path: root/mm/page_alloc.c (plain)
blob: 9711cb8ba13cab94f5f31b49b651e1dfcb67a542

1	/*
2	* linux/mm/page_alloc.c
3	*
4	* Manages the free list, the system allocates free pages here.
5	* Note that kmalloc() lives in slab.c
6	*
7	* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
8	* Swap reorganised 29.12.95, Stephen Tweedie
9	* Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
10	* Reshaped it to be a zoned allocator, Ingo Molnar, Red Hat, 1999
11	* Discontiguous memory support, Kanoj Sarcar, SGI, Nov 1999
12	* Zone balancing, Kanoj Sarcar, SGI, Jan 2000
13	* Per cpu hot/cold page lists, bulk allocation, Martin J. Bligh, Sept 2002
14	* (lots of bits borrowed from Ingo Molnar & Andrew Morton)
15	*/
16
17	#include <linux/stddef.h>
18	#include <linux/mm.h>
19	#include <linux/swap.h>
20	#include <linux/interrupt.h>
21	#include <linux/pagemap.h>
22	#include <linux/jiffies.h>
23	#include <linux/bootmem.h>
24	#include <linux/memblock.h>
25	#include <linux/compiler.h>
26	#include <linux/kernel.h>
27	#include <linux/kmemcheck.h>
28	#include <linux/kasan.h>
29	#include <linux/module.h>
30	#include <linux/suspend.h>
31	#include <linux/pagevec.h>
32	#include <linux/blkdev.h>
33	#include <linux/slab.h>
34	#include <linux/ratelimit.h>
35	#include <linux/oom.h>
36	#include <linux/notifier.h>
37	#include <linux/topology.h>
38	#include <linux/sysctl.h>
39	#include <linux/cpu.h>
40	#include <linux/cpuset.h>
41	#include <linux/memory_hotplug.h>
42	#include <linux/nodemask.h>
43	#include <linux/vmalloc.h>
44	#include <linux/vmstat.h>
45	#include <linux/mempolicy.h>
46	#include <linux/memremap.h>
47	#include <linux/stop_machine.h>
48	#include <linux/sort.h>
49	#include <linux/pfn.h>
50	#include <linux/backing-dev.h>
51	#include <linux/fault-inject.h>
52	#include <linux/page-isolation.h>
53	#include <linux/page_ext.h>
54	#include <linux/debugobjects.h>
55	#include <linux/kmemleak.h>
56	#include <linux/compaction.h>
57	#include <trace/events/kmem.h>
58	#include <linux/prefetch.h>
59	#include <linux/mm_inline.h>
60	#include <linux/migrate.h>
61	#include <linux/page_ext.h>
62	#include <linux/hugetlb.h>
63	#include <linux/sched/rt.h>
64	#include <linux/page_owner.h>
65	#include <linux/kthread.h>
66	#include <linux/memcontrol.h>
67	#include <linux/psi.h>
68	#ifdef CONFIG_AMLOGIC_PAGE_TRACE
69	#include <linux/amlogic/page_trace.h>
70	#endif /* CONFIG_AMLOGIC_PAGE_TRACE */
71
72	#include <asm/sections.h>
73	#include <asm/tlbflush.h>
74	#include <asm/div64.h>
75	#include "internal.h"
76
77	/* prevent >1 _updater_ of zone percpu pageset ->high and ->batch fields */
78	static DEFINE_MUTEX(pcp_batch_high_lock);
79	#define MIN_PERCPU_PAGELIST_FRACTION (8)
80
81	#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
82	DEFINE_PER_CPU(int, numa_node);
83	EXPORT_PER_CPU_SYMBOL(numa_node);
84	#endif
85
86	#ifdef CONFIG_HAVE_MEMORYLESS_NODES
87	/*
88	* N.B., Do NOT reference the '_numa_mem_' per cpu variable directly.
89	* It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined.
90	* Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem()
91	* defined in <linux/topology.h>.
92	*/
93	DEFINE_PER_CPU(int, _numa_mem_); /* Kernel "local memory" node */
94	EXPORT_PER_CPU_SYMBOL(_numa_mem_);
95	int _node_numa_mem_[MAX_NUMNODES];
96	#endif
97
98	#ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY
99	volatile unsigned long latent_entropy __latent_entropy;
100	EXPORT_SYMBOL(latent_entropy);
101	#endif
102
103	/*
104	* Array of node states.
105	*/
106	nodemask_t node_states[NR_NODE_STATES] __read_mostly = {
107	[N_POSSIBLE] = NODE_MASK_ALL,
108	[N_ONLINE] = { { [0] = 1UL } },
109	#ifndef CONFIG_NUMA
110	[N_NORMAL_MEMORY] = { { [0] = 1UL } },
111	#ifdef CONFIG_HIGHMEM
112	[N_HIGH_MEMORY] = { { [0] = 1UL } },
113	#endif
114	#ifdef CONFIG_MOVABLE_NODE
115	[N_MEMORY] = { { [0] = 1UL } },
116	#endif
117	[N_CPU] = { { [0] = 1UL } },
118	#endif /* NUMA */
119	};
120	EXPORT_SYMBOL(node_states);
121
122	/* Protect totalram_pages and zone->managed_pages */
123	static DEFINE_SPINLOCK(managed_page_count_lock);
124
125	unsigned long totalram_pages __read_mostly;
126	unsigned long totalreserve_pages __read_mostly;
127	unsigned long totalcma_pages __read_mostly;
128
129	int percpu_pagelist_fraction;
130	gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK;
131
132	/*
133	* A cached value of the page's pageblock's migratetype, used when the page is
134	* put on a pcplist. Used to avoid the pageblock migratetype lookup when
135	* freeing from pcplists in most cases, at the cost of possibly becoming stale.
136	* Also the migratetype set in the page does not necessarily match the pcplist
137	* index, e.g. page might have MIGRATE_CMA set but be on a pcplist with any
138	* other index - this ensures that it will be put on the correct CMA freelist.
139	*/
140	static inline int get_pcppage_migratetype(struct page *page)
141	{
142	return page->index;
143	}
144
145	static inline void set_pcppage_migratetype(struct page *page, int migratetype)
146	{
147	page->index = migratetype;
148	}
149
150	#ifdef CONFIG_PM_SLEEP
151	/*
152	* The following functions are used by the suspend/hibernate code to temporarily
153	* change gfp_allowed_mask in order to avoid using I/O during memory allocations
154	* while devices are suspended. To avoid races with the suspend/hibernate code,
155	* they should always be called with pm_mutex held (gfp_allowed_mask also should
156	* only be modified with pm_mutex held, unless the suspend/hibernate code is
157	* guaranteed not to run in parallel with that modification).
