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 <generated/bounds.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 * coelesce naturally under reasonable reclaim pressure and those which
36 #define PAGE_ALLOC_COSTLY_ORDER 3
38 #define MIGRATE_UNMOVABLE 0
39 #define MIGRATE_RECLAIMABLE 1
40 #define MIGRATE_MOVABLE 2
41 #define MIGRATE_PCPTYPES 3 /* the number of types on the pcp lists */
42 #define MIGRATE_RESERVE 3
43 #define MIGRATE_ISOLATE 4 /* can't allocate from here */
44 #define MIGRATE_TYPES 5
46 #define for_each_migratetype_order(order, type) \
47 for (order = 0; order < MAX_ORDER; order++) \
48 for (type = 0; type < MIGRATE_TYPES; type++)
50 extern int page_group_by_mobility_disabled;
52 static inline int get_pageblock_migratetype(struct page *page)
54 return get_pageblock_flags_group(page, PB_migrate, PB_migrate_end);
58 struct list_head free_list[MIGRATE_TYPES];
59 unsigned long nr_free;
65 * zone->lock and zone->lru_lock are two of the hottest locks in the kernel.
66 * So add a wild amount of padding here to ensure that they fall into separate
67 * cachelines. There are very few zone structures in the machine, so space
68 * consumption is not a concern here.
70 #if defined(CONFIG_SMP)
73 } ____cacheline_internodealigned_in_smp;
74 #define ZONE_PADDING(name) struct zone_padding name;
76 #define ZONE_PADDING(name)
80 /* First 128 byte cacheline (assuming 64 bit words) */
83 NR_INACTIVE_ANON = NR_LRU_BASE, /* must match order of LRU_[IN]ACTIVE */
84 NR_ACTIVE_ANON, /* " " " " " */
85 NR_INACTIVE_FILE, /* " " " " " */
86 NR_ACTIVE_FILE, /* " " " " " */
87 NR_UNEVICTABLE, /* " " " " " */
88 NR_MLOCK, /* mlock()ed pages found and moved off LRU */
89 NR_ANON_PAGES, /* Mapped anonymous pages */
90 NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
91 only modified from process context */
96 NR_SLAB_UNRECLAIMABLE,
97 NR_PAGETABLE, /* used for pagetables */
99 /* Second 128 byte cacheline */
100 NR_UNSTABLE_NFS, /* NFS unstable pages */
103 NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */
104 NR_WRITEBACK_TEMP, /* Writeback using temporary buffers */
105 NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */
106 NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */
107 NR_SHMEM, /* shmem pages (included tmpfs/GEM pages) */
108 NR_DIRTIED, /* page dirtyings since bootup */
109 NR_WRITTEN, /* page writings since bootup */
111 NUMA_HIT, /* allocated in intended node */
112 NUMA_MISS, /* allocated in non intended node */
113 NUMA_FOREIGN, /* was intended here, hit elsewhere */
114 NUMA_INTERLEAVE_HIT, /* interleaver preferred this zone */
115 NUMA_LOCAL, /* allocation from local node */
116 NUMA_OTHER, /* allocation from other node */
118 NR_ANON_TRANSPARENT_HUGEPAGES,
119 NR_VM_ZONE_STAT_ITEMS };
122 * We do arithmetic on the LRU lists in various places in the code,
123 * so it is important to keep the active lists LRU_ACTIVE higher in
124 * the array than the corresponding inactive lists, and to keep
125 * the *_FILE lists LRU_FILE higher than the corresponding _ANON lists.
