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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _LINUX_MMZONE_H
2#define _LINUX_MMZONE_H
3
Linus Torvalds1da177e2005-04-16 15:20:36 -07004#ifndef __ASSEMBLY__
Christoph Lameter97965472008-04-28 02:12:54 -07005#ifndef __GENERATING_BOUNDS_H
Linus Torvalds1da177e2005-04-16 15:20:36 -07006
Linus Torvalds1da177e2005-04-16 15:20:36 -07007#include <linux/spinlock.h>
8#include <linux/list.h>
9#include <linux/wait.h>
David Rientjese815af92007-10-16 23:25:54 -070010#include <linux/bitops.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <linux/cache.h>
12#include <linux/threads.h>
13#include <linux/numa.h>
14#include <linux/init.h>
Dave Hansenbdc8cb92005-10-29 18:16:53 -070015#include <linux/seqlock.h>
KAMEZAWA Hiroyuki8357f862006-03-27 01:15:57 -080016#include <linux/nodemask.h>
Mel Gorman835c1342007-10-16 01:25:47 -070017#include <linux/pageblock-flags.h>
Sam Ravnborg01fc0ac2009-04-19 21:57:19 +020018#include <generated/bounds.h>
Arun Sharma600634972011-07-26 16:09:06 -070019#include <linux/atomic.h>
Ralf Baechle93ff66b2006-06-04 02:51:29 -070020#include <asm/page.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021
22/* Free memory management - zoned buddy allocator. */
23#ifndef CONFIG_FORCE_MAX_ZONEORDER
24#define MAX_ORDER 11
25#else
26#define MAX_ORDER CONFIG_FORCE_MAX_ZONEORDER
27#endif
Bob Piccoe984bb42006-05-20 15:00:31 -070028#define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1))
Linus Torvalds1da177e2005-04-16 15:20:36 -070029
Andy Whitcroft5ad333e2007-07-17 04:03:16 -070030/*
31 * PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed
32 * costly to service. That is between allocation orders which should
Wang YanQing35fca532012-04-15 20:42:28 +080033 * coalesce naturally under reasonable reclaim pressure and those which
Andy Whitcroft5ad333e2007-07-17 04:03:16 -070034 * will not.
35 */
36#define PAGE_ALLOC_COSTLY_ORDER 3
37
Michal Nazarewicz47118af2011-12-29 13:09:50 +010038enum {
39 MIGRATE_UNMOVABLE,
40 MIGRATE_RECLAIMABLE,
41 MIGRATE_MOVABLE,
42 MIGRATE_PCPTYPES, /* the number of types on the pcp lists */
43 MIGRATE_RESERVE = MIGRATE_PCPTYPES,
44#ifdef CONFIG_CMA
45 /*
46 * MIGRATE_CMA migration type is designed to mimic the way
47 * ZONE_MOVABLE works. Only movable pages can be allocated
48 * from MIGRATE_CMA pageblocks and page allocator never
49 * implicitly change migration type of MIGRATE_CMA pageblock.
50 *
51 * The way to use it is to change migratetype of a range of
52 * pageblocks to MIGRATE_CMA which can be done by
53 * __free_pageblock_cma() function. What is important though
54 * is that a range of pageblocks must be aligned to
55 * MAX_ORDER_NR_PAGES should biggest page be bigger then
56 * a single pageblock.
57 */
58 MIGRATE_CMA,
59#endif
60 MIGRATE_ISOLATE, /* can't allocate from here */
61 MIGRATE_TYPES
62};
63
64#ifdef CONFIG_CMA
65# define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA)
66#else
67# define is_migrate_cma(migratetype) false
68#endif
Mel Gormanb2a0ac82007-10-16 01:25:48 -070069
70#define for_each_migratetype_order(order, type) \
71 for (order = 0; order < MAX_ORDER; order++) \
72 for (type = 0; type < MIGRATE_TYPES; type++)
73
Mel Gorman467c9962007-10-16 01:26:02 -070074extern int page_group_by_mobility_disabled;
75
76static inline int get_pageblock_migratetype(struct page *page)
77{
Mel Gorman467c9962007-10-16 01:26:02 -070078 return get_pageblock_flags_group(page, PB_migrate, PB_migrate_end);
79}
80
Linus Torvalds1da177e2005-04-16 15:20:36 -070081struct free_area {
Mel Gormanb2a0ac82007-10-16 01:25:48 -070082 struct list_head free_list[MIGRATE_TYPES];
Linus Torvalds1da177e2005-04-16 15:20:36 -070083 unsigned long nr_free;
84};
85
86struct pglist_data;
87
88/*
89 * zone->lock and zone->lru_lock are two of the hottest locks in the kernel.
90 * So add a wild amount of padding here to ensure that they fall into separate
91 * cachelines. There are very few zone structures in the machine, so space
92 * consumption is not a concern here.
93 */
94#if defined(CONFIG_SMP)
95struct zone_padding {
96 char x[0];
Ravikiran G Thirumalai22fc6ec2006-01-08 01:01:27 -080097} ____cacheline_internodealigned_in_smp;
Linus Torvalds1da177e2005-04-16 15:20:36 -070098#define ZONE_PADDING(name) struct zone_padding name;
99#else
100#define ZONE_PADDING(name)
101#endif
102
Christoph Lameter2244b952006-06-30 01:55:33 -0700103enum zone_stat_item {
Christoph Lameter51ed4492007-02-10 01:43:02 -0800104 /* First 128 byte cacheline (assuming 64 bit words) */
Christoph Lameterd23ad422007-02-10 01:43:02 -0800105 NR_FREE_PAGES,
Christoph Lameterb69408e2008-10-18 20:26:14 -0700106 NR_LRU_BASE,
Rik van Riel4f98a2f2008-10-18 20:26:32 -0700107 NR_INACTIVE_ANON = NR_LRU_BASE, /* must match order of LRU_[IN]ACTIVE */
108 NR_ACTIVE_ANON, /* " " " " " */
109 NR_INACTIVE_FILE, /* " " " " " */
110 NR_ACTIVE_FILE, /* " " " " " */
Lee Schermerhorn894bc312008-10-18 20:26:39 -0700111 NR_UNEVICTABLE, /* " " " " " */
Nick Piggin5344b7e2008-10-18 20:26:51 -0700112 NR_MLOCK, /* mlock()ed pages found and moved off LRU */
Christoph Lameterf3dbd342006-06-30 01:55:36 -0700113 NR_ANON_PAGES, /* Mapped anonymous pages */
114 NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
Christoph Lameter65ba55f2006-06-30 01:55:34 -0700115 only modified from process context */
Christoph Lameter347ce432006-06-30 01:55:35 -0700116 NR_FILE_PAGES,
Christoph Lameterb1e7a8f2006-06-30 01:55:39 -0700117 NR_FILE_DIRTY,
Christoph Lameterce866b32006-06-30 01:55:40 -0700118 NR_WRITEBACK,
Christoph Lameter51ed4492007-02-10 01:43:02 -0800119 NR_SLAB_RECLAIMABLE,
120 NR_SLAB_UNRECLAIMABLE,
121 NR_PAGETABLE, /* used for pagetables */
KOSAKI Motohiroc6a7f572009-09-21 17:01:32 -0700122 NR_KERNEL_STACK,
123 /* Second 128 byte cacheline */
Christoph Lameterfd39fc82006-06-30 01:55:40 -0700124 NR_UNSTABLE_NFS, /* NFS unstable pages */
Christoph Lameterd2c5e302006-06-30 01:55:41 -0700125 NR_BOUNCE,
Andrew Mortone129b5c2006-09-27 01:50:00 -0700126 NR_VMSCAN_WRITE,
Mel Gorman49ea7eb2011-10-31 17:07:59 -0700127 NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */
Miklos Szeredifc3ba692008-04-30 00:54:38 -0700128 NR_WRITEBACK_TEMP, /* Writeback using temporary buffers */
KOSAKI Motohiroa7312862009-09-21 17:01:37 -0700129 NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */
130 NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */
KOSAKI Motohiro4b021082009-09-21 17:01:33 -0700131 NR_SHMEM, /* shmem pages (included tmpfs/GEM pages) */
Michael Rubinea941f02010-10-26 14:21:35 -0700132 NR_DIRTIED, /* page dirtyings since bootup */
133 NR_WRITTEN, /* page writings since bootup */
Christoph Lameterca889e62006-06-30 01:55:44 -0700134#ifdef CONFIG_NUMA
135 NUMA_HIT, /* allocated in intended node */
136 NUMA_MISS, /* allocated in non intended node */
137 NUMA_FOREIGN, /* was intended here, hit elsewhere */
138 NUMA_INTERLEAVE_HIT, /* interleaver preferred this zone */
139 NUMA_LOCAL, /* allocation from local node */
140 NUMA_OTHER, /* allocation from other node */
141#endif
Andrea Arcangeli79134172011-01-13 15:46:58 -0800142 NR_ANON_TRANSPARENT_HUGEPAGES,
Bartlomiej Zolnierkiewiczd1ce7492012-10-08 16:32:02 -0700143 NR_FREE_CMA_PAGES,
Christoph Lameter2244b952006-06-30 01:55:33 -0700144 NR_VM_ZONE_STAT_ITEMS };
145
Rik van Riel4f98a2f2008-10-18 20:26:32 -0700146/*
147 * We do arithmetic on the LRU lists in various places in the code,
148 * so it is important to keep the active lists LRU_ACTIVE higher in
149 * the array than the corresponding inactive lists, and to keep
150 * the *_FILE lists LRU_FILE higher than the corresponding _ANON lists.
