't tolerant drift of
421 * present_pages should get_online_mems() to get a stable value.
423 * Read access to managed_pages should be safe because it's unsigned
424 * long. Write access to zone->managed_pages and totalram_pages are
425 * protected by managed_page_count_lock at runtime. Idealy only
426 * adjust_managed_page_count() should be used instead of directly
427 * touching zone->managed_pages and totalram_pages.
429 unsigned long managed_pages;
430 unsigned long spanned_pages;
431 unsigned long present_pages;
435 #ifdef CONFIG_MEMORY_ISOLATION
437 * Number of isolated pageblock. It is used to solve incorrect
438 * freepage counting problem due to racy retrieving migratetype
439 * of pageblock. Protected by zone->lock.
441 unsigned long nr_isolate_pageblock;
444 #ifdef CONFIG_MEMORY_HOTPLUG
445 /* see spanned/present_pages for more description */
446 seqlock_t span_seqlock;
450 * wait_table -- the array holding the hash table
451 * wait_table_hash_nr_entries -- the size of the hash table array
452 * wait_table_bits -- wait_table_size == (1 << wait_table_bits)
454 * The purpose of all these is to keep track of the people
455 * waiting for a page to become available and make them
456 * runnable again when possible. The trouble is that this
457 * consumes a lot of space, especially when so few things
458 * wait on pages at a given time. So instead of using
459 * per-page waitqueues, we use a waitqueue hash table.
461 * The bucket discipline is to sleep on the same queue when
462 * colliding and wake all in that wait queue when removing.
463 * When something wakes, it must check to be sure its page is
464 * truly available, a la thundering herd. The cost of a
465 * collision is great, but given the expected load of the
466 * table, they should be so rare as to be outweighed by the
467 * benefits from the saved space.
469 * __wait_on_page_locked() and unlock_page() in mm/filemap.c, are the
470 * primary users of these fields, and in mm/page_alloc.c
471 * free_area_init_core() performs the initialization of them.
473 wait_queue_head_t *wait_table;
474 unsigned long wait_table_hash_nr_entries;
475 unsigned long wait_table_bits;
478 /* free areas of different sizes */
479 struct free_area free_area[MAX_ORDER];
481 /* zone flags, see below */
484 /* Write-intensive fields used from the page allocator */
489 /* Write-intensive fields used by page reclaim */
491 /* Fields commonly accessed by the page reclaim scanner */
493 struct lruvec lruvec;
496 * When free pages are below this point, additional steps are taken
497 * when reading the number of free pages to avoid per-cpu counter
498 * drift allowing watermarks to be breached
500 unsigned long percpu_drift_mark;
502 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
503 /* pfn where compaction free scanner should start */
504 unsigned long compact_cached_free_pfn;
505 /* pfn where async and sync compaction migration scanner should start */
506 unsigned long compact_cached_migrate_pfn[2];
509 #ifdef CONFIG_COMPACTION
511 * On compaction failure, 1<<compact_defer_shift compactions
512 * are skipped before trying again. The number attempted since
513 * last failure is tracked with compact_considered.
515 unsigned int compact_considered;
516 unsigned int compact_defer_shift;
517 int compact_order_failed;
520 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
521 /* Set to true when the PG_migrate_skip bits should be cleared */
522 bool compact_blockskip_flush;
526 /* Zone statistics */
527 atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
528 } ____cacheline_internodealigned_in_smp;
531 ZONE_RECLAIM_LOCKED, /* prevents concurrent reclaim */
532 ZONE_OOM_LOCKED, /* zone is in OOM killer zonelist */
533 ZONE_CONGESTED, /* zone has many dirty pages backed by
536 ZONE_DIRTY, /* reclaim scanning has recently found
537 * many dirty file pages at the tail
540 ZONE_WRITEBACK, /* reclaim scanning has recently found
541 * many pages under writeback
543 ZONE_FAIR_DEPLETED, /* fair zone policy batch depleted */
546 static inline unsigned long zone_end_pfn(const struct zone *zone)
548 return zone->zone_start_pfn + zone->spanned_pages;
551 static inline bool zone_spans_pfn(const struct zone *zone, unsigned long pfn)
553 return zone->zone_start_pfn <= pfn && pfn < zone_end_pfn(zone);
556 static inline bool zone_is_initialized(struct zone *zone)
558 return !!zone->wait_table;
561 static inline bool zone_is_empty(struct zone *zone)
563 return zone->spanned_pages == 0;
567 * The "priority" of VM scanning is how much of the queues we will scan in one
568 * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
569 * queues ("queue_length >> 12") during an aging round.