127 * This has to be kept in sync with the statistics in zone_stat_item
128 * above and the descriptions in vmstat_text in mm/vmstat.c
135 LRU_INACTIVE_ANON = LRU_BASE,
136 LRU_ACTIVE_ANON = LRU_BASE + LRU_ACTIVE,
137 LRU_INACTIVE_FILE = LRU_BASE + LRU_FILE,
138 LRU_ACTIVE_FILE = LRU_BASE + LRU_FILE + LRU_ACTIVE,
143 #define for_each_lru(l) for (l = 0; l < NR_LRU_LISTS; l++)
145 #define for_each_evictable_lru(l) for (l = 0; l <= LRU_ACTIVE_FILE; l++)
147 static inline int is_file_lru(enum lru_list l)
149 return (l == LRU_INACTIVE_FILE || l == LRU_ACTIVE_FILE);
152 static inline int is_active_lru(enum lru_list l)
154 return (l == LRU_ACTIVE_ANON || l == LRU_ACTIVE_FILE);
157 static inline int is_unevictable_lru(enum lru_list l)
159 return (l == LRU_UNEVICTABLE);
162 /* Mask used at gathering information at once (see memcontrol.c) */
163 #define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE))
164 #define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON))
165 #define LRU_ALL_EVICTABLE (LRU_ALL_FILE | LRU_ALL_ANON)
166 #define LRU_ALL ((1 << NR_LRU_LISTS) - 1)
168 /* Isolate inactive pages */
169 #define ISOLATE_INACTIVE ((__force isolate_mode_t)0x1)
170 /* Isolate active pages */
171 #define ISOLATE_ACTIVE ((__force isolate_mode_t)0x2)
172 /* Isolate clean file */
173 #define ISOLATE_CLEAN ((__force isolate_mode_t)0x4)
174 /* Isolate unmapped file */
175 #define ISOLATE_UNMAPPED ((__force isolate_mode_t)0x8)
176 /* Isolate for asynchronous migration */
177 #define ISOLATE_ASYNC_MIGRATE ((__force isolate_mode_t)0x10)
179 /* LRU Isolation modes. */
180 typedef unsigned __bitwise__ isolate_mode_t;
182 enum zone_watermarks {
189 #define min_wmark_pages(z) (z->watermark[WMARK_MIN])
190 #define low_wmark_pages(z) (z->watermark[WMARK_LOW])
191 #define high_wmark_pages(z) (z->watermark[WMARK_HIGH])
193 struct per_cpu_pages {
194 int count; /* number of pages in the list */
195 int high; /* high watermark, emptying needed */
196 int batch; /* chunk size for buddy add/remove */
198 /* Lists of pages, one per migrate type stored on the pcp-lists */
199 struct list_head lists[MIGRATE_PCPTYPES];
202 struct per_cpu_pageset {
203 struct per_cpu_pages pcp;
209 s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS];
213 #endif /* !__GENERATING_BOUNDS.H */
216 #ifdef CONFIG_ZONE_DMA
218 * ZONE_DMA is used when there are devices that are not able
219 * to do DMA to all of addressable memory (ZONE_NORMAL). Then we
220 * carve out the portion of memory that is needed for these devices.
221 * The range is arch specific.
226 * ---------------------------
227 * parisc, ia64, sparc <4G
230 * alpha Unlimited or 0-16MB.
232 * i386, x86_64 and multiple other arches
237 #ifdef CONFIG_ZONE_DMA32
239 * x86_64 needs two ZONE_DMAs because it supports devices that are
240 * only able to do DMA to the lower 16M but also 32 bit devices that
241 * can only do DMA areas below 4G.
246 * Normal addressable memory is in ZONE_NORMAL. DMA operations can be
247 * performed on pages in ZONE_NORMAL if the DMA devices support
248 * transfers to all addressable memory.
251 #ifdef CONFIG_HIGHMEM
253 * A memory area that is only addressable by the kernel through
254 * mapping portions into its own address space. This is for example
255 * used by i386 to allow the kernel to address the memory beyond
256 * 900MB. The kernel will set up special mappings (page
257 * table entries on i386) for each page that the kernel needs to
266 #ifndef __GENERATING_BOUNDS_H
269 * When a memory allocation must conform to specific limitations (such
270 * as being suitable for DMA) the caller will pass in hints to the
271 * allocator in the gfp_mask, in the zone modifier bits. These bits
272 * are used to select a priority ordered list of memory zones which
273 * match the requested limits. See gfp_zone() in include/linux/gfp.h
277 #define ZONES_SHIFT 0
278 #elif MAX_NR_ZONES <= 2
279 #define ZONES_SHIFT 1
280 #elif MAX_NR_ZONES <= 4
281 #define ZONES_SHIFT 2
283 #error ZONES_SHIFT -- too many zones configured adjust calculation
286 struct zone_reclaim_stat {
288 * The pageout code in vmscan.c keeps track of how many of the
289 * mem/swap backed and file backed pages are refeferenced.