158	*/
159
160	static gfp_t saved_gfp_mask;
161
162	void pm_restore_gfp_mask(void)
163	{
164	WARN_ON(!mutex_is_locked(&pm_mutex));
165	if (saved_gfp_mask) {
166	gfp_allowed_mask = saved_gfp_mask;
167	saved_gfp_mask = 0;
168	}
169	}
170
171	void pm_restrict_gfp_mask(void)
172	{
173	WARN_ON(!mutex_is_locked(&pm_mutex));
174	WARN_ON(saved_gfp_mask);
175	saved_gfp_mask = gfp_allowed_mask;
176	gfp_allowed_mask &= ~(__GFP_IO | __GFP_FS);
177	}
178
179	bool pm_suspended_storage(void)
180	{
181	if ((gfp_allowed_mask & (__GFP_IO | __GFP_FS)) == (__GFP_IO | __GFP_FS))
182	return false;
183	return true;
184	}
185	#endif /* CONFIG_PM_SLEEP */
186
187	#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
188	unsigned int pageblock_order __read_mostly;
189	#endif
190
191	static void __free_pages_ok(struct page *page, unsigned int order);
192
193	/*
194	* results with 256, 32 in the lowmem_reserve sysctl:
195	* 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
196	* 1G machine -> (16M dma, 784M normal, 224M high)
197	* NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
198	* HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
199	* HIGHMEM allocation will leave (224M+784M)/256 of ram reserved in ZONE_DMA
200	*
201	* TBD: should special case ZONE_DMA32 machines here - in those we normally
202	* don't need any ZONE_NORMAL reservation
203	*/
204	int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = {
205	#ifdef CONFIG_ZONE_DMA
206	256,
207	#endif
208	#ifdef CONFIG_ZONE_DMA32
209	256,
210	#endif
211	#ifdef CONFIG_HIGHMEM
212	32,
213	#endif
214	32,
215	};
216
217	EXPORT_SYMBOL(totalram_pages);
218
219	static char * const zone_names[MAX_NR_ZONES] = {
220	#ifdef CONFIG_ZONE_DMA
221	"DMA",
222	#endif
223	#ifdef CONFIG_ZONE_DMA32
224	"DMA32",
225	#endif
226	"Normal",
227	#ifdef CONFIG_HIGHMEM
228	"HighMem",
229	#endif
230	"Movable",
231	#ifdef CONFIG_ZONE_DEVICE
232	"Device",
233	#endif
234	};
235
236	char * const migratetype_names[MIGRATE_TYPES] = {
237	"Unmovable",
238	"Movable",
239	"Reclaimable",
240	"HighAtomic",
241	#ifdef CONFIG_CMA
242	"CMA",
243	#endif
244	#ifdef CONFIG_MEMORY_ISOLATION
245	"Isolate",
246	#endif
247	};
248
249	compound_page_dtor * const compound_page_dtors[] = {
250	NULL,
251	free_compound_page,
252	#ifdef CONFIG_HUGETLB_PAGE
253	free_huge_page,
254	#endif
255	#ifdef CONFIG_TRANSPARENT_HUGEPAGE
256	free_transhuge_page,
257	#endif
258	};
259
260	/*
261	* Try to keep at least this much lowmem free. Do not allow normal
262	* allocations below this point, only high priority ones. Automatically
263	* tuned according to the amount of memory in the system.
264	*/
265	int min_free_kbytes = 1024;
266	int user_min_free_kbytes = -1;
267	int watermark_scale_factor = 10;
268
269	/*
270	* Extra memory for the system to try freeing. Used to temporarily
271	* free memory, to make space for new workloads. Anyone can allocate
272	* down to the min watermarks controlled by min_free_kbytes above.
273	*/
274	int extra_free_kbytes = 0;
275
276	static unsigned long __meminitdata nr_kernel_pages;
277	static unsigned long __meminitdata nr_all_pages;
278	static unsigned long __meminitdata dma_reserve;
279
280	#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
281	static unsigned long __meminitdata arch_zone_lowest_possible_pfn[MAX_NR_ZONES];
282	static unsigned long __meminitdata arch_zone_highest_possible_pfn[MAX_NR_ZONES];
283	static unsigned long __initdata required_kernelcore;
284	static unsigned long __initdata required_movablecore;
285	static unsigned long __meminitdata zone_movable_pfn[MAX_NUMNODES];
286	static bool mirrored_kernelcore;
287
288	/* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
289	int movable_zone;
290	EXPORT_SYMBOL(movable_zone);
291	#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
292
293	#if MAX_NUMNODES > 1
294	int nr_node_ids __read_mostly = MAX_NUMNODES;
295	int nr_online_nodes __read_mostly = 1;
296	EXPORT_SYMBOL(nr_node_ids);
297	EXPORT_SYMBOL(nr_online_nodes);
298	#endif
299
300	int page_group_by_mobility_disabled __read_mostly;
301
302	#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
303
304	/*
305	* Determine how many pages need to be initialized durig early boot
306	* (non-deferred initialization).
307	* The value of first_deferred_pfn will be set later, once non-deferred pages
308	* are initialized, but for now set it ULONG_MAX.
309	*/
310	static inline void reset_deferred_meminit(pg_data_t *pgdat)
311	{
312	phys_addr_t start_addr, end_addr;
313	unsigned long max_pgcnt;
314	unsigned long reserved;
315
316	/*
317	* Initialise at least 2G of a node but also take into account that
318	* two large system hashes that can take up 1GB for 0.25TB/node.
319	*/
320	max_pgcnt = max(2UL << (30 - PAGE_SHIFT),
321	(pgdat->node_spanned_pages >> 8));
322
323	/*
324	* Compensate the all the memblock reservations (e.g. crash kernel)
325	* from the initial estimation to make sure we will initialize enough
326	* memory to boot.
327	*/
328	start_addr = PFN_PHYS(pgdat->node_start_pfn);
329	end_addr = PFN_PHYS(pgdat->node_start_pfn + max_pgcnt);
330	reserved = memblock_reserved_memory_within(start_addr, end_addr);
331	max_pgcnt += PHYS_PFN(reserved);
332
333	pgdat->static_init_pgcnt = min(max_pgcnt, pgdat->node_spanned_pages);
334	pgdat->first_deferred_pfn = ULONG_MAX;
335	}
336
337	/* Returns true if the struct page for the pfn is uninitialised */
338	static inline bool __meminit early_page_uninitialised(unsigned long pfn)
339	{
340	int nid = early_pfn_to_nid(pfn);
341
342	if (node_online(nid) && pfn >= NODE_DATA(nid)->first_deferred_pfn)
343	return true;
344
345	return false;
346	}
347
348	/*
349	* Returns false when the remaining initialisation should be deferred until
350	* later in the boot cycle when it can be parallelised.
