1 #ifndef _LINUX_MMZONE_H
2 #define _LINUX_MMZONE_H
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>
19 /* Free memory management - zoned buddy allocator. */
20 #ifndef CONFIG_FORCE_MAX_ZONEORDER
23 #define MAX_ORDER CONFIG_FORCE_MAX_ZONEORDER
25 #define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1))
28 struct list_head free_list;
29 unsigned long nr_free;
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.
40 #if defined(CONFIG_SMP)
43 } ____cacheline_internodealigned_in_smp;
44 #define ZONE_PADDING(name) struct zone_padding name;
46 #define ZONE_PADDING(name)
50 /* First 128 byte cacheline (assuming 64 bit words) */
54 NR_ANON_PAGES, /* Mapped anonymous pages */
55 NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
56 only modified from process context */
60 /* Second 128 byte cacheline */
62 NR_SLAB_UNRECLAIMABLE,
63 NR_PAGETABLE, /* used for pagetables */
64 NR_UNSTABLE_NFS, /* NFS unstable pages */
68 NUMA_HIT, /* allocated in intended node */
69 NUMA_MISS, /* allocated in non intended node */
70 NUMA_FOREIGN, /* was intended here, hit elsewhere */
71 NUMA_INTERLEAVE_HIT, /* interleaver preferred this zone */
72 NUMA_LOCAL, /* allocation from local node */
73 NUMA_OTHER, /* allocation from other node */
75 NR_VM_ZONE_STAT_ITEMS };
77 struct per_cpu_pages {
78 int count; /* number of pages in the list */
79 int high; /* high watermark, emptying needed */
80 int batch; /* chunk size for buddy add/remove */
81 struct list_head list; /* the list of pages */
84 struct per_cpu_pageset {
85 struct per_cpu_pages pcp[2]; /* 0: hot. 1: cold */
91 s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS];
93 } ____cacheline_aligned_in_smp;
96 #define zone_pcp(__z, __cpu) ((__z)->pageset[(__cpu)])
98 #define zone_pcp(__z, __cpu) (&(__z)->pageset[(__cpu)])
102 #ifdef CONFIG_ZONE_DMA
104 * ZONE_DMA is used when there are devices that are not able
105 * to do DMA to all of addressable memory (ZONE_NORMAL). Then we
106 * carve out the portion of memory that is needed for these devices.
107 * The range is arch specific.
112 * ---------------------------
113 * parisc, ia64, sparc <4G
117 * alpha Unlimited or 0-16MB.
119 * i386, x86_64 and multiple other arches
124 #ifdef CONFIG_ZONE_DMA32
126 * x86_64 needs two ZONE_DMAs because it supports devices that are
127 * only able to do DMA to the lower 16M but also 32 bit devices that
128 * can only do DMA areas below 4G.
133 * Normal addressable memory is in ZONE_NORMAL. DMA operations can be
134 * performed on pages in ZONE_NORMAL if the DMA devices support
135 * transfers to all addressable memory.
138 #ifdef CONFIG_HIGHMEM
140 * A memory area that is only addressable by the kernel through
141 * mapping portions into its own address space. This is for example
142 * used by i386 to allow the kernel to address the memory beyond
143 * 900MB. The kernel will set up special mappings (page
144 * table entries on i386) for each page that the kernel needs to
154 * When a memory allocation must conform to specific limitations (such
155 * as being suitable for DMA) the caller will pass in hints to the
156 * allocator in the gfp_mask, in the zone modifier bits. These bits
157 * are used to select a priority ordered list of memory zones which
158 * match the requested limits. See gfp_zone() in include/linux/gfp.h
162 * Count the active zones. Note that the use of defined(X) outside
163 * #if and family is not necessarily defined so ensure we cannot use
164 * it later. Use __ZONE_COUNT to work out how many shift bits we need.