290 * The higher the rotated/scanned ratio, the more valuable
293 * The anon LRU stats live in [0], file LRU stats in [1]
295 unsigned long recent_rotated[2];
296 unsigned long recent_scanned[2];
300 /* Fields commonly accessed by the page allocator */
302 /* zone watermarks, access with *_wmark_pages(zone) macros */
303 unsigned long watermark[NR_WMARK];
306 * When free pages are below this point, additional steps are taken
307 * when reading the number of free pages to avoid per-cpu counter
308 * drift allowing watermarks to be breached
310 unsigned long percpu_drift_mark;
313 * We don't know if the memory that we're going to allocate will be freeable
314 * or/and it will be released eventually, so to avoid totally wasting several
315 * GB of ram we must reserve some of the lower zone memory (otherwise we risk
316 * to run OOM on the lower zones despite there's tons of freeable ram
317 * on the higher zones). This array is recalculated at runtime if the
318 * sysctl_lowmem_reserve_ratio sysctl changes.
320 unsigned long lowmem_reserve[MAX_NR_ZONES];
325 * zone reclaim becomes active if more unmapped pages exist.
327 unsigned long min_unmapped_pages;
328 unsigned long min_slab_pages;
330 struct per_cpu_pageset __percpu *pageset;
332 * free areas of different sizes
335 int all_unreclaimable; /* All pages pinned */
336 #ifdef CONFIG_MEMORY_HOTPLUG
337 /* see spanned/present_pages for more description */
338 seqlock_t span_seqlock;
340 struct free_area free_area[MAX_ORDER];
342 #ifndef CONFIG_SPARSEMEM
344 * Flags for a pageblock_nr_pages block. See pageblock-flags.h.
345 * In SPARSEMEM, this map is stored in struct mem_section
347 unsigned long *pageblock_flags;
348 #endif /* CONFIG_SPARSEMEM */
350 #ifdef CONFIG_COMPACTION
352 * On compaction failure, 1<<compact_defer_shift compactions
353 * are skipped before trying again. The number attempted since
354 * last failure is tracked with compact_considered.
356 unsigned int compact_considered;
357 unsigned int compact_defer_shift;
362 /* Fields commonly accessed by the page reclaim scanner */
365 struct list_head list;
368 struct zone_reclaim_stat reclaim_stat;
370 unsigned long pages_scanned; /* since last reclaim */
371 unsigned long flags; /* zone flags, see below */
373 /* Zone statistics */
374 atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
377 * The target ratio of ACTIVE_ANON to INACTIVE_ANON pages on
378 * this zone's LRU. Maintained by the pageout code.
380 unsigned int inactive_ratio;
384 /* Rarely used or read-mostly fields */
387 * wait_table -- the array holding the hash table
388 * wait_table_hash_nr_entries -- the size of the hash table array
389 * wait_table_bits -- wait_table_size == (1 << wait_table_bits)
391 * The purpose of all these is to keep track of the people
392 * waiting for a page to become available and make them
393 * runnable again when possible. The trouble is that this
394 * consumes a lot of space, especially when so few things
395 * wait on pages at a given time. So instead of using
396 * per-page waitqueues, we use a waitqueue hash table.
398 * The bucket discipline is to sleep on the same queue when
399 * colliding and wake all in that wait queue when removing.
400 * When something wakes, it must check to be sure its page is
401 * truly available, a la thundering herd. The cost of a
402 * collision is great, but given the expected load of the
403 * table, they should be so rare as to be outweighed by the
404 * benefits from the saved space.
406 * __wait_on_page_locked() and unlock_page() in mm/filemap.c, are the
407 * primary users of these fields, and in mm/page_alloc.c
408 * free_area_init_core() performs the initialization of them.
410 wait_queue_head_t * wait_table;
411 unsigned long wait_table_hash_nr_entries;
412 unsigned long wait_table_bits;
415 * Discontig memory support fields.
417 struct pglist_data *zone_pgdat;
418 /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
419 unsigned long zone_start_pfn;
422 * zone_start_pfn, spanned_pages and present_pages are all
423 * protected by span_seqlock. It is a seqlock because it has
424 * to be read outside of zone->lock, and it is done in the main
425 * allocator path. But, it is written quite infrequently.
427 * The lock is declared along with zone->lock because it is
428 * frequently read in proximity to zone->lock. It's good to
429 * give them a chance of being in the same cacheline.