151 *
152 * This has to be kept in sync with the statistics in zone_stat_item
153 * above and the descriptions in vmstat_text in mm/vmstat.c
154 */
155#define LRU_BASE 0
156#define LRU_ACTIVE 1
157#define LRU_FILE 2
158
Christoph Lameterb69408e2008-10-18 20:26:14 -0700159enum lru_list {
Rik van Riel4f98a2f2008-10-18 20:26:32 -0700160 LRU_INACTIVE_ANON = LRU_BASE,
161 LRU_ACTIVE_ANON = LRU_BASE + LRU_ACTIVE,
162 LRU_INACTIVE_FILE = LRU_BASE + LRU_FILE,
163 LRU_ACTIVE_FILE = LRU_BASE + LRU_FILE + LRU_ACTIVE,
Lee Schermerhorn894bc312008-10-18 20:26:39 -0700164 LRU_UNEVICTABLE,
Lee Schermerhorn894bc312008-10-18 20:26:39 -0700165 NR_LRU_LISTS
166};
Christoph Lameterb69408e2008-10-18 20:26:14 -0700167
Hugh Dickins41113042012-01-12 17:20:01 -0800168#define for_each_lru(lru) for (lru = 0; lru < NR_LRU_LISTS; lru++)
Christoph Lameterb69408e2008-10-18 20:26:14 -0700169
Hugh Dickins41113042012-01-12 17:20:01 -0800170#define for_each_evictable_lru(lru) for (lru = 0; lru <= LRU_ACTIVE_FILE; lru++)
Lee Schermerhorn894bc312008-10-18 20:26:39 -0700171
Hugh Dickins41113042012-01-12 17:20:01 -0800172static inline int is_file_lru(enum lru_list lru)
Rik van Riel4f98a2f2008-10-18 20:26:32 -0700173{
Hugh Dickins41113042012-01-12 17:20:01 -0800174 return (lru == LRU_INACTIVE_FILE || lru == LRU_ACTIVE_FILE);
Rik van Riel4f98a2f2008-10-18 20:26:32 -0700175}
176
Hugh Dickins41113042012-01-12 17:20:01 -0800177static inline int is_active_lru(enum lru_list lru)
Christoph Lameterb69408e2008-10-18 20:26:14 -0700178{
Hugh Dickins41113042012-01-12 17:20:01 -0800179 return (lru == LRU_ACTIVE_ANON || lru == LRU_ACTIVE_FILE);
Christoph Lameterb69408e2008-10-18 20:26:14 -0700180}
181
Hugh Dickins41113042012-01-12 17:20:01 -0800182static inline int is_unevictable_lru(enum lru_list lru)
Lee Schermerhorn894bc312008-10-18 20:26:39 -0700183{
Hugh Dickins41113042012-01-12 17:20:01 -0800184 return (lru == LRU_UNEVICTABLE);
Lee Schermerhorn894bc312008-10-18 20:26:39 -0700185}
186
Hugh Dickins89abfab2012-05-29 15:06:53 -0700187struct zone_reclaim_stat {
188 /*
189 * The pageout code in vmscan.c keeps track of how many of the
Jiri Kosina59f91e52012-06-29 14:45:58 +0200190 * mem/swap backed and file backed pages are referenced.
Hugh Dickins89abfab2012-05-29 15:06:53 -0700191 * The higher the rotated/scanned ratio, the more valuable
192 * that cache is.
193 *
194 * The anon LRU stats live in [0], file LRU stats in [1]
195 */
196 unsigned long recent_rotated[2];
197 unsigned long recent_scanned[2];
198};
199
Johannes Weiner6290df52012-01-12 17:18:10 -0800200struct lruvec {
201 struct list_head lists[NR_LRU_LISTS];
Hugh Dickins89abfab2012-05-29 15:06:53 -0700202 struct zone_reclaim_stat reclaim_stat;
Andrew Mortonc255a452012-07-31 16:43:02 -0700203#ifdef CONFIG_MEMCG
Konstantin Khlebnikov7f5e86c2012-05-29 15:06:58 -0700204 struct zone *zone;
205#endif
Johannes Weiner6290df52012-01-12 17:18:10 -0800206};
207
KAMEZAWA Hiroyukibb2a0de2011-07-26 16:08:22 -0700208/* Mask used at gathering information at once (see memcontrol.c) */
209#define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE))
210#define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON))
KAMEZAWA Hiroyukibb2a0de2011-07-26 16:08:22 -0700211#define LRU_ALL ((1 << NR_LRU_LISTS) - 1)
212
Minchan Kim39deaf82011-10-31 17:06:51 -0700213/* Isolate clean file */
Konstantin Khlebnikovf3fd4a62012-05-29 15:06:54 -0700214#define ISOLATE_CLEAN ((__force isolate_mode_t)0x1)
Minchan Kimf80c0672011-10-31 17:06:55 -0700215/* Isolate unmapped file */
Konstantin Khlebnikovf3fd4a62012-05-29 15:06:54 -0700216#define ISOLATE_UNMAPPED ((__force isolate_mode_t)0x2)
Mel Gormanc8244932012-01-12 17:19:38 -0800217/* Isolate for asynchronous migration */
Konstantin Khlebnikovf3fd4a62012-05-29 15:06:54 -0700218#define ISOLATE_ASYNC_MIGRATE ((__force isolate_mode_t)0x4)
Minchan Kime46a2872012-10-08 16:33:48 -0700219/* Isolate unevictable pages */
220#define ISOLATE_UNEVICTABLE ((__force isolate_mode_t)0x8)
Minchan Kim4356f212011-10-31 17:06:47 -0700221
222/* LRU Isolation modes. */
223typedef unsigned __bitwise__ isolate_mode_t;
224
Mel Gorman41858962009-06-16 15:32:12 -0700225enum zone_watermarks {
226 WMARK_MIN,
227 WMARK_LOW,
228 WMARK_HIGH,
229 NR_WMARK
230};
231
232#define min_wmark_pages(z) (z->watermark[WMARK_MIN])
233#define low_wmark_pages(z) (z->watermark[WMARK_LOW])
234#define high_wmark_pages(z) (z->watermark[WMARK_HIGH])
235
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236struct per_cpu_pages {
237 int count; /* number of pages in the list */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238 int high; /* high watermark, emptying needed */
239 int batch; /* chunk size for buddy add/remove */
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700240
241 /* Lists of pages, one per migrate type stored on the pcp-lists */
242 struct list_head lists[MIGRATE_PCPTYPES];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243};
244
245struct per_cpu_pageset {
Christoph Lameter3dfa5722008-02-04 22:29:19 -0800246 struct per_cpu_pages pcp;
Christoph Lameter4037d452007-05-09 02:35:14 -0700247#ifdef CONFIG_NUMA
248 s8 expire;
249#endif
Christoph Lameter2244b952006-06-30 01:55:33 -0700250#ifdef CONFIG_SMP
Christoph Lameterdf9ecab2006-08-31 21:27:35 -0700251 s8 stat_threshold;
Christoph Lameter2244b952006-06-30 01:55:33 -0700252 s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS];
253#endif
Christoph Lameter99dcc3e2010-01-05 15:34:51 +0900254};
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700255
Christoph Lameter97965472008-04-28 02:12:54 -0700256#endif /* !__GENERATING_BOUNDS.H */
257
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700258enum zone_type {
Christoph Lameter4b51d662007-02-10 01:43:10 -0800259#ifdef CONFIG_ZONE_DMA
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700260 /*
261 * ZONE_DMA is used when there are devices that are not able
262 * to do DMA to all of addressable memory (ZONE_NORMAL). Then we
263 * carve out the portion of memory that is needed for these devices.