166 #define __ZONE_COUNT ( \
167 defined(CONFIG_ZONE_DMA) \
168 + defined(CONFIG_ZONE_DMA32) \
170 + defined(CONFIG_HIGHMEM) \
174 #define ZONES_SHIFT 0
175 #elif __ZONE_COUNT <= 2
176 #define ZONES_SHIFT 1
177 #elif __ZONE_COUNT <= 4
178 #define ZONES_SHIFT 2
180 #error ZONES_SHIFT -- too many zones configured adjust calculation
185 /* Fields commonly accessed by the page allocator */
186 unsigned long pages_min, pages_low, pages_high;
188 * We don't know if the memory that we're going to allocate will be freeable
189 * or/and it will be released eventually, so to avoid totally wasting several
190 * GB of ram we must reserve some of the lower zone memory (otherwise we risk
191 * to run OOM on the lower zones despite there's tons of freeable ram
192 * on the higher zones). This array is recalculated at runtime if the
193 * sysctl_lowmem_reserve_ratio sysctl changes.
195 unsigned long lowmem_reserve[MAX_NR_ZONES];
200 * zone reclaim becomes active if more unmapped pages exist.
202 unsigned long min_unmapped_pages;
203 unsigned long min_slab_pages;
204 struct per_cpu_pageset *pageset[NR_CPUS];
206 struct per_cpu_pageset pageset[NR_CPUS];
209 * free areas of different sizes
212 #ifdef CONFIG_MEMORY_HOTPLUG
213 /* see spanned/present_pages for more description */
214 seqlock_t span_seqlock;
216 struct free_area free_area[MAX_ORDER];
221 /* Fields commonly accessed by the page reclaim scanner */
223 struct list_head active_list;
224 struct list_head inactive_list;
225 unsigned long nr_scan_active;
226 unsigned long nr_scan_inactive;
227 unsigned long pages_scanned; /* since last reclaim */
228 int all_unreclaimable; /* All pages pinned */
230 /* A count of how many reclaimers are scanning this zone */
231 atomic_t reclaim_in_progress;
233 /* Zone statistics */
234 atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
237 * prev_priority holds the scanning priority for this zone. It is
238 * defined as the scanning priority at which we achieved our reclaim
239 * target at the previous try_to_free_pages() or balance_pgdat()
242 * We use prev_priority as a measure of how much stress page reclaim is
243 * under - it drives the swappiness decision: whether to unmap mapped
246 * Access to both this field is quite racy even on uniprocessor. But
247 * it is expected to average out OK.
253 /* Rarely used or read-mostly fields */
256 * wait_table -- the array holding the hash table
257 * wait_table_hash_nr_entries -- the size of the hash table array
258 * wait_table_bits -- wait_table_size == (1 << wait_table_bits)
260 * The purpose of all these is to keep track of the people
261 * waiting for a page to become available and make them
262 * runnable again when possible. The trouble is that this
263 * consumes a lot of space, especially when so few things
264 * wait on pages at a given time. So instead of using
265 * per-page waitqueues, we use a waitqueue hash table.
267 * The bucket discipline is to sleep on the same queue when
268 * colliding and wake all in that wait queue when removing.
269 * When something wakes, it must check to be sure its page is
270 * truly available, a la thundering herd. The cost of a
271 * collision is great, but given the expected load of the
272 * table, they should be so rare as to be outweighed by the
273 * benefits from the saved space.
275 * __wait_on_page_locked() and unlock_page() in mm/filemap.c, are the
276 * primary users of these fields, and in mm/page_alloc.c
277 * free_area_init_core() performs the initialization of them.
279 wait_queue_head_t * wait_table;
280 unsigned long wait_table_hash_nr_entries;
281 unsigned long wait_table_bits;
284 * Discontig memory support fields.
286 struct pglist_data *zone_pgdat;
287 /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
288 unsigned long zone_start_pfn;
291 * zone_start_pfn, spanned_pages and present_pages are all
292 * protected by span_seqlock. It is a seqlock because it has
293 * to be read outside of zone->lock, and it is done in the main
294 * allocator path. But, it is written quite infrequently.
296 * The lock is declared along with zone->lock because it is
297 * frequently read in proximity to zone->lock. It's good to
298 * give them a chance of being in the same cacheline.