431 unsigned long spanned_pages; /* total size, including holes */
432 unsigned long present_pages; /* amount of memory (excluding holes) */
435 * rarely used fields:
438 } ____cacheline_internodealigned_in_smp;
441 ZONE_RECLAIM_LOCKED, /* prevents concurrent reclaim */
442 ZONE_OOM_LOCKED, /* zone is in OOM killer zonelist */
443 ZONE_CONGESTED, /* zone has many dirty pages backed by
448 static inline void zone_set_flag(struct zone *zone, zone_flags_t flag)
450 set_bit(flag, &zone->flags);
453 static inline int zone_test_and_set_flag(struct zone *zone, zone_flags_t flag)
455 return test_and_set_bit(flag, &zone->flags);
458 static inline void zone_clear_flag(struct zone *zone, zone_flags_t flag)
460 clear_bit(flag, &zone->flags);
463 static inline int zone_is_reclaim_congested(const struct zone *zone)
465 return test_bit(ZONE_CONGESTED, &zone->flags);
468 static inline int zone_is_reclaim_locked(const struct zone *zone)
470 return test_bit(ZONE_RECLAIM_LOCKED, &zone->flags);
473 static inline int zone_is_oom_locked(const struct zone *zone)
475 return test_bit(ZONE_OOM_LOCKED, &zone->flags);
479 * The "priority" of VM scanning is how much of the queues we will scan in one
480 * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
481 * queues ("queue_length >> 12") during an aging round.
483 #define DEF_PRIORITY 12
485 /* Maximum number of zones on a zonelist */
486 #define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
491 * The NUMA zonelists are doubled because we need zonelists that restrict the
492 * allocations to a single node for GFP_THISNODE.
494 * [0] : Zonelist with fallback
495 * [1] : No fallback (GFP_THISNODE)
497 #define MAX_ZONELISTS 2
501 * We cache key information from each zonelist for smaller cache
502 * footprint when scanning for free pages in get_page_from_freelist().
504 * 1) The BITMAP fullzones tracks which zones in a zonelist have come
505 * up short of free memory since the last time (last_fullzone_zap)
506 * we zero'd fullzones.
507 * 2) The array z_to_n[] maps each zone in the zonelist to its node
508 * id, so that we can efficiently evaluate whether that node is
509 * set in the current tasks mems_allowed.
511 * Both fullzones and z_to_n[] are one-to-one with the zonelist,
512 * indexed by a zones offset in the zonelist zones[] array.
514 * The get_page_from_freelist() routine does two scans. During the
515 * first scan, we skip zones whose corresponding bit in 'fullzones'
516 * is set or whose corresponding node in current->mems_allowed (which
517 * comes from cpusets) is not set. During the second scan, we bypass
518 * this zonelist_cache, to ensure we look methodically at each zone.
520 * Once per second, we zero out (zap) fullzones, forcing us to
521 * reconsider nodes that might have regained more free memory.
522 * The field last_full_zap is the time we last zapped fullzones.
524 * This mechanism reduces the amount of time we waste repeatedly
525 * reexaming zones for free memory when they just came up low on
526 * memory momentarilly ago.
528 * The zonelist_cache struct members logically belong in struct
529 * zonelist. However, the mempolicy zonelists constructed for
530 * MPOL_BIND are intentionally variable length (and usually much
531 * shorter). A general purpose mechanism for handling structs with
532 * multiple variable length members is more mechanism than we want
533 * here. We resort to some special case hackery instead.
535 * The MPOL_BIND zonelists don't need this zonelist_cache (in good
536 * part because they are shorter), so we put the fixed length stuff
537 * at the front of the zonelist struct, ending in a variable length
538 * zones[], as is needed by MPOL_BIND.
540 * Then we put the optional zonelist cache on the end of the zonelist
541 * struct. This optional stuff is found by a 'zlcache_ptr' pointer in
542 * the fixed length portion at the front of the struct. This pointer
543 * both enables us to find the zonelist cache, and in the case of
544 * MPOL_BIND zonelists, (which will just set the zlcache_ptr to NULL)
545 * to know that the zonelist cache is not there.
547 * The end result is that struct zonelists come in two flavors:
548 * 1) The full, fixed length version, shown below, and
549 * 2) The custom zonelists for MPOL_BIND.
550 * The custom MPOL_BIND zonelists have a NULL zlcache_ptr and no zlcache.
552 * Even though there may be multiple CPU cores on a node modifying
553 * fullzones or last_full_zap in the same zonelist_cache at the same
554 * time, we don't lock it. This is just hint data - if it is wrong now
555 * and then, the allocator will still function, perhaps a bit slower.