351	*/
352	static inline bool update_defer_init(pg_data_t *pgdat,
353	unsigned long pfn, unsigned long zone_end,
354	unsigned long *nr_initialised)
355	{
356	/* Always populate low zones for address-contrained allocations */
357	if (zone_end < pgdat_end_pfn(pgdat))
358	return true;
359	(*nr_initialised)++;
360	if ((*nr_initialised > pgdat->static_init_pgcnt) &&
361	(pfn & (PAGES_PER_SECTION - 1)) == 0) {
362	pgdat->first_deferred_pfn = pfn;
363	return false;
364	}
365
366	return true;
367	}
368	#else
369	static inline void reset_deferred_meminit(pg_data_t *pgdat)
370	{
371	}
372
373	static inline bool early_page_uninitialised(unsigned long pfn)
374	{
375	return false;
376	}
377
378	static inline bool update_defer_init(pg_data_t *pgdat,
379	unsigned long pfn, unsigned long zone_end,
380	unsigned long *nr_initialised)
381	{
382	return true;
383	}
384	#endif
385
386	/* Return a pointer to the bitmap storing bits affecting a block of pages */
387	static inline unsigned long *get_pageblock_bitmap(struct page *page,
388	unsigned long pfn)
389	{
390	#ifdef CONFIG_SPARSEMEM
391	return __pfn_to_section(pfn)->pageblock_flags;
392	#else
393	return page_zone(page)->pageblock_flags;
394	#endif /* CONFIG_SPARSEMEM */
395	}
396
397	static inline int pfn_to_bitidx(struct page *page, unsigned long pfn)
398	{
399	#ifdef CONFIG_SPARSEMEM
400	pfn &= (PAGES_PER_SECTION-1);
401	return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
402	#else
403	pfn = pfn - round_down(page_zone(page)->zone_start_pfn, pageblock_nr_pages);
404	return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
405	#endif /* CONFIG_SPARSEMEM */
406	}
407
408	/**
409	* get_pfnblock_flags_mask - Return the requested group of flags for the pageblock_nr_pages block of pages
410	* @page: The page within the block of interest
411	* @pfn: The target page frame number
412	* @end_bitidx: The last bit of interest to retrieve
413	* @mask: mask of bits that the caller is interested in
414	*
415	* Return: pageblock_bits flags
416	*/
417	static __always_inline unsigned long __get_pfnblock_flags_mask(struct page *page,
418	unsigned long pfn,
419	unsigned long end_bitidx,
420	unsigned long mask)
421	{
422	unsigned long *bitmap;
423	unsigned long bitidx, word_bitidx;
424	unsigned long word;
425
426	bitmap = get_pageblock_bitmap(page, pfn);
427	bitidx = pfn_to_bitidx(page, pfn);
428	word_bitidx = bitidx / BITS_PER_LONG;
429	bitidx &= (BITS_PER_LONG-1);
430
431	word = bitmap[word_bitidx];
432	bitidx += end_bitidx;
433	return (word >> (BITS_PER_LONG - bitidx - 1)) & mask;
434	}
435
436	unsigned long get_pfnblock_flags_mask(struct page *page, unsigned long pfn,
437	unsigned long end_bitidx,
438	unsigned long mask)
439	{
440	return __get_pfnblock_flags_mask(page, pfn, end_bitidx, mask);
441	}
442
443	static __always_inline int get_pfnblock_migratetype(struct page *page, unsigned long pfn)
444	{
445	return __get_pfnblock_flags_mask(page, pfn, PB_migrate_end, MIGRATETYPE_MASK);
446	}
447
448	/**
449	* set_pfnblock_flags_mask - Set the requested group of flags for a pageblock_nr_pages block of pages
450	* @page: The page within the block of interest
451	* @flags: The flags to set
452	* @pfn: The target page frame number
453	* @end_bitidx: The last bit of interest
454	* @mask: mask of bits that the caller is interested in
455	*/
456	void set_pfnblock_flags_mask(struct page *page, unsigned long flags,
457	unsigned long pfn,
458	unsigned long end_bitidx,
459	unsigned long mask)
460	{
461	unsigned long *bitmap;
462	unsigned long bitidx, word_bitidx;
463	unsigned long old_word, word;
464
465	BUILD_BUG_ON(NR_PAGEBLOCK_BITS != 4);
466
467	bitmap = get_pageblock_bitmap(page, pfn);
468	bitidx = pfn_to_bitidx(page, pfn);
469	word_bitidx = bitidx / BITS_PER_LONG;
470	bitidx &= (BITS_PER_LONG-1);
471
472	VM_BUG_ON_PAGE(!zone_spans_pfn(page_zone(page), pfn), page);
473
474	bitidx += end_bitidx;
475	mask <<= (BITS_PER_LONG - bitidx - 1);
476	flags <<= (BITS_PER_LONG - bitidx - 1);
477
478	word = READ_ONCE(bitmap[word_bitidx]);
479	for (;;) {
480	old_word = cmpxchg(&bitmap[word_bitidx], word, (word & ~mask) | flags);
481	if (word == old_word)
482	break;
483	word = old_word;
484	}
485	}
486
487	void set_pageblock_migratetype(struct page *page, int migratetype)
488	{
489	if (unlikely(page_group_by_mobility_disabled &&
490	migratetype < MIGRATE_PCPTYPES))
491	migratetype = MIGRATE_UNMOVABLE;
492
493	set_pageblock_flags_group(page, (unsigned long)migratetype,
494	PB_migrate, PB_migrate_end);
495	}
496
497	#ifdef CONFIG_DEBUG_VM
498	static int page_outside_zone_boundaries(struct zone *zone, struct page *page)
499	{
500	int ret = 0;
501	unsigned seq;
502	unsigned long pfn = page_to_pfn(page);
503	unsigned long sp, start_pfn;
504
505	do {
506	seq = zone_span_seqbegin(zone);
507	start_pfn = zone->zone_start_pfn;
508	sp = zone->spanned_pages;
509	if (!zone_spans_pfn(zone, pfn))
510	ret = 1;
511	} while (zone_span_seqretry(zone, seq));
512
513	if (ret)
514	pr_err("page 0x%lx outside node %d zone %s [ 0x%lx - 0x%lx ]\n",
515	pfn, zone_to_nid(zone), zone->name,
516	start_pfn, start_pfn + sp);
517
518	return ret;
519	}
520
521	static int page_is_consistent(struct zone *zone, struct page *page)
522	{
523	if (!pfn_valid_within(page_to_pfn(page)))
524	return 0;
525	if (zone != page_zone(page))
526	return 0;
527
528	return 1;
529	}
530	/*
531	* Temporary debugging check for pages not lying within a given zone.
532	*/
533	static int bad_range(struct zone *zone, struct page *page)
534	{
535	if (page_outside_zone_boundaries(zone, page))
536	return 1;
537	if (!page_is_consistent(zone, page))
538	return 1;
539
540	return 0;
541	}
542	#else
543	static inline int bad_range(struct zone *zone, struct page *page)
544	{
545	return 0;
546	}
547	#endif
548
549	static void bad_page(struct page *page, const char *reason,
550	unsigned long bad_flags)
551	{
552	static unsigned long resume;
553	static unsigned long nr_shown;
554	static unsigned long nr_unshown;
555
556	/*
557	* Allow a burst of 60 reports, then keep quiet for that minute;
558	* or allow a steady drip of one report per second.
559	*/
560	if (nr_shown == 60) {
561	if (time_before(jiffies, resume)) {
562	nr_unshown++;
563	goto out;
564	}
565	if (nr_unshown) {
566	pr_alert(
567	"BUG: Bad page state: %lu messages suppressed\n",
568	nr_unshown);
569	nr_unshown = 0;
570	}
571	nr_shown = 0;
572	}
573	if (nr_shown++ == 0)
574	resume = jiffies + 60 * HZ;
575
576	pr_alert("BUG: Bad page state in process %s pfn:%05lx\n",
577	current->comm, page_to_pfn(page));
578	__dump_page(page, reason);
579	bad_flags &= page->flags;
580	if (bad_flags)
581	pr_alert("bad because of flags: %#lx(%pGp)\n",
582	bad_flags, &bad_flags);
583	dump_page_owner(page);
584
585	print_modules();
586	dump_stack();
587	out:
588	/* Leave bad fields for debug, except PageBuddy could make trouble */
589	page_mapcount_reset(page); /* remove PageBuddy */
590	add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
591	}
592
593	/*
594	* Higher-order pages are called "compound pages". They are structured thusly:
595	*
596	* The first PAGE_SIZE page is called the "head page" and have PG_head set.