300 unsigned long spanned_pages; /* total size, including holes */
301 unsigned long present_pages; /* amount of memory (excluding holes) */
304 * rarely used fields:
307 } ____cacheline_internodealigned_in_smp;
310 * The "priority" of VM scanning is how much of the queues we will scan in one
311 * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
312 * queues ("queue_length >> 12") during an aging round.
314 #define DEF_PRIORITY 12
316 /* Maximum number of zones on a zonelist */
317 #define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
321 * We cache key information from each zonelist for smaller cache
322 * footprint when scanning for free pages in get_page_from_freelist().
324 * 1) The BITMAP fullzones tracks which zones in a zonelist have come
325 * up short of free memory since the last time (last_fullzone_zap)
326 * we zero'd fullzones.
327 * 2) The array z_to_n[] maps each zone in the zonelist to its node
328 * id, so that we can efficiently evaluate whether that node is
329 * set in the current tasks mems_allowed.
331 * Both fullzones and z_to_n[] are one-to-one with the zonelist,
332 * indexed by a zones offset in the zonelist zones[] array.
334 * The get_page_from_freelist() routine does two scans. During the
335 * first scan, we skip zones whose corresponding bit in 'fullzones'
336 * is set or whose corresponding node in current->mems_allowed (which
337 * comes from cpusets) is not set. During the second scan, we bypass
338 * this zonelist_cache, to ensure we look methodically at each zone.
340 * Once per second, we zero out (zap) fullzones, forcing us to
341 * reconsider nodes that might have regained more free memory.
342 * The field last_full_zap is the time we last zapped fullzones.
344 * This mechanism reduces the amount of time we waste repeatedly
345 * reexaming zones for free memory when they just came up low on
346 * memory momentarilly ago.
348 * The zonelist_cache struct members logically belong in struct
349 * zonelist. However, the mempolicy zonelists constructed for
350 * MPOL_BIND are intentionally variable length (and usually much
351 * shorter). A general purpose mechanism for handling structs with
352 * multiple variable length members is more mechanism than we want
353 * here. We resort to some special case hackery instead.
355 * The MPOL_BIND zonelists don't need this zonelist_cache (in good
356 * part because they are shorter), so we put the fixed length stuff
357 * at the front of the zonelist struct, ending in a variable length
358 * zones[], as is needed by MPOL_BIND.
360 * Then we put the optional zonelist cache on the end of the zonelist
361 * struct. This optional stuff is found by a 'zlcache_ptr' pointer in
362 * the fixed length portion at the front of the struct. This pointer
363 * both enables us to find the zonelist cache, and in the case of
364 * MPOL_BIND zonelists, (which will just set the zlcache_ptr to NULL)
365 * to know that the zonelist cache is not there.
367 * The end result is that struct zonelists come in two flavors:
368 * 1) The full, fixed length version, shown below, and
369 * 2) The custom zonelists for MPOL_BIND.
370 * The custom MPOL_BIND zonelists have a NULL zlcache_ptr and no zlcache.
372 * Even though there may be multiple CPU cores on a node modifying
373 * fullzones or last_full_zap in the same zonelist_cache at the same
374 * time, we don't lock it. This is just hint data - if it is wrong now
375 * and then, the allocator will still function, perhaps a bit slower.
379 struct zonelist_cache {
380 unsigned short z_to_n[MAX_ZONES_PER_ZONELIST]; /* zone->nid */
381 DECLARE_BITMAP(fullzones, MAX_ZONES_PER_ZONELIST); /* zone full? */
382 unsigned long last_full_zap; /* when last zap'd (jiffies) */
385 struct zonelist_cache;
389 * One allocation request operates on a zonelist. A zonelist
390 * is a list of zones, the first one is the 'goal' of the
391 * allocation, the other zones are fallback zones, in decreasing
394 * If zlcache_ptr is not NULL, then it is just the address of zlcache,
395 * as explained above. If zlcache_ptr is NULL, there is no zlcache.
