1#ifndef _LINUX_MMZONE_H
2#define _LINUX_MMZONE_H
3
4#ifdef __KERNEL__
5#ifndef __ASSEMBLY__
6
7#include <linux/spinlock.h>
8#include <linux/list.h>
9#include <linux/wait.h>
10#include <linux/cache.h>
11#include <linux/threads.h>
12#include <linux/numa.h>
13#include <linux/init.h>
14#include <linux/seqlock.h>
15#include <linux/nodemask.h>
16#include <asm/atomic.h>
17#include <asm/page.h>
18
19/* Free memory management - zoned buddy allocator.  */
20#ifndef CONFIG_FORCE_MAX_ZONEORDER
21#define MAX_ORDER 11
22#else
23#define MAX_ORDER CONFIG_FORCE_MAX_ZONEORDER
24#endif
25#define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1))
26
27struct free_area {
28	struct list_head	free_list;
29	unsigned long		nr_free;
30};
31
32struct pglist_data;
33
34/*
35 * zone->lock and zone->lru_lock are two of the hottest locks in the kernel.
36 * So add a wild amount of padding here to ensure that they fall into separate
37 * cachelines.  There are very few zone structures in the machine, so space
38 * consumption is not a concern here.
39 */
40#if defined(CONFIG_SMP)
41struct zone_padding {
42	char x[0];
43} ____cacheline_internodealigned_in_smp;
44#define ZONE_PADDING(name)	struct zone_padding name;
45#else
46#define ZONE_PADDING(name)
47#endif
48
49enum zone_stat_item {
50	NR_ANON_PAGES,	/* Mapped anonymous pages */
51	NR_FILE_MAPPED,	/* pagecache pages mapped into pagetables.
52			   only modified from process context */
53	NR_FILE_PAGES,
54	NR_SLAB,	/* Pages used by slab allocator */
55	NR_PAGETABLE,	/* used for pagetables */
56	NR_FILE_DIRTY,
57	NR_WRITEBACK,
58	NR_UNSTABLE_NFS,	/* NFS unstable pages */
59	NR_BOUNCE,
60#ifdef CONFIG_NUMA
61	NUMA_HIT,		/* allocated in intended node */
62	NUMA_MISS,		/* allocated in non intended node */
63	NUMA_FOREIGN,		/* was intended here, hit elsewhere */
64	NUMA_INTERLEAVE_HIT,	/* interleaver preferred this zone */
65	NUMA_LOCAL,		/* allocation from local node */
66	NUMA_OTHER,		/* allocation from other node */
67#endif
68	NR_VM_ZONE_STAT_ITEMS };
69
70struct per_cpu_pages {
71	int count;		/* number of pages in the list */
72	int high;		/* high watermark, emptying needed */
73	int batch;		/* chunk size for buddy add/remove */
74	struct list_head list;	/* the list of pages */
75};
76
77struct per_cpu_pageset {
78	struct per_cpu_pages pcp[2];	/* 0: hot.  1: cold */
79#ifdef CONFIG_SMP
80	s8 stat_threshold;
81	s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS];
82#endif
83} ____cacheline_aligned_in_smp;
84
85#ifdef CONFIG_NUMA
86#define zone_pcp(__z, __cpu) ((__z)->pageset[(__cpu)])
87#else
88#define zone_pcp(__z, __cpu) (&(__z)->pageset[(__cpu)])
89#endif
90
91#define ZONE_DMA		0
92#define ZONE_DMA32		1
93#define ZONE_NORMAL		2
94#define ZONE_HIGHMEM		3
95
96#define MAX_NR_ZONES		4	/* Sync this with ZONES_SHIFT */
97#define ZONES_SHIFT		2	/* ceil(log2(MAX_NR_ZONES)) */
98
99
100/*
101 * When a memory allocation must conform to specific limitations (such
102 * as being suitable for DMA) the caller will pass in hints to the
103 * allocator in the gfp_mask, in the zone modifier bits.  These bits
104 * are used to select a priority ordered list of memory zones which
105 * match the requested limits.  GFP_ZONEMASK defines which bits within
106 * the gfp_mask should be considered as zone modifiers.  Each valid
107 * combination of the zone modifier bits has a corresponding list
108 * of zones (in node_zonelists).  Thus for two zone modifiers there
109 * will be a maximum of 4 (2 ** 2) zonelists, for 3 modifiers there will
110 * be 8 (2 ** 3) zonelists.  GFP_ZONETYPES defines the number of possible
111 * combinations of zone modifiers in "zone modifier space".
