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
27 struct free_area {
28 struct list_head free_list;
29 unsigned long nr_free;
30 };
31
32 struct 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)
41 struct 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
49 enum 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
70 struct 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
77 struct 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
139 struct 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 */
288 struct 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 */
304 struct bootmem_data;
305 typedef 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
344 void __get_zone_counts(unsigned long *active, unsigned long *inactive,
345 unsigned long *free, struct pglist_data *pgdat);
346 void get_zone_counts(unsigned long *active, unsigned long *inactive,
347 unsigned long *free);
348 void build_all_zonelists(void);
349 void wakeup_kswapd(struct zone *zone, int order);
350 int zone_watermark_ok(struct zone *z, int order, unsigned long mark,
351 int classzone_idx, int alloc_flags);
352
353 extern int init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,
354 unsigned long size);
355
356 #ifdef CONFIG_HAVE_MEMORY_PRESENT
357 void memory_present(int nid, unsigned long start, unsigned long end);
358 #else
memory_present(int nid,unsigned long start,unsigned long end)359 static inline void memory_present(int nid, unsigned long start, unsigned long end) {}
360 #endif
361
362 #ifdef CONFIG_NEED_NODE_MEMMAP_SIZE
363 unsigned 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
populated_zone(struct zone * zone)371 static inline int populated_zone(struct zone *zone)
372 {
373 return (!!zone->present_pages);
374 }
375
is_highmem_idx(int idx)376 static inline int is_highmem_idx(int idx)
377 {
378 return (idx == ZONE_HIGHMEM);
379 }
380
is_normal_idx(int idx)381 static 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 */
is_highmem(struct zone * zone)392 static inline int is_highmem(struct zone *zone)
393 {
394 return zone == zone->zone_pgdat->node_zones + ZONE_HIGHMEM;
395 }
396
is_normal(struct zone * zone)397 static inline int is_normal(struct zone *zone)
398 {
399 return zone == zone->zone_pgdat->node_zones + ZONE_NORMAL;
400 }
401
is_dma32(struct zone * zone)402 static inline int is_dma32(struct zone *zone)
403 {
404 return zone == zone->zone_pgdat->node_zones + ZONE_DMA32;
405 }
406
is_dma(struct zone * zone)407 static 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 */
413 struct ctl_table;
414 struct file;
415 int min_free_kbytes_sysctl_handler(struct ctl_table *, int, struct file *,
416 void __user *, size_t *, loff_t *);
417 extern int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1];
418 int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *, int, struct file *,
419 void __user *, size_t *, loff_t *);
420 int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *, int, struct file *,
421 void __user *, size_t *, loff_t *);
422 int 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
433 extern 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
444 extern struct pglist_data *first_online_pgdat(void);
445 extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat);
446 extern 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
524 struct page;
525 struct 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
552 extern struct mem_section *mem_section[NR_SECTION_ROOTS];
553 #else
554 extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
555 #endif
556
__nr_to_section(unsigned long nr)557 static 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 }
563 extern 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
__section_mem_map_addr(struct mem_section * section)576 static 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
valid_section(struct mem_section * section)583 static inline int valid_section(struct mem_section *section)
584 {
585 return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));
586 }
587
section_has_mem_map(struct mem_section * section)588 static inline int section_has_mem_map(struct mem_section *section)
589 {
590 return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));
591 }
592
valid_section_nr(unsigned long nr)593 static inline int valid_section_nr(unsigned long nr)
594 {
595 return valid_section(__nr_to_section(nr));
596 }
597
__pfn_to_section(unsigned long pfn)598 static inline struct mem_section *__pfn_to_section(unsigned long pfn)
599 {
600 return __nr_to_section(pfn_to_section_nr(pfn));
601 }
602
pfn_valid(unsigned long pfn)603 static 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)
626 void 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
636 void memory_present(int nid, unsigned long start, unsigned long end);
637 unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
638
639 #endif /* !__ASSEMBLY__ */
640 #endif /* __KERNEL__ */
641 #endif /* _LINUX_MMZONE_H */
642