559 struct zonelist_cache {
560 unsigned short z_to_n[MAX_ZONES_PER_ZONELIST]; /* zone->nid */
561 DECLARE_BITMAP(fullzones, MAX_ZONES_PER_ZONELIST); /* zone full? */
562 unsigned long last_full_zap; /* when last zap'd (jiffies) */
565 #define MAX_ZONELISTS 1
566 struct zonelist_cache;
570 * This struct contains information about a zone in a zonelist. It is stored
571 * here to avoid dereferences into large structures and lookups of tables
574 struct zone *zone; /* Pointer to actual zone */
575 int zone_idx; /* zone_idx(zoneref->zone) */
579 * One allocation request operates on a zonelist. A zonelist
580 * is a list of zones, the first one is the 'goal' of the
581 * allocation, the other zones are fallback zones, in decreasing
584 * If zlcache_ptr is not NULL, then it is just the address of zlcache,
585 * as explained above. If zlcache_ptr is NULL, there is no zlcache.
587 * To speed the reading of the zonelist, the zonerefs contain the zone index
588 * of the entry being read. Helper functions to access information given
589 * a struct zoneref are
591 * zonelist_zone() - Return the struct zone * for an entry in _zonerefs
592 * zonelist_zone_idx() - Return the index of the zone for an entry
593 * zonelist_node_idx() - Return the index of the node for an entry
596 struct zonelist_cache *zlcache_ptr; // NULL or &zlcache
597 struct zoneref _zonerefs[MAX_ZONES_PER_ZONELIST + 1];
599 struct zonelist_cache zlcache; // optional ...
603 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
604 struct node_active_region {
605 unsigned long start_pfn;
606 unsigned long end_pfn;
609 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
611 #ifndef CONFIG_DISCONTIGMEM
612 /* The array of struct pages - for discontigmem use pgdat->lmem_map */
613 extern struct page *mem_map;
617 * The pg_data_t structure is used in machines with CONFIG_DISCONTIGMEM
618 * (mostly NUMA machines?) to denote a higher-level memory zone than the
621 * On NUMA machines, each NUMA node would have a pg_data_t to describe
622 * it's memory layout.
624 * Memory statistics and page replacement data structures are maintained on a
628 typedef struct pglist_data {
629 struct zone node_zones[MAX_NR_ZONES];
630 struct zonelist node_zonelists[MAX_ZONELISTS];
632 #ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */
633 struct page *node_mem_map;
634 #ifdef CONFIG_CGROUP_MEM_RES_CTLR
635 struct page_cgroup *node_page_cgroup;
638 #ifndef CONFIG_NO_BOOTMEM
639 struct bootmem_data *bdata;
641 #ifdef CONFIG_MEMORY_HOTPLUG
643 * Must be held any time you expect node_start_pfn, node_present_pages
644 * or node_spanned_pages stay constant. Holding this will also
645 * guarantee that any pfn_valid() stays that way.
647 * Nests above zone->lock and zone->size_seqlock.
649 spinlock_t node_size_lock;
651 unsigned long node_start_pfn;
652 unsigned long node_present_pages; /* total number of physical pages */
653 unsigned long node_spanned_pages; /* total size of physical page
654 range, including holes */
656 wait_queue_head_t kswapd_wait;
657 struct task_struct *kswapd; /* Protected by lock_memory_hotplug() */
658 int kswapd_max_order;
659 enum zone_type classzone_idx;
662 #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
663 #define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)
664 #ifdef CONFIG_FLAT_NODE_MEM_MAP
665 #define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr))
667 #define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr))
669 #define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr))
671 #define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)
673 #define node_end_pfn(nid) ({\
674 pg_data_t *__pgdat = NODE_DATA(nid);\
675 __pgdat->node_start_pfn + __pgdat->node_spanned_pages;\
678 #include <linux/memory_hotplug.h>
680 extern struct mutex zonelists_mutex;
681 void build_all_zonelists(void *data);
682 void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx);
683 bool zone_watermark_ok(struct zone *z, int order, unsigned long mark,
684 int classzone_idx, int alloc_flags);
685 bool zone_watermark_ok_safe(struct zone *z, int order, unsigned long mark,
686 int classzone_idx, int alloc_flags);
687 enum memmap_context {
691 extern int init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,
693 enum memmap_context context);
695 #ifdef CONFIG_HAVE_MEMORY_PRESENT
696 void memory_present(int nid, unsigned long start, unsigned long end);
698 static inline void memory_present(int nid, unsigned long start, unsigned long end) {}
701 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
702 int local_memory_node(int node_id);
704 static inline int local_memory_node(int node_id) { return node_id; };
707 #ifdef CONFIG_NEED_NODE_MEMMAP_SIZE
708 unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