597	*
598	* The remaining PAGE_SIZE pages are called "tail pages". PageTail() is encoded
599	* in bit 0 of page->compound_head. The rest of bits is pointer to head page.
600	*
601	* The first tail page's ->compound_dtor holds the offset in array of compound
602	* page destructors. See compound_page_dtors.
603	*
604	* The first tail page's ->compound_order holds the order of allocation.
605	* This usage means that zero-order pages may not be compound.
606	*/
607
608	void free_compound_page(struct page *page)
609	{
610	__free_pages_ok(page, compound_order(page));
611	}
612
613	void prep_compound_page(struct page *page, unsigned int order)
614	{
615	int i;
616	int nr_pages = 1 << order;
617
618	set_compound_page_dtor(page, COMPOUND_PAGE_DTOR);
619	set_compound_order(page, order);
620	__SetPageHead(page);
621	for (i = 1; i < nr_pages; i++) {
622	struct page *p = page + i;
623	set_page_count(p, 0);
624	p->mapping = TAIL_MAPPING;
625	set_compound_head(p, page);
626	}
627	atomic_set(compound_mapcount_ptr(page), -1);
628	}
629
630	#ifdef CONFIG_DEBUG_PAGEALLOC
631	unsigned int _debug_guardpage_minorder;
632	bool _debug_pagealloc_enabled __read_mostly
633	= IS_ENABLED(CONFIG_DEBUG_PAGEALLOC_ENABLE_DEFAULT);
634	EXPORT_SYMBOL(_debug_pagealloc_enabled);
635	bool _debug_guardpage_enabled __read_mostly;
636
637	static int __init early_debug_pagealloc(char *buf)
638	{
639	if (!buf)
640	return -EINVAL;
641	return kstrtobool(buf, &_debug_pagealloc_enabled);
642	}
643	early_param("debug_pagealloc", early_debug_pagealloc);
644
645	static bool need_debug_guardpage(void)
646	{
647	/* If we don't use debug_pagealloc, we don't need guard page */
648	if (!debug_pagealloc_enabled())
649	return false;
650
651	if (!debug_guardpage_minorder())
652	return false;
653
654	return true;
655	}
656
657	static void init_debug_guardpage(void)
658	{
659	if (!debug_pagealloc_enabled())
660	return;
661
662	if (!debug_guardpage_minorder())
663	return;
664
665	_debug_guardpage_enabled = true;
666	}
667
668	struct page_ext_operations debug_guardpage_ops = {
669	.need = need_debug_guardpage,
670	.init = init_debug_guardpage,
671	};
672
673	static int __init debug_guardpage_minorder_setup(char *buf)
674	{
675	unsigned long res;
676
677	if (kstrtoul(buf, 10, &res) < 0 || res > MAX_ORDER / 2) {
678	pr_err("Bad debug_guardpage_minorder value\n");
679	return 0;
680	}
681	_debug_guardpage_minorder = res;
682	pr_info("Setting debug_guardpage_minorder to %lu\n", res);
683	return 0;
684	}
685	early_param("debug_guardpage_minorder", debug_guardpage_minorder_setup);
686
687	static inline bool set_page_guard(struct zone *zone, struct page *page,
688	unsigned int order, int migratetype)
689	{
690	struct page_ext *page_ext;
691
692	if (!debug_guardpage_enabled())
693	return false;
694
695	if (order >= debug_guardpage_minorder())
696	return false;
697
698	page_ext = lookup_page_ext(page);
699	if (unlikely(!page_ext))
700	return false;
701
702	__set_bit(PAGE_EXT_DEBUG_GUARD, &page_ext->flags);
703
704	INIT_LIST_HEAD(&page->lru);
705	set_page_private(page, order);
706	/* Guard pages are not available for any usage */
707	__mod_zone_freepage_state(zone, -(1 << order), migratetype);
708
709	return true;
710	}
711
712	static inline void clear_page_guard(struct zone *zone, struct page *page,
713	unsigned int order, int migratetype)
714	{
715	struct page_ext *page_ext;
716
717	if (!debug_guardpage_enabled())
718	return;
719
720	page_ext = lookup_page_ext(page);
721	if (unlikely(!page_ext))
722	return;
723
724	__clear_bit(PAGE_EXT_DEBUG_GUARD, &page_ext->flags);
725
726	set_page_private(page, 0);
727	if (!is_migrate_isolate(migratetype))
728	__mod_zone_freepage_state(zone, (1 << order), migratetype);
729	}
730	#else
731	struct page_ext_operations debug_guardpage_ops;
732	static inline bool set_page_guard(struct zone *zone, struct page *page,
733	unsigned int order, int migratetype) { return false; }
734	static inline void clear_page_guard(struct zone *zone, struct page *page,
735	unsigned int order, int migratetype) {}
736	#endif
737
738	static inline void set_page_order(struct page *page, unsigned int order)
739	{
740	set_page_private(page, order);
741	__SetPageBuddy(page);
742	}
743
744	static inline void rmv_page_order(struct page *page)
745	{
746	__ClearPageBuddy(page);
747	set_page_private(page, 0);
748	}
749
750	/*
751	* This function checks whether a page is free && is the buddy
752	* we can do coalesce a page and its buddy if
753	* (a) the buddy is not in a hole &&
754	* (b) the buddy is in the buddy system &&
755	* (c) a page and its buddy have the same order &&
756	* (d) a page and its buddy are in the same zone.
757	*
758	* For recording whether a page is in the buddy system, we set ->_mapcount
759	* PAGE_BUDDY_MAPCOUNT_VALUE.
760	* Setting, clearing, and testing _mapcount PAGE_BUDDY_MAPCOUNT_VALUE is
761	* serialized by zone->lock.
762	*
763	* For recording page's order, we use page_private(page).
764	*/
765	static inline int page_is_buddy(struct page *page, struct page *buddy,
766	unsigned int order)
767	{
768	if (!pfn_valid_within(page_to_pfn(buddy)))
769	return 0;
770
771	if (page_is_guard(buddy) && page_order(buddy) == order) {
772	if (page_zone_id(page) != page_zone_id(buddy))
773	return 0;
774
775	VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy);
776
777	return 1;
778	}
779
780	if (PageBuddy(buddy) && page_order(buddy) == order) {
781	/*
782	* zone check is done late to avoid uselessly
783	* calculating zone/node ids for pages that could
784	* never merge.
785	*/
786	if (page_zone_id(page) != page_zone_id(buddy))
787	return 0;
788
789	VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy);
790
791	return 1;
792	}
793	return 0;
794	}
795
796	/*
797	* Freeing function for a buddy system allocator.
798	*
799	* The concept of a buddy system is to maintain direct-mapped table
800	* (containing bit values) for memory blocks of various "orders".
801	* The bottom level table contains the map for the smallest allocatable
802	* units of memory (here, pages), and each level above it describes
803	* pairs of units from the levels below, hence, "buddies".
804	* At a high level, all that happens here is marking the table entry
805	* at the bottom level available, and propagating the changes upward
806	* as necessary, plus some accounting needed to play nicely with other
807	* parts of the VM system.
808	* At each level, we keep a list of pages, which are heads of continuous
809	* free pages of length of (1 << order) and marked with _mapcount
810	* PAGE_BUDDY_MAPCOUNT_VALUE. Page's order is recorded in page_private(page)
811	* field.