264 * The range is arch specific.
265 *
266 * Some examples
267 *
268 * Architecture Limit
269 * ---------------------------
270 * parisc, ia64, sparc <4G
271 * s390 <2G
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700272 * arm Various
273 * alpha Unlimited or 0-16MB.
274 *
275 * i386, x86_64 and multiple other arches
276 * <16M.
277 */
278 ZONE_DMA,
Christoph Lameter4b51d662007-02-10 01:43:10 -0800279#endif
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700280#ifdef CONFIG_ZONE_DMA32
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700281 /*
282 * x86_64 needs two ZONE_DMAs because it supports devices that are
283 * only able to do DMA to the lower 16M but also 32 bit devices that
284 * can only do DMA areas below 4G.
285 */
286 ZONE_DMA32,
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700287#endif
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700288 /*
289 * Normal addressable memory is in ZONE_NORMAL. DMA operations can be
290 * performed on pages in ZONE_NORMAL if the DMA devices support
291 * transfers to all addressable memory.
292 */
293 ZONE_NORMAL,
Christoph Lametere53ef382006-09-25 23:31:14 -0700294#ifdef CONFIG_HIGHMEM
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700295 /*
296 * A memory area that is only addressable by the kernel through
297 * mapping portions into its own address space. This is for example
298 * used by i386 to allow the kernel to address the memory beyond
299 * 900MB. The kernel will set up special mappings (page
300 * table entries on i386) for each page that the kernel needs to
301 * access.
302 */
303 ZONE_HIGHMEM,
Christoph Lametere53ef382006-09-25 23:31:14 -0700304#endif
Mel Gorman2a1e2742007-07-17 04:03:12 -0700305 ZONE_MOVABLE,
Christoph Lameter97965472008-04-28 02:12:54 -0700306 __MAX_NR_ZONES
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700307};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308
Christoph Lameter97965472008-04-28 02:12:54 -0700309#ifndef __GENERATING_BOUNDS_H
310
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311/*
312 * When a memory allocation must conform to specific limitations (such
313 * as being suitable for DMA) the caller will pass in hints to the
314 * allocator in the gfp_mask, in the zone modifier bits. These bits
315 * are used to select a priority ordered list of memory zones which
Christoph Lameter19655d32006-09-25 23:31:19 -0700316 * match the requested limits. See gfp_zone() in include/linux/gfp.h
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 */
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700318
Christoph Lameter97965472008-04-28 02:12:54 -0700319#if MAX_NR_ZONES < 2
Christoph Lameter4b51d662007-02-10 01:43:10 -0800320#define ZONES_SHIFT 0
Christoph Lameter97965472008-04-28 02:12:54 -0700321#elif MAX_NR_ZONES <= 2
Christoph Lameter19655d32006-09-25 23:31:19 -0700322#define ZONES_SHIFT 1
Christoph Lameter97965472008-04-28 02:12:54 -0700323#elif MAX_NR_ZONES <= 4
Christoph Lameter19655d32006-09-25 23:31:19 -0700324#define ZONES_SHIFT 2
Christoph Lameter4b51d662007-02-10 01:43:10 -0800325#else
326#error ZONES_SHIFT -- too many zones configured adjust calculation
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700327#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329struct zone {
330 /* Fields commonly accessed by the page allocator */
Mel Gorman41858962009-06-16 15:32:12 -0700331
332 /* zone watermarks, access with *_wmark_pages(zone) macros */
333 unsigned long watermark[NR_WMARK];
334
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 /*
Christoph Lameteraa454842010-09-09 16:38:17 -0700336 * When free pages are below this point, additional steps are taken
337 * when reading the number of free pages to avoid per-cpu counter
338 * drift allowing watermarks to be breached
339 */
340 unsigned long percpu_drift_mark;
341
342 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 * We don't know if the memory that we're going to allocate will be freeable
344 * or/and it will be released eventually, so to avoid totally wasting several
345 * GB of ram we must reserve some of the lower zone memory (otherwise we risk
346 * to run OOM on the lower zones despite there's tons of freeable ram
347 * on the higher zones). This array is recalculated at runtime if the
348 * sysctl_lowmem_reserve_ratio sysctl changes.
349 */
350 unsigned long lowmem_reserve[MAX_NR_ZONES];
351
Johannes Weinerab8fabd2012-01-10 15:07:42 -0800352 /*
353 * This is a per-zone reserve of pages that should not be
354 * considered dirtyable memory.
355 */
356 unsigned long dirty_balance_reserve;
357
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700358#ifdef CONFIG_NUMA
Christoph Lameterd5f541e2006-09-27 01:50:08 -0700359 int node;
Christoph Lameter96146342006-07-03 00:24:13 -0700360 /*
361 * zone reclaim becomes active if more unmapped pages exist.
362 */
Christoph Lameter8417bba2006-09-25 23:31:51 -0700363 unsigned long min_unmapped_pages;
Christoph Lameter0ff38492006-09-25 23:31:52 -0700364 unsigned long min_slab_pages;
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700365#endif
Tejun Heo43cf38e2010-02-02 14:38:57 +0900366 struct per_cpu_pageset __percpu *pageset;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 /*
368 * free areas of different sizes
369 */
370 spinlock_t lock;
KOSAKI Motohiro93e4a892010-03-05 13:41:55 -0800371 int all_unreclaimable; /* All pages pinned */
Mel Gormanbb13ffe2012-10-08 16:32:41 -0700372#if defined CONFIG_COMPACTION || defined CONFIG_CMA
Mel Gorman62997022012-10-08 16:32:47 -0700373 /* Set to true when the PG_migrate_skip bits should be cleared */
374 bool compact_blockskip_flush;
Mel Gormanc89511a2012-10-08 16:32:45 -0700375
376 /* pfns where compaction scanners should start */
377 unsigned long compact_cached_free_pfn;
378 unsigned long compact_cached_migrate_pfn;
Mel Gormanbb13ffe2012-10-08 16:32:41 -0700379#endif
Dave Hansenbdc8cb92005-10-29 18:16:53 -0700380#ifdef CONFIG_MEMORY_HOTPLUG
381 /* see spanned/present_pages for more description */
382 seqlock_t span_seqlock;
383#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384 struct free_area free_area[MAX_ORDER];
385
Mel Gorman835c1342007-10-16 01:25:47 -0700386#ifndef CONFIG_SPARSEMEM
387 /*
Mel Gormand9c23402007-10-16 01:26:01 -0700388 * Flags for a pageblock_nr_pages block. See pageblock-flags.h.
Mel Gorman835c1342007-10-16 01:25:47 -0700389 * In SPARSEMEM, this map is stored in struct mem_section
390 */
391 unsigned long *pageblock_flags;
392#endif /* CONFIG_SPARSEMEM */
393
Mel Gorman4f92e252010-05-24 14:32:32 -0700394#ifdef CONFIG_COMPACTION
395 /*
396 * On compaction failure, 1<<compact_defer_shift compactions
397 * are skipped before trying again. The number attempted since
398 * last failure is tracked with compact_considered.
399 */
400 unsigned int compact_considered;
401 unsigned int compact_defer_shift;
Rik van Rielaff62242012-03-21 16:33:52 -0700402 int compact_order_failed;
Mel Gorman4f92e252010-05-24 14:32:32 -0700403#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404
405 ZONE_PADDING(_pad1_)
406
407 /* Fields commonly accessed by the page reclaim scanner */
Johannes Weiner6290df52012-01-12 17:18:10 -0800408 spinlock_t lru_lock;
409 struct lruvec lruvec;
Rik van Riel4f98a2f2008-10-18 20:26:32 -0700410
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411 unsigned long pages_scanned; /* since last reclaim */
David Rientjese815af92007-10-16 23:25:54 -0700412 unsigned long flags; /* zone flags, see below */
Martin Hicks753ee722005-06-21 17:14:41 -0700413
Christoph Lameter2244b952006-06-30 01:55:33 -0700414 /* Zone statistics */
415 atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
Christoph Lameter9eeff232006-01-18 17:42:31 -0800416
417 /*
Rik van Riel556adec2008-10-18 20:26:34 -0700418 * The target ratio of ACTIVE_ANON to INACTIVE_ANON pages on
419 * this zone's LRU. Maintained by the pageout code.