712 * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
714 #define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
716 static inline int populated_zone(struct zone *zone)
718 return (!!zone->present_pages);
721 extern int movable_zone;
723 static inline int zone_movable_is_highmem(void)
725 #if defined(CONFIG_HIGHMEM) && defined(CONFIG_ARCH_POPULATES_NODE_MAP)
726 return movable_zone == ZONE_HIGHMEM;
732 static inline int is_highmem_idx(enum zone_type idx)
734 #ifdef CONFIG_HIGHMEM
735 return (idx == ZONE_HIGHMEM ||
736 (idx == ZONE_MOVABLE && zone_movable_is_highmem()));
742 static inline int is_normal_idx(enum zone_type idx)
744 return (idx == ZONE_NORMAL);
748 * is_highmem - helper function to quickly check if a struct zone is a
749 * highmem zone or not. This is an attempt to keep references
750 * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
751 * @zone - pointer to struct zone variable
753 static inline int is_highmem(struct zone *zone)
755 #ifdef CONFIG_HIGHMEM
756 int zone_off = (char *)zone - (char *)zone->zone_pgdat->node_zones;
757 return zone_off == ZONE_HIGHMEM * sizeof(*zone) ||
758 (zone_off == ZONE_MOVABLE * sizeof(*zone) &&
759 zone_movable_is_highmem());
765 static inline int is_normal(struct zone *zone)
767 return zone == zone->zone_pgdat->node_zones + ZONE_NORMAL;
770 static inline int is_dma32(struct zone *zone)
772 #ifdef CONFIG_ZONE_DMA32
773 return zone == zone->zone_pgdat->node_zones + ZONE_DMA32;
779 static inline int is_dma(struct zone *zone)
781 #ifdef CONFIG_ZONE_DMA
782 return zone == zone->zone_pgdat->node_zones + ZONE_DMA;
788 /* These two functions are used to setup the per zone pages min values */
790 int min_free_kbytes_sysctl_handler(struct ctl_table *, int,
791 void __user *, size_t *, loff_t *);
792 extern int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1];
793 int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *, int,
794 void __user *, size_t *, loff_t *);
795 int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *, int,
796 void __user *, size_t *, loff_t *);
797 int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *, int,
798 void __user *, size_t *, loff_t *);
799 int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *, int,
800 void __user *, size_t *, loff_t *);
802 extern int numa_zonelist_order_handler(struct ctl_table *, int,
803 void __user *, size_t *, loff_t *);
804 extern char numa_zonelist_order[];
805 #define NUMA_ZONELIST_ORDER_LEN 16 /* string buffer size */
807 #ifndef CONFIG_NEED_MULTIPLE_NODES
809 extern struct pglist_data contig_page_data;
810 #define NODE_DATA(nid) (&contig_page_data)
811 #define NODE_MEM_MAP(nid) mem_map
813 #else /* CONFIG_NEED_MULTIPLE_NODES */
815 #include <asm/mmzone.h>
817 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
819 extern struct pglist_data *first_online_pgdat(void);
820 extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat);
821 extern struct zone *next_zone(struct zone *zone);
824 * for_each_online_pgdat - helper macro to iterate over all online nodes
825 * @pgdat - pointer to a pg_data_t variable
827 #define for_each_online_pgdat(pgdat) \
828 for (pgdat = first_online_pgdat(); \
830 pgdat = next_online_pgdat(pgdat))
832 * for_each_zone - helper macro to iterate over all memory zones
833 * @zone - pointer to struct zone variable
835 * The user only needs to declare the zone variable, for_each_zone
838 #define for_each_zone(zone) \
839 for (zone = (first_online_pgdat())->node_zones; \
841 zone = next_zone(zone))
843 #define for_each_populated_zone(zone) \
844 for (zone = (first_online_pgdat())->node_zones; \
846 zone = next_zone(zone)) \
847 if (!populated_zone(zone)) \
851 static inline struct zone *zonelist_zone(struct zoneref *zoneref)
853 return zoneref->zone;
856 static inline int zonelist_zone_idx(struct zoneref *zoneref)
858 return zoneref->zone_idx;
861 static inline int zonelist_node_idx(struct zoneref *zoneref)
864 /* zone_to_nid not available in this context */
865 return zoneref->zone->node;
868 #endif /* CONFIG_NUMA */
872 * 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
873 * @z - The cursor used as a starting point for the search
874 * @highest_zoneidx - The zone index of the highest zone to return
875 * @nodes - An optional nodemask to filter the zonelist with
876 * @zone - The first suitable zone found is returned via this parameter
878 * This function returns the next zone at or below a given zone index that is
879 * within the allowed nodemask using a cursor as the starting point for the
880 * search. The zoneref returned is a cursor that represents the current zone
881 * being examined. It should be advanced by one before calling
882 * next_zones_zonelist again.