112 *
113 * As an optimisation any zone modifier bits which are only valid when
114 * no other zone modifier bits are set (loners) should be placed in
115 * the highest order bits of this field.  This allows us to reduce the
116 * extent of the zonelists thus saving space.  For example in the case
117 * of three zone modifier bits, we could require up to eight zonelists.
118 * If the left most zone modifier is a "loner" then the highest valid
119 * zonelist would be four allowing us to allocate only five zonelists.
120 * Use the first form for GFP_ZONETYPES when the left most bit is not
121 * a "loner", otherwise use the second.
122 *
123 * NOTE! Make sure this matches the zones in <linux/gfp.h>
124 */
125#define GFP_ZONEMASK	0x07
126/* #define GFP_ZONETYPES       (GFP_ZONEMASK + 1) */           /* Non-loner */
127#define GFP_ZONETYPES  ((GFP_ZONEMASK + 1) / 2 + 1)            /* Loner */
128
129/*
130 * On machines where it is needed (eg PCs) we divide physical memory
131 * into multiple physical zones. On a 32bit PC we have 4 zones:
132 *
133 * ZONE_DMA	  < 16 MB	ISA DMA capable memory
134 * ZONE_DMA32	     0 MB 	Empty
135 * ZONE_NORMAL	16-896 MB	direct mapped by the kernel
136 * ZONE_HIGHMEM	 > 896 MB	only page cache and user processes
137 */
138
139struct zone {
140	/* Fields commonly accessed by the page allocator */
141	unsigned long		free_pages;
142	unsigned long		pages_min, pages_low, pages_high;
143	/*
144	 * We don't know if the memory that we're going to allocate will be freeable
145	 * or/and it will be released eventually, so to avoid totally wasting several
146	 * GB of ram we must reserve some of the lower zone memory (otherwise we risk
147	 * to run OOM on the lower zones despite there's tons of freeable ram
148	 * on the higher zones). This array is recalculated at runtime if the
149	 * sysctl_lowmem_reserve_ratio sysctl changes.
150	 */
151	unsigned long		lowmem_reserve[MAX_NR_ZONES];
152
153#ifdef CONFIG_NUMA
154	/*
155	 * zone reclaim becomes active if more unmapped pages exist.
156	 */
157	unsigned long		min_unmapped_ratio;
158	struct per_cpu_pageset	*pageset[NR_CPUS];
159#else
160	struct per_cpu_pageset	pageset[NR_CPUS];
161#endif
162	/*
163	 * free areas of different sizes
164	 */
165	spinlock_t		lock;
166#ifdef CONFIG_MEMORY_HOTPLUG
167	/* see spanned/present_pages for more description */
168	seqlock_t		span_seqlock;
169#endif
170	struct free_area	free_area[MAX_ORDER];
171
172
173	ZONE_PADDING(_pad1_)
174
175	/* Fields commonly accessed by the page reclaim scanner */
176	spinlock_t		lru_lock;
177	struct list_head	active_list;
178	struct list_head	inactive_list;
179	unsigned long		nr_scan_active;
180	unsigned long		nr_scan_inactive;
181	unsigned long		nr_active;
182	unsigned long		nr_inactive;
183	unsigned long		pages_scanned;	   /* since last reclaim */
184	int			all_unreclaimable; /* All pages pinned */
185
186	/* A count of how many reclaimers are scanning this zone */
187	atomic_t		reclaim_in_progress;
188
189	/* Zone statistics */
190	atomic_long_t		vm_stat[NR_VM_ZONE_STAT_ITEMS];
191
192	/*
193	 * prev_priority holds the scanning priority for this zone.  It is
194	 * defined as the scanning priority at which we achieved our reclaim
195	 * target at the previous try_to_free_pages() or balance_pgdat()
196	 * invokation.