571 #define DEF_PRIORITY 12
573 /* Maximum number of zones on a zonelist */
574 #define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
577 ZONELIST_FALLBACK, /* zonelist with fallback */
580 * The NUMA zonelists are doubled because we need zonelists that
581 * restrict the allocations to a single node for __GFP_THISNODE.
583 ZONELIST_NOFALLBACK, /* zonelist without fallback (__GFP_THISNODE) */
589 * This struct contains information about a zone in a zonelist. It is stored
590 * here to avoid dereferences into large structures and lookups of tables
593 struct zone *zone; /* Pointer to actual zone */
594 int zone_idx; /* zone_idx(zoneref->zone) */
598 * One allocation request operates on a zonelist. A zonelist
599 * is a list of zones, the first one is the 'goal' of the
600 * allocation, the other zones are fallback zones, in decreasing
603 * To speed the reading of the zonelist, the zonerefs contain the zone index
604 * of the entry being read. Helper functions to access information given
605 * a struct zoneref are
607 * zonelist_zone() - Return the struct zone * for an entry in _zonerefs
608 * zonelist_zone_idx() - Return the index of the zone for an entry
609 * zonelist_node_idx() - Return the index of the node for an entry
612 struct zoneref _zonerefs[MAX_ZONES_PER_ZONELIST + 1];
615 #ifndef CONFIG_DISCONTIGMEM
616 /* The array of struct pages - for discontigmem use pgdat->lmem_map */
617 extern struct page *mem_map;
621 * The pg_data_t structure is used in machines with CONFIG_DISCONTIGMEM
622 * (mostly NUMA machines?) to denote a higher-level memory zone than the
625 * On NUMA machines, each NUMA node would have a pg_data_t to describe
626 * it's memory layout.
628 * Memory statistics and page replacement data structures are maintained on a
632 typedef struct pglist_data {
633 struct zone node_zones[MAX_NR_ZONES];
634 struct zonelist node_zonelists[MAX_ZONELISTS];
636 #ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */
637 struct page *node_mem_map;
638 #ifdef CONFIG_PAGE_EXTENSION
639 struct page_ext *node_page_ext;
642 #ifndef CONFIG_NO_BOOTMEM
643 struct bootmem_data *bdata;
645 #ifdef CONFIG_MEMORY_HOTPLUG
647 * Must be held any time you expect node_start_pfn, node_present_pages
648 * or node_spanned_pages stay constant. Holding this will also
649 * guarantee that any pfn_valid() stays that way.
651 * pgdat_resize_lock() and pgdat_resize_unlock() are provided to
652 * manipulate node_size_lock without checking for CONFIG_MEMORY_HOTPLUG.
654 * Nests above zone->lock and zone->span_seqlock
656 spinlock_t node_size_lock;
658 unsigned long node_start_pfn;
659 unsigned long node_present_pages; /* total number of physical pages */
660 unsigned long node_spanned_pages; /* total size of physical page
661 range, including holes */
663 wait_queue_head_t kswapd_wait;
664 wait_queue_head_t pfmemalloc_wait;
665 struct task_struct *kswapd; /* Protected by
666 mem_hotplug_begin/end() */
667 int kswapd_max_order;
668 enum zone_type classzone_idx;
669 #ifdef CONFIG_NUMA_BALANCING
670 /* Lock serializing the migrate rate limiting window */
671 spinlock_t numabalancing_migrate_lock;
673 /* Rate limiting time interval */
674 unsigned long numabalancing_migrate_next_window;
676 /* Number of pages migrated during the rate limiting time interval */
677 unsigned long numabalancing_migrate_nr_pages;
680 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
682 * If memory initialisation on large machines is deferred then this
683 * is the first PFN that needs to be initialised.