420 */
421 unsigned int inactive_ratio;
422
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423
424 ZONE_PADDING(_pad2_)
425 /* Rarely used or read-mostly fields */
426
427 /*
428 * wait_table -- the array holding the hash table
Yasunori Goto02b694d2006-06-23 02:03:08 -0700429 * wait_table_hash_nr_entries -- the size of the hash table array
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430 * wait_table_bits -- wait_table_size == (1 << wait_table_bits)
431 *
432 * The purpose of all these is to keep track of the people
433 * waiting for a page to become available and make them
434 * runnable again when possible. The trouble is that this
435 * consumes a lot of space, especially when so few things
436 * wait on pages at a given time. So instead of using
437 * per-page waitqueues, we use a waitqueue hash table.
438 *
439 * The bucket discipline is to sleep on the same queue when
440 * colliding and wake all in that wait queue when removing.
441 * When something wakes, it must check to be sure its page is
442 * truly available, a la thundering herd. The cost of a
443 * collision is great, but given the expected load of the
444 * table, they should be so rare as to be outweighed by the
445 * benefits from the saved space.
446 *
447 * __wait_on_page_locked() and unlock_page() in mm/filemap.c, are the
448 * primary users of these fields, and in mm/page_alloc.c
449 * free_area_init_core() performs the initialization of them.
450 */
451 wait_queue_head_t * wait_table;
Yasunori Goto02b694d2006-06-23 02:03:08 -0700452 unsigned long wait_table_hash_nr_entries;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453 unsigned long wait_table_bits;
454
455 /*
456 * Discontig memory support fields.
457 */
458 struct pglist_data *zone_pgdat;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459 /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
460 unsigned long zone_start_pfn;
461
Dave Hansenbdc8cb92005-10-29 18:16:53 -0700462 /*
Jiang Liu9feedc92012-12-12 13:52:12 -0800463 * spanned_pages is the total pages spanned by the zone, including
464 * holes, which is calculated as:
465 * spanned_pages = zone_end_pfn - zone_start_pfn;
Dave Hansenbdc8cb92005-10-29 18:16:53 -0700466 *
Jiang Liu9feedc92012-12-12 13:52:12 -0800467 * present_pages is physical pages existing within the zone, which
468 * is calculated as:
469 * present_pages = spanned_pages - absent_pages(pags in holes);
470 *
471 * managed_pages is present pages managed by the buddy system, which
472 * is calculated as (reserved_pages includes pages allocated by the
473 * bootmem allocator):
474 * managed_pages = present_pages - reserved_pages;
475 *
476 * So present_pages may be used by memory hotplug or memory power
477 * management logic to figure out unmanaged pages by checking
478 * (present_pages - managed_pages). And managed_pages should be used
479 * by page allocator and vm scanner to calculate all kinds of watermarks
480 * and thresholds.
481 *
482 * Locking rules:
483 *
484 * zone_start_pfn and spanned_pages are protected by span_seqlock.
485 * It is a seqlock because it has to be read outside of zone->lock,
486 * and it is done in the main allocator path. But, it is written
487 * quite infrequently.
488 *
489 * The span_seq lock is declared along with zone->lock because it is
Dave Hansenbdc8cb92005-10-29 18:16:53 -0700490 * frequently read in proximity to zone->lock. It's good to
491 * give them a chance of being in the same cacheline.
Jiang Liu9feedc92012-12-12 13:52:12 -0800492 *
493 * Write access to present_pages and managed_pages at runtime should
494 * be protected by lock_memory_hotplug()/unlock_memory_hotplug().
495 * Any reader who can't tolerant drift of present_pages and
496 * managed_pages should hold memory hotplug lock to get a stable value.
Dave Hansenbdc8cb92005-10-29 18:16:53 -0700497 */
Jiang Liu9feedc92012-12-12 13:52:12 -0800498 unsigned long spanned_pages;
499 unsigned long present_pages;
500 unsigned long managed_pages;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501
502 /*
503 * rarely used fields:
504 */
Helge Deller15ad7cd2006-12-06 20:40:36 -0800505 const char *name;
Ravikiran G Thirumalai22fc6ec2006-01-08 01:01:27 -0800506} ____cacheline_internodealigned_in_smp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700507
David Rientjese815af92007-10-16 23:25:54 -0700508typedef enum {
David Rientjese815af92007-10-16 23:25:54 -0700509 ZONE_RECLAIM_LOCKED, /* prevents concurrent reclaim */
David Rientjes098d7f12007-10-16 23:25:55 -0700510 ZONE_OOM_LOCKED, /* zone is in OOM killer zonelist */
Mel Gorman0e093d992010-10-26 14:21:45 -0700511 ZONE_CONGESTED, /* zone has many dirty pages backed by
512 * a congested BDI
513 */
David Rientjese815af92007-10-16 23:25:54 -0700514} zone_flags_t;
515
516static inline void zone_set_flag(struct zone *zone, zone_flags_t flag)
517{
518 set_bit(flag, &zone->flags);
519}
David Rientjesd773ed62007-10-16 23:26:01 -0700520
521static inline int zone_test_and_set_flag(struct zone *zone, zone_flags_t flag)
522{
523 return test_and_set_bit(flag, &zone->flags);
524}
525
David Rientjese815af92007-10-16 23:25:54 -0700526static inline void zone_clear_flag(struct zone *zone, zone_flags_t flag)
527{
528 clear_bit(flag, &zone->flags);
529}
530
Mel Gorman0e093d992010-10-26 14:21:45 -0700531static inline int zone_is_reclaim_congested(const struct zone *zone)
532{
533 return test_bit(ZONE_CONGESTED, &zone->flags);
534}
535
David Rientjese815af92007-10-16 23:25:54 -0700536static inline int zone_is_reclaim_locked(const struct zone *zone)
537{
538 return test_bit(ZONE_RECLAIM_LOCKED, &zone->flags);
539}
David Rientjesd773ed62007-10-16 23:26:01 -0700540
David Rientjes098d7f12007-10-16 23:25:55 -0700541static inline int zone_is_oom_locked(const struct zone *zone)
542{
543 return test_bit(ZONE_OOM_LOCKED, &zone->flags);
544}
David Rientjese815af92007-10-16 23:25:54 -0700545
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546/*
547 * The "priority" of VM scanning is how much of the queues we will scan in one
548 * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
549 * queues ("queue_length >> 12") during an aging round.
550 */
551#define DEF_PRIORITY 12
552
Paul Jackson9276b1bc2006-12-06 20:31:48 -0800553/* Maximum number of zones on a zonelist */
554#define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
555
556#ifdef CONFIG_NUMA
Christoph Lameter523b9452007-10-16 01:25:37 -0700557
558/*
Pete Zaitcev25a64ec2011-02-03 22:43:48 -0700559 * The NUMA zonelists are doubled because we need zonelists that restrict the
Christoph Lameter523b9452007-10-16 01:25:37 -0700560 * allocations to a single node for GFP_THISNODE.
561 *
Mel Gorman54a6eb52008-04-28 02:12:16 -0700562 * [0] : Zonelist with fallback
563 * [1] : No fallback (GFP_THISNODE)
Christoph Lameter523b9452007-10-16 01:25:37 -0700564 */
Mel Gorman54a6eb52008-04-28 02:12:16 -0700565#define MAX_ZONELISTS 2
Christoph Lameter523b9452007-10-16 01:25:37 -0700566
567
Paul Jackson9276b1bc2006-12-06 20:31:48 -0800568/*
569 * We cache key information from each zonelist for smaller cache
570 * footprint when scanning for free pages in get_page_from_freelist().
571 *
572 * 1) The BITMAP fullzones tracks which zones in a zonelist have come
573 * up short of free memory since the last time (last_fullzone_zap)
574 * we zero'd fullzones.
575 * 2) The array z_to_n[] maps each zone in the zonelist to its node
576 * id, so that we can efficiently evaluate whether that node is
577 * set in the current tasks mems_allowed.
578 *
579 * Both fullzones and z_to_n[] are one-to-one with the zonelist,
580 * indexed by a zones offset in the zonelist zones[] array.
581 *
582 * The get_page_from_freelist() routine does two scans. During the
583 * first scan, we skip zones whose corresponding bit in 'fullzones'
584 * is set or whose corresponding node in current->mems_allowed (which
585 * comes from cpusets) is not set. During the second scan, we bypass
586 * this zonelist_cache, to ensure we look methodically at each zone.
587 *
588 * Once per second, we zero out (zap) fullzones, forcing us to
589 * reconsider nodes that might have regained more free memory.
590 * The field last_full_zap is the time we last zapped fullzones.
591 *
592 * This mechanism reduces the amount of time we waste repeatedly
593 * reexaming zones for free memory when they just came up low on
594 * memory momentarilly ago.