197	 *
198	 * We use prev_priority as a measure of how much stress page reclaim is
199	 * under - it drives the swappiness decision: whether to unmap mapped
200	 * pages.
201	 *
202	 * temp_priority is used to remember the scanning priority at which
203	 * this zone was successfully refilled to free_pages == pages_high.
204	 *
205	 * Access to both these fields is quite racy even on uniprocessor.  But
206	 * it is expected to average out OK.
207	 */
208	int temp_priority;
209	int prev_priority;
210
211
212	ZONE_PADDING(_pad2_)
213	/* Rarely used or read-mostly fields */
214
215	/*
216	 * wait_table		-- the array holding the hash table
217	 * wait_table_hash_nr_entries	-- the size of the hash table array
218	 * wait_table_bits	-- wait_table_size == (1 << wait_table_bits)
219	 *
220	 * The purpose of all these is to keep track of the people
221	 * waiting for a page to become available and make them
222	 * runnable again when possible. The trouble is that this
223	 * consumes a lot of space, especially when so few things
224	 * wait on pages at a given time. So instead of using
225	 * per-page waitqueues, we use a waitqueue hash table.
226	 *
227	 * The bucket discipline is to sleep on the same queue when
228	 * colliding and wake all in that wait queue when removing.
229	 * When something wakes, it must check to be sure its page is
230	 * truly available, a la thundering herd. The cost of a
231	 * collision is great, but given the expected load of the
232	 * table, they should be so rare as to be outweighed by the
233	 * benefits from the saved space.
234	 *
235	 * __wait_on_page_locked() and unlock_page() in mm/filemap.c, are the
236	 * primary users of these fields, and in mm/page_alloc.c
237	 * free_area_init_core() performs the initialization of them.
238	 */
239	wait_queue_head_t	* wait_table;
240	unsigned long		wait_table_hash_nr_entries;
241	unsigned long		wait_table_bits;
242
243	/*
244	 * Discontig memory support fields.
245	 */
246	struct pglist_data	*zone_pgdat;
247	/* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
248	unsigned long		zone_start_pfn;
249
250	/*
251	 * zone_start_pfn, spanned_pages and present_pages are all
252	 * protected by span_seqlock.  It is a seqlock because it has
253	 * to be read outside of zone->lock, and it is done in the main
254	 * allocator path.  But, it is written quite infrequently.
255	 *
256	 * The lock is declared along with zone->lock because it is
257	 * frequently read in proximity to zone->lock.  It's good to
258	 * give them a chance of being in the same cacheline.
259	 */
260	unsigned long		spanned_pages;	/* total size, including holes */
261	unsigned long		present_pages;	/* amount of memory (excluding holes) */
262
263	/*
264	 * rarely used fields:
265	 */
266	char			*name;
267} ____cacheline_internodealigned_in_smp;
268
269
270/*
271 * The "priority" of VM scanning is how much of the queues we will scan in one
272 * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
273 * queues ("queue_length >> 12") during an aging round.
274 */
275#define DEF_PRIORITY 12
276
277/*
278 * One allocation request operates on a zonelist. A zonelist
279 * is a list of zones, the first one is the 'goal' of the
280 * allocation, the other zones are fallback zones, in decreasing
281 * priority.
282 *
283 * Right now a zonelist takes up less than a cacheline. We never
284 * modify it apart from boot-up, and only a few indices are used,
285 * so despite the zonelist table being relatively big, the cache
286 * footprint of this construct is very small.
287 */
288struct zonelist {
289	struct zone *zones[MAX_NUMNODES * MAX_NR_ZONES + 1]; // NULL delimited
290};
291
292
293/*
294 * The pg_data_t structure is used in machines with CONFIG_DISCONTIGMEM
295 * (mostly NUMA machines?) to denote a higher-level memory zone than the
296 * zone denotes.
297 *
298 * On NUMA machines, each NUMA node would have a pg_data_t to describe
299 * it's memory layout.