685 unsigned long first_deferred_pfn;
686 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
688 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
689 spinlock_t split_queue_lock;
690 struct list_head split_queue;
691 unsigned long split_queue_len;
695 #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
696 #define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)
697 #ifdef CONFIG_FLAT_NODE_MEM_MAP
698 #define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr))
700 #define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr))
702 #define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr))
704 #define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)
705 #define node_end_pfn(nid) pgdat_end_pfn(NODE_DATA(nid))
707 static inline unsigned long pgdat_end_pfn(pg_data_t *pgdat)
709 return pgdat->node_start_pfn + pgdat->node_spanned_pages;
712 static inline bool pgdat_is_empty(pg_data_t *pgdat)
714 return !pgdat->node_start_pfn && !pgdat->node_spanned_pages;
717 static inline int zone_id(const struct zone *zone)
719 struct pglist_data *pgdat = zone->zone_pgdat;
721 return zone - pgdat->node_zones;
724 #ifdef CONFIG_ZONE_DEVICE
725 static inline bool is_dev_zone(const struct zone *zone)
727 return zone_id(zone) == ZONE_DEVICE;
730 static inline bool is_dev_zone(const struct zone *zone)
736 #include <linux/memory_hotplug.h>
738 extern struct mutex zonelists_mutex;
739 void build_all_zonelists(pg_data_t *pgdat, struct zone *zone);
740 void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx);
741 bool zone_watermark_ok(struct zone *z, unsigned int order,
742 unsigned long mark, int classzone_idx, int alloc_flags);
743 bool zone_watermark_ok_safe(struct zone *z, unsigned int order,
744 unsigned long mark, int classzone_idx);
745 enum memmap_context {
749 extern int init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,
752 extern void lruvec_init(struct lruvec *lruvec);
754 static inline struct zone *lruvec_zone(struct lruvec *lruvec)
759 return container_of(lruvec, struct zone, lruvec);
763 extern unsigned long lruvec_lru_size(struct lruvec *lruvec, enum lru_list lru);
765 #ifdef CONFIG_HAVE_MEMORY_PRESENT
766 void memory_present(int nid, unsigned long start, unsigned long end);
768 static inline void memory_present(int nid, unsigned long start, unsigned long end) {}
771 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
772 int local_memory_node(int node_id);
774 static inline int local_memory_node(int node_id) { return node_id; };
777 #ifdef CONFIG_NEED_NODE_MEMMAP_SIZE
778 unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
782 * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
784 #define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
786 static inline int populated_zone(struct zone *zone)
788 return (!!zone->present_pages);
791 extern int movable_zone;
793 #ifdef CONFIG_HIGHMEM
794 static inline int zone_movable_is_highmem(void)
796 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
797 return movable_zone == ZONE_HIGHMEM;
799 return (ZONE_MOVABLE - 1) == ZONE_HIGHMEM;
804 static inline int is_highmem_idx(enum zone_type idx)
806 #ifdef CONFIG_HIGHMEM
807 return (idx == ZONE_HIGHMEM ||
808 (idx == ZONE_MOVABLE && zone_movable_is_highmem()));
815 * is_highmem - helper function to quickly check if a struct zone is a
816 * highmem zone or not. This is an attempt to keep references
817 * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
818 * @zone - pointer to struct zone variable
820 static inline int is_highmem(struct zone *zone)
822 #ifdef CONFIG_HIGHMEM
823 int zone_off = (char *)zone - (char *)zone->zone_pgdat->node_zones;
824 return zone_off == ZONE_HIGHMEM * sizeof(*zone) ||
825 (zone_off == ZONE_MOVABLE * sizeof(*zone) &&
826 zone_movable_is_highmem());