595 *
596 * The zonelist_cache struct members logically belong in struct
597 * zonelist. However, the mempolicy zonelists constructed for
598 * MPOL_BIND are intentionally variable length (and usually much
599 * shorter). A general purpose mechanism for handling structs with
600 * multiple variable length members is more mechanism than we want
601 * here. We resort to some special case hackery instead.
602 *
603 * The MPOL_BIND zonelists don't need this zonelist_cache (in good
604 * part because they are shorter), so we put the fixed length stuff
605 * at the front of the zonelist struct, ending in a variable length
606 * zones[], as is needed by MPOL_BIND.
607 *
608 * Then we put the optional zonelist cache on the end of the zonelist
609 * struct. This optional stuff is found by a 'zlcache_ptr' pointer in
610 * the fixed length portion at the front of the struct. This pointer
611 * both enables us to find the zonelist cache, and in the case of
612 * MPOL_BIND zonelists, (which will just set the zlcache_ptr to NULL)
613 * to know that the zonelist cache is not there.
614 *
615 * The end result is that struct zonelists come in two flavors:
616 * 1) The full, fixed length version, shown below, and
617 * 2) The custom zonelists for MPOL_BIND.
618 * The custom MPOL_BIND zonelists have a NULL zlcache_ptr and no zlcache.
619 *
620 * Even though there may be multiple CPU cores on a node modifying
621 * fullzones or last_full_zap in the same zonelist_cache at the same
622 * time, we don't lock it. This is just hint data - if it is wrong now
623 * and then, the allocator will still function, perhaps a bit slower.
624 */
625
626
627struct zonelist_cache {
Paul Jackson9276b1bc2006-12-06 20:31:48 -0800628 unsigned short z_to_n[MAX_ZONES_PER_ZONELIST]; /* zone->nid */
Paul Jackson7253f4e2006-12-06 20:31:49 -0800629 DECLARE_BITMAP(fullzones, MAX_ZONES_PER_ZONELIST); /* zone full? */
Paul Jackson9276b1bc2006-12-06 20:31:48 -0800630 unsigned long last_full_zap; /* when last zap'd (jiffies) */
631};
632#else
Mel Gorman54a6eb52008-04-28 02:12:16 -0700633#define MAX_ZONELISTS 1
Paul Jackson9276b1bc2006-12-06 20:31:48 -0800634struct zonelist_cache;
635#endif
636
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637/*
Mel Gormandd1a2392008-04-28 02:12:17 -0700638 * This struct contains information about a zone in a zonelist. It is stored
639 * here to avoid dereferences into large structures and lookups of tables
640 */
641struct zoneref {
642 struct zone *zone; /* Pointer to actual zone */
643 int zone_idx; /* zone_idx(zoneref->zone) */
644};
645
646/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647 * One allocation request operates on a zonelist. A zonelist
648 * is a list of zones, the first one is the 'goal' of the
649 * allocation, the other zones are fallback zones, in decreasing
650 * priority.
651 *
Paul Jackson9276b1bc2006-12-06 20:31:48 -0800652 * If zlcache_ptr is not NULL, then it is just the address of zlcache,
653 * as explained above. If zlcache_ptr is NULL, there is no zlcache.
Mel Gormandd1a2392008-04-28 02:12:17 -0700654 * *
655 * To speed the reading of the zonelist, the zonerefs contain the zone index
656 * of the entry being read. Helper functions to access information given
657 * a struct zoneref are
658 *
659 * zonelist_zone() - Return the struct zone * for an entry in _zonerefs
660 * zonelist_zone_idx() - Return the index of the zone for an entry
661 * zonelist_node_idx() - Return the index of the node for an entry
Linus Torvalds1da177e2005-04-16 15:20:36 -0700662 */
663struct zonelist {
Paul Jackson9276b1bc2006-12-06 20:31:48 -0800664 struct zonelist_cache *zlcache_ptr; // NULL or &zlcache
Mel Gormandd1a2392008-04-28 02:12:17 -0700665 struct zoneref _zonerefs[MAX_ZONES_PER_ZONELIST + 1];
Paul Jackson9276b1bc2006-12-06 20:31:48 -0800666#ifdef CONFIG_NUMA
667 struct zonelist_cache zlcache; // optional ...
668#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669};
670
Tejun Heo0ee332c2011-12-08 10:22:09 -0800671#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
Mel Gormanc7132162006-09-27 01:49:43 -0700672struct node_active_region {
673 unsigned long start_pfn;
674 unsigned long end_pfn;
675 int nid;
676};
Tejun Heo0ee332c2011-12-08 10:22:09 -0800677#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700678
Heiko Carstens5b99cd02006-09-27 01:50:01 -0700679#ifndef CONFIG_DISCONTIGMEM
680/* The array of struct pages - for discontigmem use pgdat->lmem_map */
681extern struct page *mem_map;
682#endif
683
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684/*
685 * The pg_data_t structure is used in machines with CONFIG_DISCONTIGMEM
686 * (mostly NUMA machines?) to denote a higher-level memory zone than the
687 * zone denotes.
688 *
689 * On NUMA machines, each NUMA node would have a pg_data_t to describe
690 * it's memory layout.
691 *
692 * Memory statistics and page replacement data structures are maintained on a
693 * per-zone basis.
694 */
695struct bootmem_data;
696typedef struct pglist_data {
697 struct zone node_zones[MAX_NR_ZONES];
Christoph Lameter523b9452007-10-16 01:25:37 -0700698 struct zonelist node_zonelists[MAX_ZONELISTS];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699 int nr_zones;
KAMEZAWA Hiroyuki52d4b9a2008-10-18 20:28:16 -0700700#ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701 struct page *node_mem_map;
Andrew Mortonc255a452012-07-31 16:43:02 -0700702#ifdef CONFIG_MEMCG
KAMEZAWA Hiroyuki52d4b9a2008-10-18 20:28:16 -0700703 struct page_cgroup *node_page_cgroup;
704#endif
Andy Whitcroftd41dee32005-06-23 00:07:54 -0700705#endif
Yinghai Lu08677212010-02-10 01:20:20 -0800706#ifndef CONFIG_NO_BOOTMEM
Linus Torvalds1da177e2005-04-16 15:20:36 -0700707 struct bootmem_data *bdata;
Yinghai Lu08677212010-02-10 01:20:20 -0800708#endif
Dave Hansen208d54e2005-10-29 18:16:52 -0700709#ifdef CONFIG_MEMORY_HOTPLUG
710 /*
711 * Must be held any time you expect node_start_pfn, node_present_pages
712 * or node_spanned_pages stay constant. Holding this will also
713 * guarantee that any pfn_valid() stays that way.
714 *
715 * Nests above zone->lock and zone->size_seqlock.
716 */
717 spinlock_t node_size_lock;
718#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719 unsigned long node_start_pfn;
720 unsigned long node_present_pages; /* total number of physical pages */
721 unsigned long node_spanned_pages; /* total size of physical page
722 range, including holes */
723 int node_id;
David Rientjes957f8222012-10-08 16:33:24 -0700724 nodemask_t reclaim_nodes; /* Nodes allowed to reclaim from */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725 wait_queue_head_t kswapd_wait;
Mel Gorman55150612012-07-31 16:44:35 -0700726 wait_queue_head_t pfmemalloc_wait;
Jiang Liud8adde12012-07-11 14:01:52 -0700727 struct task_struct *kswapd; /* Protected by lock_memory_hotplug() */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728 int kswapd_max_order;
Mel Gorman99504742011-01-13 15:46:20 -0800729 enum zone_type classzone_idx;
Andrea Arcangeli8177a422012-03-23 20:56:34 +0100730#ifdef CONFIG_NUMA_BALANCING
731 /*
732 * Lock serializing the per destination node AutoNUMA memory
733 * migration rate limiting data.