399 struct zonelist_cache *zlcache_ptr; // NULL or &zlcache
400 struct zone *zones[MAX_ZONES_PER_ZONELIST + 1]; // NULL delimited
402 struct zonelist_cache zlcache; // optional ...
406 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
407 struct node_active_region {
408 unsigned long start_pfn;
409 unsigned long end_pfn;
412 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
414 #ifndef CONFIG_DISCONTIGMEM
415 /* The array of struct pages - for discontigmem use pgdat->lmem_map */
416 extern struct page *mem_map;
420 * The pg_data_t structure is used in machines with CONFIG_DISCONTIGMEM
421 * (mostly NUMA machines?) to denote a higher-level memory zone than the
424 * On NUMA machines, each NUMA node would have a pg_data_t to describe
425 * it's memory layout.
427 * Memory statistics and page replacement data structures are maintained on a
431 typedef struct pglist_data {
432 struct zone node_zones[MAX_NR_ZONES];
433 struct zonelist node_zonelists[MAX_NR_ZONES];
435 #ifdef CONFIG_FLAT_NODE_MEM_MAP
436 struct page *node_mem_map;
438 struct bootmem_data *bdata;
439 #ifdef CONFIG_MEMORY_HOTPLUG
441 * Must be held any time you expect node_start_pfn, node_present_pages
442 * or node_spanned_pages stay constant. Holding this will also
443 * guarantee that any pfn_valid() stays that way.
445 * Nests above zone->lock and zone->size_seqlock.
447 spinlock_t node_size_lock;
449 unsigned long node_start_pfn;
450 unsigned long node_present_pages; /* total number of physical pages */
451 unsigned long node_spanned_pages; /* total size of physical page
452 range, including holes */
454 wait_queue_head_t kswapd_wait;
455 struct task_struct *kswapd;
456 int kswapd_max_order;
459 #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
460 #define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)
461 #ifdef CONFIG_FLAT_NODE_MEM_MAP
462 #define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr))
464 #define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr))
466 #define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr))
468 #include <linux/memory_hotplug.h>
470 void get_zone_counts(unsigned long *active, unsigned long *inactive,
471 unsigned long *free);
472 void build_all_zonelists(void);
473 void wakeup_kswapd(struct zone *zone, int order);
474 int zone_watermark_ok(struct zone *z, int order, unsigned long mark,
475 int classzone_idx, int alloc_flags);
476 enum memmap_context {
480 extern int init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,
482 enum memmap_context context);
484 #ifdef CONFIG_HAVE_MEMORY_PRESENT
485 void memory_present(int nid, unsigned long start, unsigned long end);
487 static inline void memory_present(int nid, unsigned long start, unsigned long end) {}
490 #ifdef CONFIG_NEED_NODE_MEMMAP_SIZE
491 unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
495 * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
497 #define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
499 static inline int populated_zone(struct zone *zone)
501 return (!!zone->present_pages);
504 extern int movable_zone;
506 static inline int zone_movable_is_highmem(void)
508 #if defined(CONFIG_HIGHMEM) && defined(CONFIG_ARCH_POPULATES_NODE_MAP)
509 return movable_zone == ZONE_HIGHMEM;
515 static inline int is_highmem_idx(enum zone_type idx)
517 #ifdef CONFIG_HIGHMEM
518 return (idx == ZONE_HIGHMEM ||
519 (idx == ZONE_MOVABLE && zone_movable_is_highmem()));
525 static inline int is_normal_idx(enum zone_type idx)
527 return (idx == ZONE_NORMAL);
531 * is_highmem - helper function to quickly check if a struct zone is a
532 * highmem zone or not. This is an attempt to keep references
533 * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
534 * @zone - pointer to struct zone variable
536 static inline int is_highmem(struct zone *zone)
538 #ifdef CONFIG_HIGHMEM
539 int zone_idx = zone - zone->zone_pgdat->node_zones;
540 return zone_idx == ZONE_HIGHMEM ||
541 (zone_idx == ZONE_MOVABLE && zone_movable_is_highmem());
547 static inline int is_normal(struct zone *zone)