832 /* These two functions are used to setup the per zone pages min values */
834 int min_free_kbytes_sysctl_handler(struct ctl_table *, int,
835 void __user *, size_t *, loff_t *);
836 extern int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1];
837 int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *, int,
838 void __user *, size_t *, loff_t *);
839 int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *, int,
840 void __user *, size_t *, loff_t *);
841 int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *, int,
842 void __user *, size_t *, loff_t *);
843 int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *, int,
844 void __user *, size_t *, loff_t *);
846 extern int numa_zonelist_order_handler(struct ctl_table *, int,
847 void __user *, size_t *, loff_t *);
848 extern char numa_zonelist_order[];
849 #define NUMA_ZONELIST_ORDER_LEN 16 /* string buffer size */
851 #ifndef CONFIG_NEED_MULTIPLE_NODES
853 extern struct pglist_data contig_page_data;
854 #define NODE_DATA(nid) (&contig_page_data)
855 #define NODE_MEM_MAP(nid) mem_map
857 #else /* CONFIG_NEED_MULTIPLE_NODES */
859 #include <asm/mmzone.h>
861 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
863 extern struct pglist_data *first_online_pgdat(void);
864 extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat);
865 extern struct zone *next_zone(struct zone *zone);
868 * for_each_online_pgdat - helper macro to iterate over all online nodes
869 * @pgdat - pointer to a pg_data_t variable
871 #define for_each_online_pgdat(pgdat) \
872 for (pgdat = first_online_pgdat(); \
874 pgdat = next_online_pgdat(pgdat))
876 * for_each_zone - helper macro to iterate over all memory zones
877 * @zone - pointer to struct zone variable
879 * The user only needs to declare the zone variable, for_each_zone
882 #define for_each_zone(zone) \
883 for (zone = (first_online_pgdat())->node_zones; \
885 zone = next_zone(zone))
887 #define for_each_populated_zone(zone) \
888 for (zone = (first_online_pgdat())->node_zones; \
890 zone = next_zone(zone)) \
891 if (!populated_zone(zone)) \
895 static inline struct zone *zonelist_zone(struct zoneref *zoneref)
897 return zoneref->zone;
900 static inline int zonelist_zone_idx(struct zoneref *zoneref)
902 return zoneref->zone_idx;
905 static inline int zonelist_node_idx(struct zoneref *zoneref)
908 /* zone_to_nid not available in this context */
909 return zoneref->zone->node;
912 #endif /* CONFIG_NUMA */
916 * 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
917 * @z - The cursor used as a starting point for the search
918 * @highest_zoneidx - The zone index of the highest zone to return
919 * @nodes - An optional nodemask to filter the zonelist with
921 * This function returns the next zone at or below a given zone index that is
922 * within the allowed nodemask using a cursor as the starting point for the
923 * search. The zoneref returned is a cursor that represents the current zone
924 * being examined. It should be advanced by one before calling
925 * next_zones_zonelist again.
927 struct zoneref *next_zones_zonelist(struct zoneref *z,
928 enum zone_type highest_zoneidx,
932 * first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nodemask in a zonelist
933 * @zonelist - The zonelist to search for a suitable zone
934 * @highest_zoneidx - The zone index of the highest zone to return
935 * @nodes - An optional nodemask to filter the zonelist with
936 * @zone - The first suitable zone found is returned via this parameter
938 * This function returns the first zone at or below a given zone index that is
939 * within the allowed nodemask. The zoneref returned is a cursor that can be
940 * used to iterate the zonelist with next_zones_zonelist by advancing it by
941 * one before calling.