734 */
735 spinlock_t numabalancing_migrate_lock;
736
737 /* Rate limiting time interval */
738 unsigned long numabalancing_migrate_next_window;
739
740 /* Number of pages migrated during the rate limiting time interval */
741 unsigned long numabalancing_migrate_nr_pages;
742#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743} pg_data_t;
744
745#define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
746#define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)
Andy Whitcroftd41dee32005-06-23 00:07:54 -0700747#ifdef CONFIG_FLAT_NODE_MEM_MAP
Dave Hansen408fde82005-06-23 00:07:37 -0700748#define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr))
Andy Whitcroftd41dee32005-06-23 00:07:54 -0700749#else
750#define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr))
751#endif
Dave Hansen408fde82005-06-23 00:07:37 -0700752#define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753
KAMEZAWA Hiroyukic6830c22011-06-16 17:28:07 +0900754#define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)
755
756#define node_end_pfn(nid) ({\
757 pg_data_t *__pgdat = NODE_DATA(nid);\
758 __pgdat->node_start_pfn + __pgdat->node_spanned_pages;\
759})
760
Dave Hansen208d54e2005-10-29 18:16:52 -0700761#include <linux/memory_hotplug.h>
762
Haicheng Li4eaf3f62010-05-24 14:32:52 -0700763extern struct mutex zonelists_mutex;
Jiang Liu9adb62a2012-07-31 16:43:28 -0700764void build_all_zonelists(pg_data_t *pgdat, struct zone *zone);
Mel Gorman99504742011-01-13 15:46:20 -0800765void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx);
Mel Gorman88f5acf2011-01-13 15:45:41 -0800766bool zone_watermark_ok(struct zone *z, int order, unsigned long mark,
767 int classzone_idx, int alloc_flags);
768bool zone_watermark_ok_safe(struct zone *z, int order, unsigned long mark,
Rohit Seth7fb1d9f2005-11-13 16:06:43 -0800769 int classzone_idx, int alloc_flags);
Dave Hansena2f3aa022007-01-10 23:15:30 -0800770enum memmap_context {
771 MEMMAP_EARLY,
772 MEMMAP_HOTPLUG,
773};
Yasunori Goto718127c2006-06-23 02:03:10 -0700774extern int init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,
Dave Hansena2f3aa022007-01-10 23:15:30 -0800775 unsigned long size,
776 enum memmap_context context);
Yasunori Goto718127c2006-06-23 02:03:10 -0700777
Hugh Dickinsbea8c152012-11-16 14:14:54 -0800778extern void lruvec_init(struct lruvec *lruvec);
Konstantin Khlebnikov7f5e86c2012-05-29 15:06:58 -0700779
780static inline struct zone *lruvec_zone(struct lruvec *lruvec)
781{
Andrew Mortonc255a452012-07-31 16:43:02 -0700782#ifdef CONFIG_MEMCG
Konstantin Khlebnikov7f5e86c2012-05-29 15:06:58 -0700783 return lruvec->zone;
784#else
785 return container_of(lruvec, struct zone, lruvec);
786#endif
787}
788
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789#ifdef CONFIG_HAVE_MEMORY_PRESENT
790void memory_present(int nid, unsigned long start, unsigned long end);
791#else
792static inline void memory_present(int nid, unsigned long start, unsigned long end) {}
793#endif
794
Lee Schermerhorn7aac7892010-05-26 14:45:00 -0700795#ifdef CONFIG_HAVE_MEMORYLESS_NODES
796int local_memory_node(int node_id);
797#else
798static inline int local_memory_node(int node_id) { return node_id; };
799#endif
800
Linus Torvalds1da177e2005-04-16 15:20:36 -0700801#ifdef CONFIG_NEED_NODE_MEMMAP_SIZE
802unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
803#endif
804
805/*
806 * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
807 */
808#define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
809
Con Kolivasf3fe6512006-01-06 00:11:15 -0800810static inline int populated_zone(struct zone *zone)
811{
812 return (!!zone->present_pages);
813}
814
Mel Gorman2a1e2742007-07-17 04:03:12 -0700815extern int movable_zone;
816
817static inline int zone_movable_is_highmem(void)
818{
Rabin Vincentfe030252012-07-31 16:43:14 -0700819#if defined(CONFIG_HIGHMEM) && defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP)
Mel Gorman2a1e2742007-07-17 04:03:12 -0700820 return movable_zone == ZONE_HIGHMEM;
821#else
822 return 0;
823#endif
824}
825
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700826static inline int is_highmem_idx(enum zone_type idx)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827{
Christoph Lametere53ef382006-09-25 23:31:14 -0700828#ifdef CONFIG_HIGHMEM
Mel Gorman2a1e2742007-07-17 04:03:12 -0700829 return (idx == ZONE_HIGHMEM ||
830 (idx == ZONE_MOVABLE && zone_movable_is_highmem()));
Christoph Lametere53ef382006-09-25 23:31:14 -0700831#else
832 return 0;
833#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834}
835
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700836static inline int is_normal_idx(enum zone_type idx)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700837{
838 return (idx == ZONE_NORMAL);
839}
Nick Piggin9328b8f2006-01-06 00:11:10 -0800840
Linus Torvalds1da177e2005-04-16 15:20:36 -0700841/**
842 * is_highmem - helper function to quickly check if a struct zone is a
843 * highmem zone or not. This is an attempt to keep references
844 * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
845 * @zone - pointer to struct zone variable
846 */
847static inline int is_highmem(struct zone *zone)
848{
Christoph Lametere53ef382006-09-25 23:31:14 -0700849#ifdef CONFIG_HIGHMEM
Harvey Harrisonddc81ed2008-04-28 02:12:07 -0700850 int zone_off = (char *)zone - (char *)zone->zone_pgdat->node_zones;
851 return zone_off == ZONE_HIGHMEM * sizeof(*zone) ||
852 (zone_off == ZONE_MOVABLE * sizeof(*zone) &&
853 zone_movable_is_highmem());
Christoph Lametere53ef382006-09-25 23:31:14 -0700854#else
855 return 0;
856#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857}
858
859static inline int is_normal(struct zone *zone)
860{
861 return zone == zone->zone_pgdat->node_zones + ZONE_NORMAL;
862}
863
Nick Piggin9328b8f2006-01-06 00:11:10 -0800864static inline int is_dma32(struct zone *zone)
865{
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700866#ifdef CONFIG_ZONE_DMA32
Nick Piggin9328b8f2006-01-06 00:11:10 -0800867 return zone == zone->zone_pgdat->node_zones + ZONE_DMA32;
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700868#else
869 return 0;
870#endif
Nick Piggin9328b8f2006-01-06 00:11:10 -0800871}
872
873static inline int is_dma(struct zone *zone)
874{
Christoph Lameter4b51d662007-02-10 01:43:10 -0800875#ifdef CONFIG_ZONE_DMA
Nick Piggin9328b8f2006-01-06 00:11:10 -0800876 return zone == zone->zone_pgdat->node_zones + ZONE_DMA;
Christoph Lameter4b51d662007-02-10 01:43:10 -0800877#else
878 return 0;
879#endif
Nick Piggin9328b8f2006-01-06 00:11:10 -0800880}
881
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882/* These two functions are used to setup the per zone pages min values */
883struct ctl_table;
Alexey Dobriyan8d65af72009-09-23 15:57:19 -0700884int min_free_kbytes_sysctl_handler(struct ctl_table *, int,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700885 void __user *, size_t *, loff_t *);
886extern int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1];
Alexey Dobriyan8d65af72009-09-23 15:57:19 -0700887int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *, int,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700888 void __user *, size_t *, loff_t *);
Alexey Dobriyan8d65af72009-09-23 15:57:19 -0700889int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *, int,
Rohit Seth8ad4b1f2006-01-08 01:00:40 -0800890 void __user *, size_t *, loff_t *);
Christoph Lameter96146342006-07-03 00:24:13 -0700891int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *, int,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -0700892 void __user *, size_t *, loff_t *);
Christoph Lameter0ff38492006-09-25 23:31:52 -0700893int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *, int,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -0700894 void __user *, size_t *, loff_t *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -0700896extern int numa_zonelist_order_handler(struct ctl_table *, int,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -0700897 void __user *, size_t *, loff_t *);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -0700898extern char numa_zonelist_order[];
899#define NUMA_ZONELIST_ORDER_LEN 16 /* string buffer size */
900
Dave Hansen93b75042005-06-23 00:07:47 -0700901#ifndef CONFIG_NEED_MULTIPLE_NODES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700902
903extern struct pglist_data contig_page_data;
904#define NODE_DATA(nid) (&contig_page_data)
905#define NODE_MEM_MAP(nid) mem_map
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906
Dave Hansen93b75042005-06-23 00:07:47 -0700907#else /* CONFIG_NEED_MULTIPLE_NODES */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700908
909#include <asm/mmzone.h>
910
Dave Hansen93b75042005-06-23 00:07:47 -0700911#endif /* !CONFIG_NEED_MULTIPLE_NODES */
Dave Hansen348f8b62005-06-23 00:07:40 -0700912
KAMEZAWA Hiroyuki95144c72006-03-27 01:16:02 -0800913extern struct pglist_data *first_online_pgdat(void);
914extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat);
915extern struct zone *next_zone(struct zone *zone);
KAMEZAWA Hiroyuki8357f862006-03-27 01:15:57 -0800916
917/**
Fernando Luis Vazquez Cao12d15f02008-05-23 13:05:01 -0700918 * for_each_online_pgdat - helper macro to iterate over all online nodes
KAMEZAWA Hiroyuki8357f862006-03-27 01:15:57 -0800919 * @pgdat - pointer to a pg_data_t variable
920 */
921#define for_each_online_pgdat(pgdat) \
922 for (pgdat = first_online_pgdat(); \
923 pgdat; \
924 pgdat = next_online_pgdat(pgdat))
KAMEZAWA Hiroyuki8357f862006-03-27 01:15:57 -0800925/**
926 * for_each_zone - helper macro to iterate over all memory zones
927 * @zone - pointer to struct zone variable
928 *
929 * The user only needs to declare the zone variable, for_each_zone
930 * fills it in.