549 return zone == zone->zone_pgdat->node_zones + ZONE_NORMAL;
552 static inline int is_dma32(struct zone *zone)
554 #ifdef CONFIG_ZONE_DMA32
555 return zone == zone->zone_pgdat->node_zones + ZONE_DMA32;
561 static inline int is_dma(struct zone *zone)
563 #ifdef CONFIG_ZONE_DMA
564 return zone == zone->zone_pgdat->node_zones + ZONE_DMA;
570 /* These two functions are used to setup the per zone pages min values */
573 int min_free_kbytes_sysctl_handler(struct ctl_table *, int, struct file *,
574 void __user *, size_t *, loff_t *);
575 extern int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1];
576 int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *, int, struct file *,
577 void __user *, size_t *, loff_t *);
578 int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *, int, struct file *,
579 void __user *, size_t *, loff_t *);
580 int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *, int,
581 struct file *, void __user *, size_t *, loff_t *);
582 int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *, int,
583 struct file *, void __user *, size_t *, loff_t *);
585 extern int numa_zonelist_order_handler(struct ctl_table *, int,
586 struct file *, void __user *, size_t *, loff_t *);
587 extern char numa_zonelist_order[];
588 #define NUMA_ZONELIST_ORDER_LEN 16 /* string buffer size */
590 #include <linux/topology.h>
591 /* Returns the number of the current Node. */
593 #define numa_node_id() (cpu_to_node(raw_smp_processor_id()))
596 #ifndef CONFIG_NEED_MULTIPLE_NODES
598 extern struct pglist_data contig_page_data;
599 #define NODE_DATA(nid) (&contig_page_data)
600 #define NODE_MEM_MAP(nid) mem_map
601 #define MAX_NODES_SHIFT 1
603 #else /* CONFIG_NEED_MULTIPLE_NODES */
605 #include <asm/mmzone.h>
607 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
609 extern struct pglist_data *first_online_pgdat(void);
610 extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat);
611 extern struct zone *next_zone(struct zone *zone);
614 * for_each_pgdat - helper macro to iterate over all nodes
615 * @pgdat - pointer to a pg_data_t variable
617 #define for_each_online_pgdat(pgdat) \
618 for (pgdat = first_online_pgdat(); \
620 pgdat = next_online_pgdat(pgdat))
622 * for_each_zone - helper macro to iterate over all memory zones
623 * @zone - pointer to struct zone variable
625 * The user only needs to declare the zone variable, for_each_zone
628 #define for_each_zone(zone) \
629 for (zone = (first_online_pgdat())->node_zones; \
631 zone = next_zone(zone))
633 #ifdef CONFIG_SPARSEMEM
634 #include <asm/sparsemem.h>
637 #if BITS_PER_LONG == 32
639 * with 32 bit page->flags field, we reserve 9 bits for node/zone info.
640 * there are 4 zones (3 bits) and this leaves 9-3=6 bits for nodes.
642 #define FLAGS_RESERVED 9
644 #elif BITS_PER_LONG == 64
646 * with 64 bit flags field, there's plenty of room.
648 #define FLAGS_RESERVED 32
652 #error BITS_PER_LONG not defined
656 #if !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) && \
657 !defined(CONFIG_ARCH_POPULATES_NODE_MAP)
658 #define early_pfn_to_nid(nid) (0UL)
661 #ifdef CONFIG_FLATMEM
662 #define pfn_to_nid(pfn) (0)
665 #define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
666 #define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
668 #ifdef CONFIG_SPARSEMEM
671 * SECTION_SHIFT #bits space required to store a section #
673 * PA_SECTION_SHIFT physical address to/from section number
674 * PFN_SECTION_SHIFT pfn to/from section number
676 #define SECTIONS_SHIFT (MAX_PHYSMEM_BITS - SECTION_SIZE_BITS)
678 #define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
679 #define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)
681 #define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
683 #define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)
684 #define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))
686 #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
687 #error Allocator MAX_ORDER exceeds SECTION_SIZE
693 * This is, logically, a pointer to an array of struct
694 * pages. However, it is stored with some other magic.