812	* So when we are allocating or freeing one, we can derive the state of the
813	* other. That is, if we allocate a small block, and both were
814	* free, the remainder of the region must be split into blocks.
815	* If a block is freed, and its buddy is also free, then this
816	* triggers coalescing into a block of larger size.
817	*
818	* -- nyc
819	*/
820
821	static inline void __free_one_page(struct page *page,
822	unsigned long pfn,
823	struct zone *zone, unsigned int order,
824	int migratetype)
825	{
826	unsigned long page_idx;
827	unsigned long combined_idx;
828	unsigned long uninitialized_var(buddy_idx);
829	struct page *buddy;
830	unsigned int max_order;
831	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
832	int buddy_mg;
833
834	migratetype = get_pageblock_migratetype(page);
835	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
836
837	max_order = min_t(unsigned int, MAX_ORDER, pageblock_order + 1);
838
839	VM_BUG_ON(!zone_is_initialized(zone));
840	VM_BUG_ON_PAGE(page->flags & PAGE_FLAGS_CHECK_AT_PREP, page);
841
842	VM_BUG_ON(migratetype == -1);
843	if (likely(!is_migrate_isolate(migratetype)))
844	__mod_zone_freepage_state(zone, 1 << order, migratetype);
845
846	page_idx = pfn & ((1 << MAX_ORDER) - 1);
847
848	VM_BUG_ON_PAGE(page_idx & ((1 << order) - 1), page);
849	VM_BUG_ON_PAGE(bad_range(zone, page), page);
850
851	continue_merging:
852	while (order < max_order - 1) {
853	buddy_idx = __find_buddy_index(page_idx, order);
854	buddy = page + (buddy_idx - page_idx);
855	if (!page_is_buddy(page, buddy, order))
856	goto done_merging;
857	/*
858	* Our buddy is free or it is CONFIG_DEBUG_PAGEALLOC guard page,
859	* merge with it and move up one order.
860	*/
861	if (page_is_guard(buddy)) {
862	clear_page_guard(zone, buddy, order, migratetype);
863	} else {
864	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
865	/*
866	* Kernel have provided some information about it in
867	* /proc/pagetypeinfo, /proc/buddyinfo. But both of them
868	* do not have a summary of free pages of each migrate
869	* type.
870	* Update zone free migrate type change according
871	* free_area's nr_free, this information is helpful and
872	* can be shown in echo m > /proc/sysrq-trigger.
873	*/
874	buddy_mg = get_pcppage_migratetype(buddy);
875	__mod_zone_migrate_state(zone, -(1 << order), buddy_mg);
876	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
877	list_del(&buddy->lru);
878	zone->free_area[order].nr_free--;
879	rmv_page_order(buddy);
880	}
881	combined_idx = buddy_idx & page_idx;
882	page = page + (combined_idx - page_idx);
883	page_idx = combined_idx;
884	order++;
885	}
886	if (max_order < MAX_ORDER) {
887	/* If we are here, it means order is >= pageblock_order.
888	* We want to prevent merge between freepages on isolate
889	* pageblock and normal pageblock. Without this, pageblock
890	* isolation could cause incorrect freepage or CMA accounting.
891	*
892	* We don't want to hit this code for the more frequent
893	* low-order merging.
894	*/
895	if (unlikely(has_isolate_pageblock(zone))) {
896	int buddy_mt;
897
898	buddy_idx = __find_buddy_index(page_idx, order);
899	buddy = page + (buddy_idx - page_idx);
900	buddy_mt = get_pageblock_migratetype(buddy);
901
902	if (migratetype != buddy_mt
903	&& (is_migrate_isolate(migratetype) ||
904	is_migrate_isolate(buddy_mt)))
905	goto done_merging;
906	}
907	max_order++;
908	goto continue_merging;
909	}
910
911	done_merging:
912	set_page_order(page, order);
913
914	/*
915	* If this is not the largest possible page, check if the buddy
916	* of the next-highest order is free. If it is, it's possible
917	* that pages are being freed that will coalesce soon. In case,
918	* that is happening, add the free page to the tail of the list
919	* so it's less likely to be used soon and more likely to be merged
920	* as a higher order page
921	*/
922	if ((order < MAX_ORDER-2) && pfn_valid_within(page_to_pfn(buddy))) {
923	struct page *higher_page, *higher_buddy;
924	combined_idx = buddy_idx & page_idx;
925	higher_page = page + (combined_idx - page_idx);
926	buddy_idx = __find_buddy_index(combined_idx, order + 1);
927	higher_buddy = higher_page + (buddy_idx - combined_idx);
928	if (page_is_buddy(higher_page, higher_buddy, order + 1)) {
929	list_add_tail(&page->lru,
930	&zone->free_area[order].free_list[migratetype]);
931	goto out;
932	}
933	}
934
935	#if defined(CONFIG_AMLOGIC_MEMORY_EXTEND) && defined(CONFIG_KASAN)
936	/*
937	* always put freed page to tail of buddy system, in
938	* order to increase probability of use-after-free
939	* for KASAN check.
940	*/
941	list_add_tail(&page->lru,
942	&zone->free_area[order].free_list[migratetype]);
943	#else
944	list_add(&page->lru, &zone->free_area[order].free_list[migratetype]);
945	#endif
946	out:
947	zone->free_area[order].nr_free++;
948	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
949	set_pcppage_migratetype(page, migratetype);
950	__mod_zone_migrate_state(zone, (1 << order), migratetype);
951	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
952	}
953
954	/*
955	* A bad page could be due to a number of fields. Instead of multiple branches,
956	* try and check multiple fields with one check. The caller must do a detailed
957	* check if necessary.
958	*/
959	static inline bool page_expected_state(struct page *page,
960	unsigned long check_flags)
961	{
962	if (unlikely(atomic_read(&page->_mapcount) != -1))
963	return false;
964
965	if (unlikely((unsigned long)page->mapping |
966	page_ref_count(page) |
967	#ifdef CONFIG_MEMCG
968	(unsigned long)page->mem_cgroup |
969	#endif
970	(page->flags & check_flags)))
971	return false;
972
973	return true;
974	}
975
976	static void free_pages_check_bad(struct page *page)
977	{
978	const char *bad_reason;
979	unsigned long bad_flags;
980
981	bad_reason = NULL;
982	bad_flags = 0;
983
984	if (unlikely(atomic_read(&page->_mapcount) != -1))
985	bad_reason = "nonzero mapcount";
986	if (unlikely(page->mapping != NULL))
987	bad_reason = "non-NULL mapping";
988	if (unlikely(page_ref_count(page) != 0))
989	bad_reason = "nonzero _refcount";
990	if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_FREE)) {
991	bad_reason = "PAGE_FLAGS_CHECK_AT_FREE flag(s) set";
992	bad_flags = PAGE_FLAGS_CHECK_AT_FREE;
993	}
994	#ifdef CONFIG_MEMCG
995	if (unlikely(page->mem_cgroup))
996	bad_reason = "page still charged to cgroup";
997	#endif
998	bad_page(page, bad_reason, bad_flags);
999	}
1000
1001	static inline int free_pages_check(struct page *page)
1002	{
1003	if (likely(page_expected_state(page, PAGE_FLAGS_CHECK_AT_FREE)))
1004	return 0;
1005
1006	/* Something has gone sideways, find it */
1007	free_pages_check_bad(page);
1008	return 1;
1009	}
1010
1011	static int free_tail_pages_check(struct page *head_page, struct page *page)
1012	{
1013	int ret = 1;
1014
1015	/*
1016	* We rely page->lru.next never has bit 0 set, unless the page
1017	* is PageTail(). Let's make sure that's true even for poisoned ->lru.