931 */
932#define for_each_zone(zone) \
933 for (zone = (first_online_pgdat())->node_zones; \
934 zone; \
935 zone = next_zone(zone))
936
KOSAKI Motohiroee99c712009-03-31 15:19:31 -0700937#define for_each_populated_zone(zone) \
938 for (zone = (first_online_pgdat())->node_zones; \
939 zone; \
940 zone = next_zone(zone)) \
941 if (!populated_zone(zone)) \
942 ; /* do nothing */ \
943 else
944
Mel Gormandd1a2392008-04-28 02:12:17 -0700945static inline struct zone *zonelist_zone(struct zoneref *zoneref)
946{
947 return zoneref->zone;
948}
949
950static inline int zonelist_zone_idx(struct zoneref *zoneref)
951{
952 return zoneref->zone_idx;
953}
954
955static inline int zonelist_node_idx(struct zoneref *zoneref)
956{
957#ifdef CONFIG_NUMA
958 /* zone_to_nid not available in this context */
959 return zoneref->zone->node;
960#else
961 return 0;
962#endif /* CONFIG_NUMA */
963}
964
Mel Gorman19770b32008-04-28 02:12:18 -0700965/**
966 * 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
967 * @z - The cursor used as a starting point for the search
968 * @highest_zoneidx - The zone index of the highest zone to return
969 * @nodes - An optional nodemask to filter the zonelist with
970 * @zone - The first suitable zone found is returned via this parameter
971 *
972 * This function returns the next zone at or below a given zone index that is
973 * within the allowed nodemask using a cursor as the starting point for the
Mel Gorman5bead2a2008-09-13 02:33:19 -0700974 * search. The zoneref returned is a cursor that represents the current zone
975 * being examined. It should be advanced by one before calling
976 * next_zones_zonelist again.
Mel Gorman19770b32008-04-28 02:12:18 -0700977 */
978struct zoneref *next_zones_zonelist(struct zoneref *z,
979 enum zone_type highest_zoneidx,
980 nodemask_t *nodes,
981 struct zone **zone);
Mel Gormandd1a2392008-04-28 02:12:17 -0700982
Mel Gorman19770b32008-04-28 02:12:18 -0700983/**
984 * first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nodemask in a zonelist
985 * @zonelist - The zonelist to search for a suitable zone
986 * @highest_zoneidx - The zone index of the highest zone to return
987 * @nodes - An optional nodemask to filter the zonelist with
988 * @zone - The first suitable zone found is returned via this parameter
989 *
990 * This function returns the first zone at or below a given zone index that is
991 * within the allowed nodemask. The zoneref returned is a cursor that can be
Mel Gorman5bead2a2008-09-13 02:33:19 -0700992 * used to iterate the zonelist with next_zones_zonelist by advancing it by
993 * one before calling.
Mel Gorman19770b32008-04-28 02:12:18 -0700994 */
Mel Gormandd1a2392008-04-28 02:12:17 -0700995static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist,
Mel Gorman19770b32008-04-28 02:12:18 -0700996 enum zone_type highest_zoneidx,
997 nodemask_t *nodes,
998 struct zone **zone)
Mel Gorman54a6eb52008-04-28 02:12:16 -0700999{
Mel Gorman19770b32008-04-28 02:12:18 -07001000 return next_zones_zonelist(zonelist->_zonerefs, highest_zoneidx, nodes,
1001 zone);
Mel Gorman54a6eb52008-04-28 02:12:16 -07001002}
1003
Mel Gorman19770b32008-04-28 02:12:18 -07001004/**
1005 * 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
1006 * @zone - The current zone in the iterator
1007 * @z - The current pointer within zonelist->zones being iterated
1008 * @zlist - The zonelist being iterated
1009 * @highidx - The zone index of the highest zone to return
1010 * @nodemask - Nodemask allowed by the allocator
1011 *
1012 * This iterator iterates though all zones at or below a given zone index and
1013 * within a given nodemask
1014 */
1015#define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
1016 for (z = first_zones_zonelist(zlist, highidx, nodemask, &zone); \
1017 zone; \
Mel Gorman5bead2a2008-09-13 02:33:19 -07001018 z = next_zones_zonelist(++z, highidx, nodemask, &zone)) \
Mel Gorman54a6eb52008-04-28 02:12:16 -07001019
1020/**
1021 * for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index
1022 * @zone - The current zone in the iterator
1023 * @z - The current pointer within zonelist->zones being iterated
1024 * @zlist - The zonelist being iterated
1025 * @highidx - The zone index of the highest zone to return
1026 *
1027 * This iterator iterates though all zones at or below a given zone index.
1028 */
1029#define for_each_zone_zonelist(zone, z, zlist, highidx) \
Mel Gorman19770b32008-04-28 02:12:18 -07001030 for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)
Mel Gorman54a6eb52008-04-28 02:12:16 -07001031
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001032#ifdef CONFIG_SPARSEMEM
1033#include <asm/sparsemem.h>
1034#endif
1035
Mel Gormanc7132162006-09-27 01:49:43 -07001036#if !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) && \
Tejun Heo0ee332c2011-12-08 10:22:09 -08001037 !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP)
Andrew Mortonb4544562008-04-28 02:12:39 -07001038static inline unsigned long early_pfn_to_nid(unsigned long pfn)
1039{
1040 return 0;
1041}
Andy Whitcroftb159d432005-06-23 00:07:52 -07001042#endif
1043
Andy Whitcroft2bdaf112006-01-06 00:10:53 -08001044#ifdef CONFIG_FLATMEM
1045#define pfn_to_nid(pfn) (0)
1046#endif
1047
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001048#ifdef CONFIG_SPARSEMEM
1049
1050/*
1051 * SECTION_SHIFT #bits space required to store a section #
1052 *
1053 * PA_SECTION_SHIFT physical address to/from section number
1054 * PFN_SECTION_SHIFT pfn to/from section number
1055 */
1056#define SECTIONS_SHIFT (MAX_PHYSMEM_BITS - SECTION_SIZE_BITS)
1057
1058#define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
1059#define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)
1060
1061#define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
1062
1063#define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)
1064#define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))
1065
Mel Gorman835c1342007-10-16 01:25:47 -07001066#define SECTION_BLOCKFLAGS_BITS \
Mel Gormand9c23402007-10-16 01:26:01 -07001067 ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS)
Mel Gorman835c1342007-10-16 01:25:47 -07001068
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001069#if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
1070#error Allocator MAX_ORDER exceeds SECTION_SIZE
1071#endif
1072
Daniel Kipere3c40f32011-05-24 17:12:33 -07001073#define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
1074#define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
1075
Daniel Kipera539f352011-05-24 17:12:51 -07001076#define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)
1077#define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)
1078
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001079struct page;
KAMEZAWA Hiroyuki52d4b9a2008-10-18 20:28:16 -07001080struct page_cgroup;
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001081struct mem_section {
Andy Whitcroft29751f62005-06-23 00:08:00 -07001082 /*
1083 * This is, logically, a pointer to an array of struct
1084 * pages. However, it is stored with some other magic.
1085 * (see sparse.c::sparse_init_one_section())
1086 *
Andy Whitcroft30c253e2006-06-23 02:03:41 -07001087 * Additionally during early boot we encode node id of
1088 * the location of the section here to guide allocation.
1089 * (see sparse.c::memory_present())
1090 *
Andy Whitcroft29751f62005-06-23 00:08:00 -07001091 * Making it a UL at least makes someone do a cast
1092 * before using it wrong.
1093 */
1094 unsigned long section_mem_map;
Mel Gorman5c0e3062007-10-16 01:25:56 -07001095
1096 /* See declaration of similar field in struct zone */
1097 unsigned long *pageblock_flags;
Andrew Mortonc255a452012-07-31 16:43:02 -07001098#ifdef CONFIG_MEMCG
KAMEZAWA Hiroyuki52d4b9a2008-10-18 20:28:16 -07001099 /*
1100 * If !SPARSEMEM, pgdat doesn't have page_cgroup pointer. We use
1101 * section. (see memcontrol.h/page_cgroup.h about this.)