300 *
301 * Memory statistics and page replacement data structures are maintained on a
302 * per-zone basis.
303 */
304struct bootmem_data;
305typedef struct pglist_data {
306	struct zone node_zones[MAX_NR_ZONES];
307	struct zonelist node_zonelists[GFP_ZONETYPES];
308	int nr_zones;
309#ifdef CONFIG_FLAT_NODE_MEM_MAP
310	struct page *node_mem_map;
311#endif
312	struct bootmem_data *bdata;
313#ifdef CONFIG_MEMORY_HOTPLUG
314	/*
315	 * Must be held any time you expect node_start_pfn, node_present_pages
316	 * or node_spanned_pages stay constant.  Holding this will also
317	 * guarantee that any pfn_valid() stays that way.
318	 *
319	 * Nests above zone->lock and zone->size_seqlock.
320	 */
321	spinlock_t node_size_lock;
322#endif
323	unsigned long node_start_pfn;
324	unsigned long node_present_pages; /* total number of physical pages */
325	unsigned long node_spanned_pages; /* total size of physical page
326					     range, including holes */
327	int node_id;
328	wait_queue_head_t kswapd_wait;
329	struct task_struct *kswapd;
330	int kswapd_max_order;
331} pg_data_t;
332
333#define node_present_pages(nid)	(NODE_DATA(nid)->node_present_pages)
334#define node_spanned_pages(nid)	(NODE_DATA(nid)->node_spanned_pages)
335#ifdef CONFIG_FLAT_NODE_MEM_MAP
336#define pgdat_page_nr(pgdat, pagenr)	((pgdat)->node_mem_map + (pagenr))
337#else
338#define pgdat_page_nr(pgdat, pagenr)	pfn_to_page((pgdat)->node_start_pfn + (pagenr))
339#endif
340#define nid_page_nr(nid, pagenr) 	pgdat_page_nr(NODE_DATA(nid),(pagenr))
341
342#include <linux/memory_hotplug.h>
343
344void __get_zone_counts(unsigned long *active, unsigned long *inactive,
345			unsigned long *free, struct pglist_data *pgdat);
346void get_zone_counts(unsigned long *active, unsigned long *inactive,
347			unsigned long *free);
348void build_all_zonelists(void);
349void wakeup_kswapd(struct zone *zone, int order);
350int zone_watermark_ok(struct zone *z, int order, unsigned long mark,
351		int classzone_idx, int alloc_flags);
352
353extern int init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,
354				     unsigned long size);
355
356#ifdef CONFIG_HAVE_MEMORY_PRESENT
357void memory_present(int nid, unsigned long start, unsigned long end);
358#else
359static inline void memory_present(int nid, unsigned long start, unsigned long end) {}
360#endif
361
362#ifdef CONFIG_NEED_NODE_MEMMAP_SIZE
363unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
364#endif
365
366/*
367 * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
368 */
369#define zone_idx(zone)		((zone) - (zone)->zone_pgdat->node_zones)
370
371static inline int populated_zone(struct zone *zone)
372{
373	return (!!zone->present_pages);
374}
375
376static inline int is_highmem_idx(int idx)
377{
378	return (idx == ZONE_HIGHMEM);
379}
380
381static inline int is_normal_idx(int idx)
382{
383	return (idx == ZONE_NORMAL);
384}
385
386/**
387 * is_highmem - helper function to quickly check if a struct zone is a
388 *              highmem zone or not.  This is an attempt to keep references
389 *              to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
390 * @zone - pointer to struct zone variable
391 */
392static inline int is_highmem(struct zone *zone)
393{
394	return zone == zone->zone_pgdat->node_zones + ZONE_HIGHMEM;
395}
396
397static inline int is_normal(struct zone *zone)
398{
399	return zone == zone->zone_pgdat->node_zones + ZONE_NORMAL;
400}
401
402static inline int is_dma32(struct zone *zone)
403{
404	return zone == zone->zone_pgdat->node_zones + ZONE_DMA32;
405}
406
407static inline int is_dma(struct zone *zone)
408{
409	return zone == zone->zone_pgdat->node_zones + ZONE_DMA;
410}
411