695 * (see sparse.c::sparse_init_one_section())
697 * Additionally during early boot we encode node id of
698 * the location of the section here to guide allocation.
699 * (see sparse.c::memory_present())
701 * Making it a UL at least makes someone do a cast
702 * before using it wrong.
704 unsigned long section_mem_map;
707 #ifdef CONFIG_SPARSEMEM_EXTREME
708 #define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))
710 #define SECTIONS_PER_ROOT 1
713 #define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
714 #define NR_SECTION_ROOTS (NR_MEM_SECTIONS / SECTIONS_PER_ROOT)
715 #define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)
717 #ifdef CONFIG_SPARSEMEM_EXTREME
718 extern struct mem_section *mem_section[NR_SECTION_ROOTS];
720 extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
723 static inline struct mem_section *__nr_to_section(unsigned long nr)
725 if (!mem_section[SECTION_NR_TO_ROOT(nr)])
727 return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK];
729 extern int __section_nr(struct mem_section* ms);
732 * We use the lower bits of the mem_map pointer to store
733 * a little bit of information. There should be at least
734 * 3 bits here due to 32-bit alignment.
736 #define SECTION_MARKED_PRESENT (1UL<<0)
737 #define SECTION_HAS_MEM_MAP (1UL<<1)
738 #define SECTION_MAP_LAST_BIT (1UL<<2)
739 #define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1))
740 #define SECTION_NID_SHIFT 2
742 static inline struct page *__section_mem_map_addr(struct mem_section *section)
744 unsigned long map = section->section_mem_map;
745 map &= SECTION_MAP_MASK;
746 return (struct page *)map;
749 static inline int valid_section(struct mem_section *section)
751 return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));
754 static inline int section_has_mem_map(struct mem_section *section)
756 return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));
759 static inline int valid_section_nr(unsigned long nr)
761 return valid_section(__nr_to_section(nr));
764 static inline struct mem_section *__pfn_to_section(unsigned long pfn)
766 return __nr_to_section(pfn_to_section_nr(pfn));
769 static inline int pfn_valid(unsigned long pfn)
771 if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
773 return valid_section(__nr_to_section(pfn_to_section_nr(pfn)));
777 * These are _only_ used during initialisation, therefore they
778 * can use __initdata ... They could have names to indicate
782 #define pfn_to_nid(pfn) \
784 unsigned long __pfn_to_nid_pfn = (pfn); \
785 page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \
788 #define pfn_to_nid(pfn) (0)
791 #define early_pfn_valid(pfn) pfn_valid(pfn)
792 void sparse_init(void);
794 #define sparse_init() do {} while (0)
795 #define sparse_index_init(_sec, _nid) do {} while (0)
796 #endif /* CONFIG_SPARSEMEM */
798 #ifdef CONFIG_NODES_SPAN_OTHER_NODES
799 #define early_pfn_in_nid(pfn, nid) (early_pfn_to_nid(pfn) == (nid))
801 #define early_pfn_in_nid(pfn, nid) (1)
804 #ifndef early_pfn_valid
805 #define early_pfn_valid(pfn) (1)
808 void memory_present(int nid, unsigned long start, unsigned long end);
809 unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
812 * If it is possible to have holes within a MAX_ORDER_NR_PAGES, then we
813 * need to check pfn validility within that MAX_ORDER_NR_PAGES block.
814 * pfn_valid_within() should be used in this case; we optimise this away
815 * when we have no holes within a MAX_ORDER_NR_PAGES block.
817 #ifdef CONFIG_HOLES_IN_ZONE
818 #define pfn_valid_within(pfn) pfn_valid(pfn)
820 #define pfn_valid_within(pfn) (1)
823 #endif /* !__ASSEMBLY__ */
824 #endif /* __KERNEL__ */
825 #endif /* _LINUX_MMZONE_H */