1018	*/
1019	BUILD_BUG_ON((unsigned long)LIST_POISON1 & 1);
1020
1021	if (!IS_ENABLED(CONFIG_DEBUG_VM)) {
1022	ret = 0;
1023	goto out;
1024	}
1025	switch (page - head_page) {
1026	case 1:
1027	/* the first tail page: ->mapping is compound_mapcount() */
1028	if (unlikely(compound_mapcount(page))) {
1029	bad_page(page, "nonzero compound_mapcount", 0);
1030	goto out;
1031	}
1032	break;
1033	case 2:
1034	/*
1035	* the second tail page: ->mapping is
1036	* page_deferred_list().next -- ignore value.
1037	*/
1038	break;
1039	default:
1040	if (page->mapping != TAIL_MAPPING) {
1041	bad_page(page, "corrupted mapping in tail page", 0);
1042	goto out;
1043	}
1044	break;
1045	}
1046	if (unlikely(!PageTail(page))) {
1047	bad_page(page, "PageTail not set", 0);
1048	goto out;
1049	}
1050	if (unlikely(compound_head(page) != head_page)) {
1051	bad_page(page, "compound_head not consistent", 0);
1052	goto out;
1053	}
1054	ret = 0;
1055	out:
1056	page->mapping = NULL;
1057	clear_compound_head(page);
1058	return ret;
1059	}
1060
1061	static __always_inline bool free_pages_prepare(struct page *page,
1062	unsigned int order, bool check_free)
1063	{
1064	int bad = 0;
1065
1066	VM_BUG_ON_PAGE(PageTail(page), page);
1067
1068	trace_mm_page_free(page, order);
1069	kmemcheck_free_shadow(page, order);
1070
1071	/*
1072	* Check tail pages before head page information is cleared to
1073	* avoid checking PageCompound for order-0 pages.
1074	*/
1075	if (unlikely(order)) {
1076	bool compound = PageCompound(page);
1077	int i;
1078
1079	VM_BUG_ON_PAGE(compound && compound_order(page) != order, page);
1080
1081	if (compound)
1082	ClearPageDoubleMap(page);
1083	for (i = 1; i < (1 << order); i++) {
1084	if (compound)
1085	bad += free_tail_pages_check(page, page + i);
1086	if (unlikely(free_pages_check(page + i))) {
1087	bad++;
1088	continue;
1089	}
1090	(page + i)->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
1091	}
1092	}
1093	if (PageMappingFlags(page))
1094	page->mapping = NULL;
1095	if (memcg_kmem_enabled() && PageKmemcg(page))
1096	memcg_kmem_uncharge(page, order);
1097	if (check_free)
1098	bad += free_pages_check(page);
1099	if (bad)
1100	return false;
1101
1102	page_cpupid_reset_last(page);
1103	page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
1104	reset_page_owner(page, order);
1105
1106	if (!PageHighMem(page)) {
1107	debug_check_no_locks_freed(page_address(page),
1108	PAGE_SIZE << order);
1109	debug_check_no_obj_freed(page_address(page),
1110	PAGE_SIZE << order);
1111	}
1112	arch_free_page(page, order);
1113	kernel_poison_pages(page, 1 << order, 0);
1114	kernel_map_pages(page, 1 << order, 0);
1115	kasan_free_pages(page, order);
1116	#ifdef CONFIG_AMLOGIC_PAGE_TRACE
1117	reset_page_trace(page, order);
1118	#endif /* CONFIG_AMLOGIC_PAGE_TRACE */
1119
1120	return true;
1121	}
1122
1123	#ifdef CONFIG_DEBUG_VM
1124	static inline bool free_pcp_prepare(struct page *page)
1125	{
1126	return free_pages_prepare(page, 0, true);
1127	}
1128
1129	static inline bool bulkfree_pcp_prepare(struct page *page)
1130	{
1131	return false;
1132	}
1133	#else
1134	static bool free_pcp_prepare(struct page *page)
1135	{
1136	return free_pages_prepare(page, 0, false);
1137	}
1138
1139	static bool bulkfree_pcp_prepare(struct page *page)
1140	{
1141	return free_pages_check(page);
1142	}
1143	#endif /* CONFIG_DEBUG_VM */
1144
1145	/*
1146	* Frees a number of pages from the PCP lists
1147	* Assumes all pages on list are in same zone, and of same order.
1148	* count is the number of pages to free.
1149	*
1150	* If the zone was previously in an "all pages pinned" state then look to
1151	* see if this freeing clears that state.
1152	*
1153	* And clear the zone's pages_scanned counter, to hold off the "all pages are
1154	* pinned" detection logic.
1155	*/
1156	static void free_pcppages_bulk(struct zone *zone, int count,
1157	struct per_cpu_pages *pcp)
1158	{
1159	int migratetype = 0;
1160	int batch_free = 0;
1161	unsigned long nr_scanned;
1162	bool isolated_pageblocks;
1163
1164	spin_lock(&zone->lock);
1165	isolated_pageblocks = has_isolate_pageblock(zone);
1166	nr_scanned = node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED);
1167	if (nr_scanned)
1168	__mod_node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED, -nr_scanned);
1169
1170	while (count) {
1171	struct page *page;
1172	struct list_head *list;
1173
1174	/*
1175	* Remove pages from lists in a round-robin fashion. A
1176	* batch_free count is maintained that is incremented when an
1177	* empty list is encountered. This is so more pages are freed
1178	* off fuller lists instead of spinning excessively around empty
1179	* lists
1180	*/
1181	do {
1182	batch_free++;
1183	if (++migratetype == MIGRATE_PCPTYPES)
1184	migratetype = 0;
1185	list = &pcp->lists[migratetype];
1186	} while (list_empty(list));
1187
1188	/* This is the only non-empty list. Free them all. */
1189	if (batch_free == MIGRATE_PCPTYPES)
1190	batch_free = count;
1191
1192	do {
1193	int mt; /* migratetype of the to-be-freed page */
1194
1195	page = list_last_entry(list, struct page, lru);
1196	/* must delete as __free_one_page list manipulates */
1197	list_del(&page->lru);
1198
1199	mt = get_pcppage_migratetype(page);
1200	/* MIGRATE_ISOLATE page should not go to pcplists */
1201	VM_BUG_ON_PAGE(is_migrate_isolate(mt), page);
1202	/* Pageblock could have been isolated meanwhile */
1203	if (unlikely(isolated_pageblocks))
1204	mt = get_pageblock_migratetype(page);
1205
1206	if (bulkfree_pcp_prepare(page))
1207	continue;
1208
1209	__free_one_page(page, page_to_pfn(page), zone, 0, mt);
1210	trace_mm_page_pcpu_drain(page, 0, mt);
1211	} while (--count && --batch_free && !list_empty(list));
1212	}
1213	spin_unlock(&zone->lock);
1214	}
1215
1216	static void free_one_page(struct zone *zone,
1217	struct page *page, unsigned long pfn,
1218	unsigned int order,
1219	int migratetype)
1220	{
1221	unsigned long nr_scanned;
1222	spin_lock(&zone->lock);
1223	nr_scanned = node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED);
1224	if (nr_scanned)