412/* These two functions are used to setup the per zone pages min values */
413struct ctl_table;
414struct file;
415int min_free_kbytes_sysctl_handler(struct ctl_table *, int, struct file *,
416					void __user *, size_t *, loff_t *);
417extern int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1];
418int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *, int, struct file *,
419					void __user *, size_t *, loff_t *);
420int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *, int, struct file *,
421					void __user *, size_t *, loff_t *);
422int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *, int,
423			struct file *, void __user *, size_t *, loff_t *);
424
425#include <linux/topology.h>
426/* Returns the number of the current Node. */
427#ifndef numa_node_id
428#define numa_node_id()		(cpu_to_node(raw_smp_processor_id()))
429#endif
430
431#ifndef CONFIG_NEED_MULTIPLE_NODES
432
433extern struct pglist_data contig_page_data;
434#define NODE_DATA(nid)		(&contig_page_data)
435#define NODE_MEM_MAP(nid)	mem_map
436#define MAX_NODES_SHIFT		1
437
438#else /* CONFIG_NEED_MULTIPLE_NODES */
439
440#include <asm/mmzone.h>
441
442#endif /* !CONFIG_NEED_MULTIPLE_NODES */
443
444extern struct pglist_data *first_online_pgdat(void);
445extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat);
446extern struct zone *next_zone(struct zone *zone);
447
448/**
449 * for_each_pgdat - helper macro to iterate over all nodes
450 * @pgdat - pointer to a pg_data_t variable
451 */
452#define for_each_online_pgdat(pgdat)			\
453	for (pgdat = first_online_pgdat();		\
454	     pgdat;					\
455	     pgdat = next_online_pgdat(pgdat))
456/**
457 * for_each_zone - helper macro to iterate over all memory zones
458 * @zone - pointer to struct zone variable
459 *
460 * The user only needs to declare the zone variable, for_each_zone
461 * fills it in.
462 */
463#define for_each_zone(zone)			        \
464	for (zone = (first_online_pgdat())->node_zones; \
465	     zone;					\
466	     zone = next_zone(zone))
467
468#ifdef CONFIG_SPARSEMEM
469#include <asm/sparsemem.h>
470#endif
471
472#if BITS_PER_LONG == 32
473/*
474 * with 32 bit page->flags field, we reserve 9 bits for node/zone info.
475 * there are 4 zones (3 bits) and this leaves 9-3=6 bits for nodes.
476 */
477#define FLAGS_RESERVED		9
478
479#elif BITS_PER_LONG == 64
480/*
481 * with 64 bit flags field, there's plenty of room.
482 */
483#define FLAGS_RESERVED		32
484
485#else
486
487#error BITS_PER_LONG not defined
488
489#endif
490
491#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
492#define early_pfn_to_nid(nid)  (0UL)
493#endif
494
495#ifdef CONFIG_FLATMEM
496#define pfn_to_nid(pfn)		(0)
497#endif
498
499#define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
500#define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
501
502#ifdef CONFIG_SPARSEMEM
503
504/*
505 * SECTION_SHIFT    		#bits space required to store a section #
506 *
507 * PA_SECTION_SHIFT		physical address to/from section number
508 * PFN_SECTION_SHIFT		pfn to/from section number
509 */
510#define SECTIONS_SHIFT		(MAX_PHYSMEM_BITS - SECTION_SIZE_BITS)
511
512#define PA_SECTION_SHIFT	(SECTION_SIZE_BITS)
513#define PFN_SECTION_SHIFT	(SECTION_SIZE_BITS - PAGE_SHIFT)
514
515#define NR_MEM_SECTIONS		(1UL << SECTIONS_SHIFT)
516
517#define PAGES_PER_SECTION       (1UL << PFN_SECTION_SHIFT)
518#define PAGE_SECTION_MASK	(~(PAGES_PER_SECTION-1))
519
520#if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
521#error Allocator MAX_ORDER exceeds SECTION_SIZE
522#endif
523
524struct page;
525struct mem_section {
526	/*
527	 * This is, logically, a pointer to an array of struct
528	 * pages.  However, it is stored with some other magic.