1102 */
1103 struct page_cgroup *page_cgroup;
1104 unsigned long pad;
1105#endif
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001106};
1107
Bob Picco3e347262005-09-03 15:54:28 -07001108#ifdef CONFIG_SPARSEMEM_EXTREME
1109#define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))
Bob Picco802f1922005-09-03 15:54:26 -07001110#else
Bob Picco3e347262005-09-03 15:54:28 -07001111#define SECTIONS_PER_ROOT 1
1112#endif
Bob Picco802f1922005-09-03 15:54:26 -07001113
Bob Picco3e347262005-09-03 15:54:28 -07001114#define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
Marcelo Roberto Jimenez0faa5632010-05-24 14:32:47 -07001115#define NR_SECTION_ROOTS DIV_ROUND_UP(NR_MEM_SECTIONS, SECTIONS_PER_ROOT)
Bob Picco3e347262005-09-03 15:54:28 -07001116#define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)
1117
1118#ifdef CONFIG_SPARSEMEM_EXTREME
1119extern struct mem_section *mem_section[NR_SECTION_ROOTS];
1120#else
1121extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
1122#endif
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001123
Andy Whitcroft29751f62005-06-23 00:08:00 -07001124static inline struct mem_section *__nr_to_section(unsigned long nr)
1125{
Bob Picco3e347262005-09-03 15:54:28 -07001126 if (!mem_section[SECTION_NR_TO_ROOT(nr)])
1127 return NULL;
1128 return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK];
Andy Whitcroft29751f62005-06-23 00:08:00 -07001129}
Dave Hansen4ca644d2005-10-29 18:16:51 -07001130extern int __section_nr(struct mem_section* ms);
Yasunori Goto04753272008-04-28 02:13:31 -07001131extern unsigned long usemap_size(void);
Andy Whitcroft29751f62005-06-23 00:08:00 -07001132
1133/*
1134 * We use the lower bits of the mem_map pointer to store
1135 * a little bit of information. There should be at least
1136 * 3 bits here due to 32-bit alignment.
1137 */
1138#define SECTION_MARKED_PRESENT (1UL<<0)
1139#define SECTION_HAS_MEM_MAP (1UL<<1)
1140#define SECTION_MAP_LAST_BIT (1UL<<2)
1141#define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1))
Andy Whitcroft30c253e2006-06-23 02:03:41 -07001142#define SECTION_NID_SHIFT 2
Andy Whitcroft29751f62005-06-23 00:08:00 -07001143
1144static inline struct page *__section_mem_map_addr(struct mem_section *section)
1145{
1146 unsigned long map = section->section_mem_map;
1147 map &= SECTION_MAP_MASK;
1148 return (struct page *)map;
1149}
1150
Andy Whitcroft540557b2007-10-16 01:24:11 -07001151static inline int present_section(struct mem_section *section)
Andy Whitcroft29751f62005-06-23 00:08:00 -07001152{
Bob Picco802f1922005-09-03 15:54:26 -07001153 return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));
Andy Whitcroft29751f62005-06-23 00:08:00 -07001154}
1155
Andy Whitcroft540557b2007-10-16 01:24:11 -07001156static inline int present_section_nr(unsigned long nr)
1157{
1158 return present_section(__nr_to_section(nr));
1159}
1160
1161static inline int valid_section(struct mem_section *section)
Andy Whitcroft29751f62005-06-23 00:08:00 -07001162{
Bob Picco802f1922005-09-03 15:54:26 -07001163 return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));
Andy Whitcroft29751f62005-06-23 00:08:00 -07001164}
1165
1166static inline int valid_section_nr(unsigned long nr)
1167{
1168 return valid_section(__nr_to_section(nr));
1169}
1170
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001171static inline struct mem_section *__pfn_to_section(unsigned long pfn)
1172{
Andy Whitcroft29751f62005-06-23 00:08:00 -07001173 return __nr_to_section(pfn_to_section_nr(pfn));
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001174}
1175
Will Deacon7b7bf492011-05-19 13:21:14 +01001176#ifndef CONFIG_HAVE_ARCH_PFN_VALID
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001177static inline int pfn_valid(unsigned long pfn)
1178{
1179 if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
1180 return 0;
Andy Whitcroft29751f62005-06-23 00:08:00 -07001181 return valid_section(__nr_to_section(pfn_to_section_nr(pfn)));
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001182}
Will Deacon7b7bf492011-05-19 13:21:14 +01001183#endif
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001184
Andy Whitcroft540557b2007-10-16 01:24:11 -07001185static inline int pfn_present(unsigned long pfn)
1186{
1187 if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
1188 return 0;
1189 return present_section(__nr_to_section(pfn_to_section_nr(pfn)));
1190}
1191
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001192/*
1193 * These are _only_ used during initialisation, therefore they
1194 * can use __initdata ... They could have names to indicate
1195 * this restriction.
1196 */
1197#ifdef CONFIG_NUMA
Andy Whitcroft161599f2006-01-06 00:10:54 -08001198#define pfn_to_nid(pfn) \
1199({ \
1200 unsigned long __pfn_to_nid_pfn = (pfn); \
1201 page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \
1202})
Andy Whitcroft2bdaf112006-01-06 00:10:53 -08001203#else
1204#define pfn_to_nid(pfn) (0)
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001205#endif
1206
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001207#define early_pfn_valid(pfn) pfn_valid(pfn)
1208void sparse_init(void);
1209#else
1210#define sparse_init() do {} while (0)
Dave Hansen28ae55c2005-09-03 15:54:29 -07001211#define sparse_index_init(_sec, _nid) do {} while (0)
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001212#endif /* CONFIG_SPARSEMEM */
1213
Andy Whitcroft75167952006-10-21 10:24:14 -07001214#ifdef CONFIG_NODES_SPAN_OTHER_NODES
KAMEZAWA Hiroyukicc2559b2009-02-18 14:48:33 -08001215bool early_pfn_in_nid(unsigned long pfn, int nid);
Andy Whitcroft75167952006-10-21 10:24:14 -07001216#else
1217#define early_pfn_in_nid(pfn, nid) (1)
1218#endif
1219
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001220#ifndef early_pfn_valid
1221#define early_pfn_valid(pfn) (1)
1222#endif
1223
1224void memory_present(int nid, unsigned long start, unsigned long end);
1225unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
1226
Andy Whitcroft14e07292007-05-06 14:49:14 -07001227/*
1228 * If it is possible to have holes within a MAX_ORDER_NR_PAGES, then we
1229 * need to check pfn validility within that MAX_ORDER_NR_PAGES block.
1230 * pfn_valid_within() should be used in this case; we optimise this away
1231 * when we have no holes within a MAX_ORDER_NR_PAGES block.
1232 */
1233#ifdef CONFIG_HOLES_IN_ZONE
1234#define pfn_valid_within(pfn) pfn_valid(pfn)
1235#else
1236#define pfn_valid_within(pfn) (1)
1237#endif
1238
Mel Gormaneb335752009-05-13 17:34:48 +01001239#ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
1240/*
1241 * pfn_valid() is meant to be able to tell if a given PFN has valid memmap
1242 * associated with it or not. In FLATMEM, it is expected that holes always
1243 * have valid memmap as long as there is valid PFNs either side of the hole.
1244 * In SPARSEMEM, it is assumed that a valid section has a memmap for the
1245 * entire section.
1246 *
1247 * However, an ARM, and maybe other embedded architectures in the future
1248 * free memmap backing holes to save memory on the assumption the memmap is
1249 * never used. The page_zone linkages are then broken even though pfn_valid()
1250 * returns true. A walker of the full memmap must then do this additional
1251 * check to ensure the memmap they are looking at is sane by making sure
1252 * the zone and PFN linkages are still valid. This is expensive, but walkers
1253 * of the full memmap are extremely rare.
1254 */
1255int memmap_valid_within(unsigned long pfn,
1256 struct page *page, struct zone *zone);
1257#else
1258static inline int memmap_valid_within(unsigned long pfn,
1259 struct page *page, struct zone *zone)
1260{
1261 return 1;
1262}
1263#endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
1264
Christoph Lameter97965472008-04-28 02:12:54 -07001265#endif /* !__GENERATING_BOUNDS.H */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001266#endif /* !__ASSEMBLY__ */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001267#endif /* _LINUX_MMZONE_H */