884 struct zoneref *next_zones_zonelist(struct zoneref *z,
885 enum zone_type highest_zoneidx,
890 * first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nodemask in a zonelist
891 * @zonelist - The zonelist to search for a suitable zone
892 * @highest_zoneidx - The zone index of the highest zone to return
893 * @nodes - An optional nodemask to filter the zonelist with
894 * @zone - The first suitable zone found is returned via this parameter
896 * This function returns the first zone at or below a given zone index that is
897 * within the allowed nodemask. The zoneref returned is a cursor that can be
898 * used to iterate the zonelist with next_zones_zonelist by advancing it by
899 * one before calling.
901 static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist,
902 enum zone_type highest_zoneidx,
906 return next_zones_zonelist(zonelist->_zonerefs, highest_zoneidx, nodes,
911 * 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
912 * @zone - The current zone in the iterator
913 * @z - The current pointer within zonelist->zones being iterated
914 * @zlist - The zonelist being iterated
915 * @highidx - The zone index of the highest zone to return
916 * @nodemask - Nodemask allowed by the allocator
918 * This iterator iterates though all zones at or below a given zone index and
919 * within a given nodemask
921 #define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
922 for (z = first_zones_zonelist(zlist, highidx, nodemask, &zone); \
924 z = next_zones_zonelist(++z, highidx, nodemask, &zone)) \
927 * for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index
928 * @zone - The current zone in the iterator
929 * @z - The current pointer within zonelist->zones being iterated
930 * @zlist - The zonelist being iterated
931 * @highidx - The zone index of the highest zone to return
933 * This iterator iterates though all zones at or below a given zone index.
935 #define for_each_zone_zonelist(zone, z, zlist, highidx) \
936 for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)
938 #ifdef CONFIG_SPARSEMEM
939 #include <asm/sparsemem.h>
942 #if !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) && \
943 !defined(CONFIG_ARCH_POPULATES_NODE_MAP)
944 static inline unsigned long early_pfn_to_nid(unsigned long pfn)
950 #ifdef CONFIG_FLATMEM
951 #define pfn_to_nid(pfn) (0)
954 #ifdef CONFIG_SPARSEMEM
957 * SECTION_SHIFT #bits space required to store a section #
959 * PA_SECTION_SHIFT physical address to/from section number
960 * PFN_SECTION_SHIFT pfn to/from section number
962 #define SECTIONS_SHIFT (MAX_PHYSMEM_BITS - SECTION_SIZE_BITS)
964 #define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
965 #define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)
967 #define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
969 #define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)
970 #define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))
972 #define SECTION_BLOCKFLAGS_BITS \
973 ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS)
975 #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
976 #error Allocator MAX_ORDER exceeds SECTION_SIZE
979 #define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
980 #define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
982 #define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)
983 #define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)
989 * This is, logically, a pointer to an array of struct
990 * pages. However, it is stored with some other magic.
991 * (see sparse.c::sparse_init_one_section())
993 * Additionally during early boot we encode node id of
994 * the location of the section here to guide allocation.
995 * (see sparse.c::memory_present())
997 * Making it a UL at least makes someone do a cast
998 * before using it wrong.
1000 unsigned long section_mem_map;
1002 /* See declaration of similar field in struct zone */
1003 unsigned long *pageblock_flags;
1004 #ifdef CONFIG_CGROUP_MEM_RES_CTLR
1006 * If !SPARSEMEM, pgdat doesn't have page_cgroup pointer. We use
1007 * section. (see memcontrol.h/page_cgroup.h about this.)
1009 struct page_cgroup *page_cgroup;
1014 #ifdef CONFIG_SPARSEMEM_EXTREME
1015 #define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))
1017 #define SECTIONS_PER_ROOT 1
1020 #define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
1021 #define NR_SECTION_ROOTS DIV_ROUND_UP(NR_MEM_SECTIONS, SECTIONS_PER_ROOT)
1022 #define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)
1024 #ifdef CONFIG_SPARSEMEM_EXTREME
1025 extern struct mem_section *mem_section[NR_SECTION_ROOTS];
1027 extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
1030 static inline struct mem_section *__nr_to_section(unsigned long nr)
1032 if (!mem_section[SECTION_NR_TO_ROOT(nr)])
1034 return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK];
1036 extern int __section_nr(struct mem_section* ms);
1037 extern unsigned long usemap_size(void);
1040 * We use the lower bits of the mem_map pointer to store
1041 * a little bit of information. There should be at least
1042 * 3 bits here due to 32-bit alignment.