1225	__mod_node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED, -nr_scanned);
1226
1227	if (unlikely(has_isolate_pageblock(zone) ||
1228	is_migrate_isolate(migratetype))) {
1229	migratetype = get_pfnblock_migratetype(page, pfn);
1230	}
1231	__free_one_page(page, pfn, zone, order, migratetype);
1232	spin_unlock(&zone->lock);
1233	}
1234
1235	static void __meminit __init_single_page(struct page *page, unsigned long pfn,
1236	unsigned long zone, int nid)
1237	{
1238	set_page_links(page, zone, nid, pfn);
1239	init_page_count(page);
1240	page_mapcount_reset(page);
1241	page_cpupid_reset_last(page);
1242
1243	INIT_LIST_HEAD(&page->lru);
1244	#ifdef WANT_PAGE_VIRTUAL
1245	/* The shift won't overflow because ZONE_NORMAL is below 4G. */
1246	if (!is_highmem_idx(zone))
1247	set_page_address(page, __va(pfn << PAGE_SHIFT));
1248	#endif
1249	}
1250
1251	static void __meminit __init_single_pfn(unsigned long pfn, unsigned long zone,
1252	int nid)
1253	{
1254	return __init_single_page(pfn_to_page(pfn), pfn, zone, nid);
1255	}
1256
1257	#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
1258	static void init_reserved_page(unsigned long pfn)
1259	{
1260	pg_data_t *pgdat;
1261	int nid, zid;
1262
1263	if (!early_page_uninitialised(pfn))
1264	return;
1265
1266	nid = early_pfn_to_nid(pfn);
1267	pgdat = NODE_DATA(nid);
1268
1269	for (zid = 0; zid < MAX_NR_ZONES; zid++) {
1270	struct zone *zone = &pgdat->node_zones[zid];
1271
1272	if (pfn >= zone->zone_start_pfn && pfn < zone_end_pfn(zone))
1273	break;
1274	}
1275	__init_single_pfn(pfn, zid, nid);
1276	}
1277	#else
1278	static inline void init_reserved_page(unsigned long pfn)
1279	{
1280	}
1281	#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
1282
1283	/*
1284	* Initialised pages do not have PageReserved set. This function is
1285	* called for each range allocated by the bootmem allocator and
1286	* marks the pages PageReserved. The remaining valid pages are later
1287	* sent to the buddy page allocator.
1288	*/
1289	void __meminit reserve_bootmem_region(phys_addr_t start, phys_addr_t end)
1290	{
1291	unsigned long start_pfn = PFN_DOWN(start);
1292	unsigned long end_pfn = PFN_UP(end);
1293
1294	for (; start_pfn < end_pfn; start_pfn++) {
1295	if (pfn_valid(start_pfn)) {
1296	struct page *page = pfn_to_page(start_pfn);
1297
1298	init_reserved_page(start_pfn);
1299
1300	/* Avoid false-positive PageTail() */
1301	INIT_LIST_HEAD(&page->lru);
1302
1303	SetPageReserved(page);
1304	}
1305	}
1306	}
1307
1308	static void __free_pages_ok(struct page *page, unsigned int order)
1309	{
1310	unsigned long flags;
1311	int migratetype;
1312	unsigned long pfn = page_to_pfn(page);
1313
1314	if (!free_pages_prepare(page, order, true))
1315	return;
1316
1317	migratetype = get_pfnblock_migratetype(page, pfn);
1318	local_irq_save(flags);
1319	__count_vm_events(PGFREE, 1 << order);
1320	free_one_page(page_zone(page), page, pfn, order, migratetype);
1321	local_irq_restore(flags);
1322	}
1323
1324	static void __init __free_pages_boot_core(struct page *page, unsigned int order)
1325	{
1326	unsigned int nr_pages = 1 << order;
1327	struct page *p = page;
1328	unsigned int loop;
1329
1330	prefetchw(p);
1331	for (loop = 0; loop < (nr_pages - 1); loop++, p++) {
1332	prefetchw(p + 1);
1333	__ClearPageReserved(p);
1334	set_page_count(p, 0);
1335	}
1336	__ClearPageReserved(p);
1337	set_page_count(p, 0);
1338
1339	page_zone(page)->managed_pages += nr_pages;
1340	set_page_refcounted(page);
1341	__free_pages(page, order);
1342	}
1343
1344	#if defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) || \
1345	defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP)
1346
1347	static struct mminit_pfnnid_cache early_pfnnid_cache __meminitdata;
1348
1349	int __meminit early_pfn_to_nid(unsigned long pfn)
1350	{
1351	static DEFINE_SPINLOCK(early_pfn_lock);
1352	int nid;
1353
1354	spin_lock(&early_pfn_lock);
1355	nid = __early_pfn_to_nid(pfn, &early_pfnnid_cache);
1356	if (nid < 0)
1357	nid = first_online_node;
1358	spin_unlock(&early_pfn_lock);
1359
1360	return nid;
1361	}
1362	#endif
1363
1364	#ifdef CONFIG_NODES_SPAN_OTHER_NODES
1365	static inline bool __meminit meminit_pfn_in_nid(unsigned long pfn, int node,
1366	struct mminit_pfnnid_cache *state)
1367	{
1368	int nid;
1369
1370	nid = __early_pfn_to_nid(pfn, state);
1371	if (nid >= 0 && nid != node)
1372	return false;
1373	return true;
1374	}
1375
1376	/* Only safe to use early in boot when initialisation is single-threaded */
1377	static inline bool __meminit early_pfn_in_nid(unsigned long pfn, int node)
1378	{
1379	return meminit_pfn_in_nid(pfn, node, &early_pfnnid_cache);
1380	}
1381
1382	#else
1383
1384	static inline bool __meminit early_pfn_in_nid(unsigned long pfn, int node)
1385	{
1386	return true;
1387	}
1388	static inline bool __meminit meminit_pfn_in_nid(unsigned long pfn, int node,
1389	struct mminit_pfnnid_cache *state)
1390	{
1391	return true;
1392	}
1393	#endif
1394
1395
1396	void __init __free_pages_bootmem(struct page *page, unsigned long pfn,
1397	unsigned int order)
1398	{
1399	if (early_page_uninitialised(pfn))
1400	return;
1401	return __free_pages_boot_core(page, order);
1402	}
1403
1404	/*
1405	* Check that the whole (or subset of) a pageblock given by the interval of
1406	* [start_pfn, end_pfn) is valid and within the same zone, before scanning it
1407	* with the migration of free compaction scanner. The scanners then need to
1408	* use only pfn_valid_within() check for arches that allow holes within
1409	* pageblocks.
1410	*
1411	* Return struct page pointer of start_pfn, or NULL if checks were not passed.
1412	*
1413	* It's possible on some configurations to have a setup like node0 node1 node0
1414	* i.e. it's possible that all pages within a zones range of pages do not
1415	* belong to a single zone. We assume that a border between node0 and node1
1416	* can occur within a single pageblock, but not a node0 node1 node0
1417	* interleaving within a single pageblock. It is therefore sufficient to check
1418	* the first and last page of a pageblock and avoid checking each individual
1419	* page in a pageblock.