943 static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist,
944 enum zone_type highest_zoneidx,
948 struct zoneref *z = next_zones_zonelist(zonelist->_zonerefs,
949 highest_zoneidx, nodes);
950 *zone = zonelist_zone(z);
955 * 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
956 * @zone - The current zone in the iterator
957 * @z - The current pointer within zonelist->zones being iterated
958 * @zlist - The zonelist being iterated
959 * @highidx - The zone index of the highest zone to return
960 * @nodemask - Nodemask allowed by the allocator
962 * This iterator iterates though all zones at or below a given zone index and
963 * within a given nodemask
965 #define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
966 for (z = first_zones_zonelist(zlist, highidx, nodemask, &zone); \
968 z = next_zones_zonelist(++z, highidx, nodemask), \
969 zone = zonelist_zone(z)) \
972 * for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index
973 * @zone - The current zone in the iterator
974 * @z - The current pointer within zonelist->zones being iterated
975 * @zlist - The zonelist being iterated
976 * @highidx - The zone index of the highest zone to return
978 * This iterator iterates though all zones at or below a given zone index.
980 #define for_each_zone_zonelist(zone, z, zlist, highidx) \
981 for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)
983 #ifdef CONFIG_SPARSEMEM
984 #include <asm/sparsemem.h>
987 #if !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) && \
988 !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP)
989 static inline unsigned long early_pfn_to_nid(unsigned long pfn)
995 #ifdef CONFIG_FLATMEM
996 #define pfn_to_nid(pfn) (0)
999 #ifdef CONFIG_SPARSEMEM
1002 * SECTION_SHIFT #bits space required to store a section #
1004 * PA_SECTION_SHIFT physical address to/from section number
1005 * PFN_SECTION_SHIFT pfn to/from section number
1007 #define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
1008 #define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)
1010 #define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
1012 #define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)
1013 #define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))
1015 #define SECTION_BLOCKFLAGS_BITS \
1016 ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS)
1018 #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
1019 #error Allocator MAX_ORDER exceeds SECTION_SIZE
1022 #define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
1023 #define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
1025 #define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)
1026 #define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)
1030 struct mem_section {
1032 * This is, logically, a pointer to an array of struct
1033 * pages. However, it is stored with some other magic.
1034 * (see sparse.c::sparse_init_one_section())
1036 * Additionally during early boot we encode node id of
1037 * the location of the section here to guide allocation.
1038 * (see sparse.c::memory_present())
1040 * Making it a UL at least makes someone do a cast
1041 * before using it wrong.
1043 unsigned long section_mem_map;
1045 /* See declaration of similar field in struct zone */
1046 unsigned long *pageblock_flags;
1047 #ifdef CONFIG_PAGE_EXTENSION
1049 * If !SPARSEMEM, pgdat doesn't have page_ext pointer. We use
1050 * section. (see page_ext.h about this.)
1052 struct page_ext *page_ext;
1056 * WARNING: mem_section must be a power-of-2 in size for the
1057 * calculation and use of SECTION_ROOT_MASK to make sense.
1061 #ifdef CONFIG_SPARSEMEM_EXTREME
1062 #define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))
1064 #define SECTIONS_PER_ROOT 1
1067 #define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
1068 #define NR_SECTION_ROOTS DIV_ROUND_UP(NR_MEM_SECTIONS, SECTIONS_PER_ROOT)
1069 #define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)
1071 #ifdef CONFIG_SPARSEMEM_EXTREME
1072 extern struct mem_section *mem_section[NR_SECTION_ROOTS];
1074 extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
1077 static inline struct mem_section *__nr_to_section(unsigned long nr)
1079 if (!mem_section[SECTION_NR_TO_ROOT(nr)])
1081 return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK];
1083 extern int __section_nr(struct mem_section* ms);
1084 extern unsigned long usemap_size(void);
1087 * We use the lower bits of the mem_map pointer to store
1088 * a little bit of information. There should be at least
1089 * 3 bits here due to 32-bit alignment.