1044 #define SECTION_MARKED_PRESENT (1UL<<0)
1045 #define SECTION_HAS_MEM_MAP (1UL<<1)
1046 #define SECTION_MAP_LAST_BIT (1UL<<2)
1047 #define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1))
1048 #define SECTION_NID_SHIFT 2
1050 static inline struct page *__section_mem_map_addr(struct mem_section *section)
1052 unsigned long map = section->section_mem_map;
1053 map &= SECTION_MAP_MASK;
1054 return (struct page *)map;
1057 static inline int present_section(struct mem_section *section)
1059 return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));
1062 static inline int present_section_nr(unsigned long nr)
1064 return present_section(__nr_to_section(nr));
1067 static inline int valid_section(struct mem_section *section)
1069 return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));
1072 static inline int valid_section_nr(unsigned long nr)
1074 return valid_section(__nr_to_section(nr));
1077 static inline struct mem_section *__pfn_to_section(unsigned long pfn)
1079 return __nr_to_section(pfn_to_section_nr(pfn));
1082 #ifndef CONFIG_HAVE_ARCH_PFN_VALID
1083 static inline int pfn_valid(unsigned long pfn)
1085 if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
1087 return valid_section(__nr_to_section(pfn_to_section_nr(pfn)));
1091 static inline int pfn_present(unsigned long pfn)
1093 if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
1095 return present_section(__nr_to_section(pfn_to_section_nr(pfn)));
1099 * These are _only_ used during initialisation, therefore they
1100 * can use __initdata ... They could have names to indicate
1104 #define pfn_to_nid(pfn) \
1106 unsigned long __pfn_to_nid_pfn = (pfn); \
1107 page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \
1110 #define pfn_to_nid(pfn) (0)
1113 #define early_pfn_valid(pfn) pfn_valid(pfn)
1114 void sparse_init(void);
1116 #define sparse_init() do {} while (0)
1117 #define sparse_index_init(_sec, _nid) do {} while (0)
1118 #endif /* CONFIG_SPARSEMEM */
1120 #ifdef CONFIG_NODES_SPAN_OTHER_NODES
1121 bool early_pfn_in_nid(unsigned long pfn, int nid);
1123 #define early_pfn_in_nid(pfn, nid) (1)
1126 #ifndef early_pfn_valid
1127 #define early_pfn_valid(pfn) (1)
1130 void memory_present(int nid, unsigned long start, unsigned long end);
1131 unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
1134 * If it is possible to have holes within a MAX_ORDER_NR_PAGES, then we
1135 * need to check pfn validility within that MAX_ORDER_NR_PAGES block.
1136 * pfn_valid_within() should be used in this case; we optimise this away
1137 * when we have no holes within a MAX_ORDER_NR_PAGES block.
1139 #ifdef CONFIG_HOLES_IN_ZONE
1140 #define pfn_valid_within(pfn) pfn_valid(pfn)
1142 #define pfn_valid_within(pfn) (1)
1145 #ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
1147 * pfn_valid() is meant to be able to tell if a given PFN has valid memmap
1148 * associated with it or not. In FLATMEM, it is expected that holes always
1149 * have valid memmap as long as there is valid PFNs either side of the hole.
1150 * In SPARSEMEM, it is assumed that a valid section has a memmap for the
1153 * However, an ARM, and maybe other embedded architectures in the future
1154 * free memmap backing holes to save memory on the assumption the memmap is
1155 * never used. The page_zone linkages are then broken even though pfn_valid()
1156 * returns true. A walker of the full memmap must then do this additional
1157 * check to ensure the memmap they are looking at is sane by making sure
1158 * the zone and PFN linkages are still valid. This is expensive, but walkers
1159 * of the full memmap are extremely rare.
1161 int memmap_valid_within(unsigned long pfn,
1162 struct page *page, struct zone *zone);
1164 static inline int memmap_valid_within(unsigned long pfn,
1165 struct page *page, struct zone *zone)
1169 #endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
1171 #endif /* !__GENERATING_BOUNDS.H */
1172 #endif /* !__ASSEMBLY__ */
1173 #endif /* _LINUX_MMZONE_H */