529	 * (see sparse.c::sparse_init_one_section())
530	 *
531	 * Additionally during early boot we encode node id of
532	 * the location of the section here to guide allocation.
533	 * (see sparse.c::memory_present())
534	 *
535	 * Making it a UL at least makes someone do a cast
536	 * before using it wrong.
537	 */
538	unsigned long section_mem_map;
539};
540
541#ifdef CONFIG_SPARSEMEM_EXTREME
542#define SECTIONS_PER_ROOT       (PAGE_SIZE / sizeof (struct mem_section))
543#else
544#define SECTIONS_PER_ROOT	1
545#endif
546
547#define SECTION_NR_TO_ROOT(sec)	((sec) / SECTIONS_PER_ROOT)
548#define NR_SECTION_ROOTS	(NR_MEM_SECTIONS / SECTIONS_PER_ROOT)
549#define SECTION_ROOT_MASK	(SECTIONS_PER_ROOT - 1)
550
551#ifdef CONFIG_SPARSEMEM_EXTREME
552extern struct mem_section *mem_section[NR_SECTION_ROOTS];
553#else
554extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
555#endif
556
557static inline struct mem_section *__nr_to_section(unsigned long nr)
558{
559	if (!mem_section[SECTION_NR_TO_ROOT(nr)])
560		return NULL;
561	return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK];
562}
563extern int __section_nr(struct mem_section* ms);
564
565/*
566 * We use the lower bits of the mem_map pointer to store
567 * a little bit of information.  There should be at least
568 * 3 bits here due to 32-bit alignment.
569 */
570#define	SECTION_MARKED_PRESENT	(1UL<<0)
571#define SECTION_HAS_MEM_MAP	(1UL<<1)
572#define SECTION_MAP_LAST_BIT	(1UL<<2)
573#define SECTION_MAP_MASK	(~(SECTION_MAP_LAST_BIT-1))
574#define SECTION_NID_SHIFT	2
575
576static inline struct page *__section_mem_map_addr(struct mem_section *section)
577{
578	unsigned long map = section->section_mem_map;
579	map &= SECTION_MAP_MASK;
580	return (struct page *)map;
581}
582
583static inline int valid_section(struct mem_section *section)
584{
585	return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));
586}
587
588static inline int section_has_mem_map(struct mem_section *section)
589{
590	return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));
591}
592
593static inline int valid_section_nr(unsigned long nr)
594{
595	return valid_section(__nr_to_section(nr));
596}
597
598static inline struct mem_section *__pfn_to_section(unsigned long pfn)
599{
600	return __nr_to_section(pfn_to_section_nr(pfn));
601}
602
603static inline int pfn_valid(unsigned long pfn)
604{
605	if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
606		return 0;
607	return valid_section(__nr_to_section(pfn_to_section_nr(pfn)));
608}
609
610/*
611 * These are _only_ used during initialisation, therefore they
612 * can use __initdata ...  They could have names to indicate
613 * this restriction.
614 */
615#ifdef CONFIG_NUMA
616#define pfn_to_nid(pfn)							\
617({									\
618	unsigned long __pfn_to_nid_pfn = (pfn);				\
619	page_to_nid(pfn_to_page(__pfn_to_nid_pfn));			\
620})
621#else
622#define pfn_to_nid(pfn)		(0)
623#endif
624
625#define early_pfn_valid(pfn)	pfn_valid(pfn)
626void sparse_init(void);
627#else
628#define sparse_init()	do {} while (0)
629#define sparse_index_init(_sec, _nid)  do {} while (0)
630#endif /* CONFIG_SPARSEMEM */
631
632#ifndef early_pfn_valid
633#define early_pfn_valid(pfn)	(1)
634#endif
635
636void memory_present(int nid, unsigned long start, unsigned long end);
637unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
638
639#endif /* !__ASSEMBLY__ */
640#endif /* __KERNEL__ */
641#endif /* _LINUX_MMZONE_H */
642