1091 #define SECTION_MARKED_PRESENT (1UL<<0)
1092 #define SECTION_HAS_MEM_MAP (1UL<<1)
1093 #define SECTION_MAP_LAST_BIT (1UL<<2)
1094 #define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1))
1095 #define SECTION_NID_SHIFT 2
1097 static inline struct page *__section_mem_map_addr(struct mem_section *section)
1099 unsigned long map = section->section_mem_map;
1100 map &= SECTION_MAP_MASK;
1101 return (struct page *)map;
1104 static inline int present_section(struct mem_section *section)
1106 return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));
1109 static inline int present_section_nr(unsigned long nr)
1111 return present_section(__nr_to_section(nr));
1114 static inline int valid_section(struct mem_section *section)
1116 return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));
1119 static inline int valid_section_nr(unsigned long nr)
1121 return valid_section(__nr_to_section(nr));
1124 static inline struct mem_section *__pfn_to_section(unsigned long pfn)
1126 return __nr_to_section(pfn_to_section_nr(pfn));
1129 #ifndef CONFIG_HAVE_ARCH_PFN_VALID
1130 static inline int pfn_valid(unsigned long pfn)
1132 if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
1134 return valid_section(__nr_to_section(pfn_to_section_nr(pfn)));
1138 static inline int pfn_present(unsigned long pfn)
1140 if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
1142 return present_section(__nr_to_section(pfn_to_section_nr(pfn)));
1146 * These are _only_ used during initialisation, therefore they
1147 * can use __initdata ... They could have names to indicate
1151 #define pfn_to_nid(pfn) \
1153 unsigned long __pfn_to_nid_pfn = (pfn); \
1154 page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \
1157 #define pfn_to_nid(pfn) (0)
1160 #define early_pfn_valid(pfn) pfn_valid(pfn)
1161 void sparse_init(void);
1163 #define sparse_init() do {} while (0)
1164 #define sparse_index_init(_sec, _nid) do {} while (0)
1165 #endif /* CONFIG_SPARSEMEM */
1168 * During memory init memblocks map pfns to nids. The search is expensive and
1169 * this caches recent lookups. The implementation of __early_pfn_to_nid
1170 * may treat start/end as pfns or sections.
1172 struct mminit_pfnnid_cache {
1173 unsigned long last_start;
1174 unsigned long last_end;
1178 #ifndef early_pfn_valid
1179 #define early_pfn_valid(pfn) (1)
1182 void memory_present(int nid, unsigned long start, unsigned long end);
1183 unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
1186 * If it is possible to have holes within a MAX_ORDER_NR_PAGES, then we
1187 * need to check pfn validility within that MAX_ORDER_NR_PAGES block.
1188 * pfn_valid_within() should be used in this case; we optimise this away
1189 * when we have no holes within a MAX_ORDER_NR_PAGES block.
1191 #ifdef CONFIG_HOLES_IN_ZONE
1192 #define pfn_valid_within(pfn) pfn_valid(pfn)
1194 #define pfn_valid_within(pfn) (1)
1197 #ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
1199 * pfn_valid() is meant to be able to tell if a given PFN has valid memmap
1200 * associated with it or not. In FLATMEM, it is expected that holes always
1201 * have valid memmap as long as there is valid PFNs either side of the hole.
1202 * In SPARSEMEM, it is assumed that a valid section has a memmap for the
1205 * However, an ARM, and maybe other embedded architectures in the future
1206 * free memmap backing holes to save memory on the assumption the memmap is
1207 * never used. The page_zone linkages are then broken even though pfn_valid()
1208 * returns true. A walker of the full memmap must then do this additional
1209 * check to ensure the memmap they are looking at is sane by making sure
1210 * the zone and PFN linkages are still valid. This is expensive, but walkers
1211 * of the full memmap are extremely rare.
1213 bool memmap_valid_within(unsigned long pfn,
1214 struct page *page, struct zone *zone);
1216 static inline bool memmap_valid_within(unsigned long pfn,
1217 struct page *page, struct zone *zone)
1221 #endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
1223 #endif /* !__GENERATING_BOUNDS.H */
1224 #endif /* !__ASSEMBLY__ */
1225 #endif /* _LINUX_MMZONE_H */