1420	*/
1421	struct page *__pageblock_pfn_to_page(unsigned long start_pfn,
1422	unsigned long end_pfn, struct zone *zone)
1423	{
1424	struct page *start_page;
1425	struct page *end_page;
1426
1427	/* end_pfn is one past the range we are checking */
1428	end_pfn--;
1429
1430	if (!pfn_valid(start_pfn) || !pfn_valid(end_pfn))
1431	return NULL;
1432
1433	start_page = pfn_to_page(start_pfn);
1434
1435	if (page_zone(start_page) != zone)
1436	return NULL;
1437
1438	end_page = pfn_to_page(end_pfn);
1439
1440	/* This gives a shorter code than deriving page_zone(end_page) */
1441	if (page_zone_id(start_page) != page_zone_id(end_page))
1442	return NULL;
1443
1444	return start_page;
1445	}
1446
1447	void set_zone_contiguous(struct zone *zone)
1448	{
1449	unsigned long block_start_pfn = zone->zone_start_pfn;
1450	unsigned long block_end_pfn;
1451
1452	block_end_pfn = ALIGN(block_start_pfn + 1, pageblock_nr_pages);
1453	for (; block_start_pfn < zone_end_pfn(zone);
1454	block_start_pfn = block_end_pfn,
1455	block_end_pfn += pageblock_nr_pages) {
1456
1457	block_end_pfn = min(block_end_pfn, zone_end_pfn(zone));
1458
1459	if (!__pageblock_pfn_to_page(block_start_pfn,
1460	block_end_pfn, zone))
1461	return;
1462	}
1463
1464	/* We confirm that there is no hole */
1465	zone->contiguous = true;
1466	}
1467
1468	void clear_zone_contiguous(struct zone *zone)
1469	{
1470	zone->contiguous = false;
1471	}
1472
1473	#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
1474	static void __init deferred_free_range(struct page *page,
1475	unsigned long pfn, int nr_pages)
1476	{
1477	int i;
1478
1479	if (!page)
1480	return;
1481
1482	/* Free a large naturally-aligned chunk if possible */
1483	if (nr_pages == pageblock_nr_pages &&
1484	(pfn & (pageblock_nr_pages - 1)) == 0) {
1485	set_pageblock_migratetype(page, MIGRATE_MOVABLE);
1486	__free_pages_boot_core(page, pageblock_order);
1487	return;
1488	}
1489
1490	for (i = 0; i < nr_pages; i++, page++, pfn++) {
1491	if ((pfn & (pageblock_nr_pages - 1)) == 0)
1492	set_pageblock_migratetype(page, MIGRATE_MOVABLE);
1493	__free_pages_boot_core(page, 0);
1494	}
1495	}
1496
1497	/* Completion tracking for deferred_init_memmap() threads */
1498	static atomic_t pgdat_init_n_undone __initdata;
1499	static __initdata DECLARE_COMPLETION(pgdat_init_all_done_comp);
1500
1501	static inline void __init pgdat_init_report_one_done(void)
1502	{
1503	if (atomic_dec_and_test(&pgdat_init_n_undone))
1504	complete(&pgdat_init_all_done_comp);
1505	}
1506
1507	/* Initialise remaining memory on a node */
1508	static int __init deferred_init_memmap(void *data)
1509	{
1510	pg_data_t *pgdat = data;
1511	int nid = pgdat->node_id;
1512	struct mminit_pfnnid_cache nid_init_state = { };
1513	unsigned long start = jiffies;
1514	unsigned long nr_pages = 0;
1515	unsigned long walk_start, walk_end;
1516	int i, zid;
1517	struct zone *zone;
1518	unsigned long first_init_pfn = pgdat->first_deferred_pfn;
1519	const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id);
1520
1521	if (first_init_pfn == ULONG_MAX) {
1522	pgdat_init_report_one_done();
1523	return 0;
1524	}
1525
1526	/* Bind memory initialisation thread to a local node if possible */
1527	if (!cpumask_empty(cpumask))
1528	set_cpus_allowed_ptr(current, cpumask);
1529
1530	/* Sanity check boundaries */
1531	BUG_ON(pgdat->first_deferred_pfn < pgdat->node_start_pfn);
1532	BUG_ON(pgdat->first_deferred_pfn > pgdat_end_pfn(pgdat));
1533	pgdat->first_deferred_pfn = ULONG_MAX;
1534
1535	/* Only the highest zone is deferred so find it */
1536	for (zid = 0; zid < MAX_NR_ZONES; zid++) {
1537	zone = pgdat->node_zones + zid;
1538	if (first_init_pfn < zone_end_pfn(zone))
1539	break;
1540	}
1541
1542	for_each_mem_pfn_range(i, nid, &walk_start, &walk_end, NULL) {
1543	unsigned long pfn, end_pfn;
1544	struct page *page = NULL;
1545	struct page *free_base_page = NULL;
1546	unsigned long free_base_pfn = 0;
1547	int nr_to_free = 0;
1548
1549	end_pfn = min(walk_end, zone_end_pfn(zone));
1550	pfn = first_init_pfn;
1551	if (pfn < walk_start)
1552	pfn = walk_start;
1553	if (pfn < zone->zone_start_pfn)
1554	pfn = zone->zone_start_pfn;
1555
1556	for (; pfn < end_pfn; pfn++) {
1557	if (!pfn_valid_within(pfn))
1558	goto free_range;
1559
1560	/*
1561	* Ensure pfn_valid is checked every
1562	* pageblock_nr_pages for memory holes
1563	*/
1564	if ((pfn & (pageblock_nr_pages - 1)) == 0) {
1565	if (!pfn_valid(pfn)) {
1566	page = NULL;
1567	goto free_range;
1568	}
1569	}
1570
1571	if (!meminit_pfn_in_nid(pfn, nid, &nid_init_state)) {
1572	page = NULL;
1573	goto free_range;
1574	}
1575
1576	/* Minimise pfn page lookups and scheduler checks */
1577	if (page && (pfn & (pageblock_nr_pages - 1)) != 0) {
1578	page++;
1579	} else {
1580	nr_pages += nr_to_free;
1581	deferred_free_range(free_base_page,
1582	free_base_pfn, nr_to_free);
1583	free_base_page = NULL;
1584	free_base_pfn = nr_to_free = 0;
1585
1586	page = pfn_to_page(pfn);
1587	cond_resched();
1588	}
1589
1590	if (page->flags) {
1591	VM_BUG_ON(page_zone(page) != zone);
1592	goto free_range;
1593	}
1594
1595	__init_single_page(page, pfn, zid, nid);
1596	if (!free_base_page) {
1597	free_base_page = page;
1598	free_base_pfn = pfn;
1599	nr_to_free = 0;
1600	}
1601	nr_to_free++;
1602
1603	/* Where possible, batch up pages for a single free */
1604	continue;
1605	free_range:
1606	/* Free the current block of pages to allocator */
1607	nr_pages += nr_to_free;
1608	deferred_free_range(free_base_page, free_base_pfn,
1609	nr_to_free);
1610	free_base_page = NULL;
1611	free_base_pfn = nr_to_free = 0;
1612	}
1613	/* Free the last block of pages to allocator */
1614	nr_pages += nr_to_free;
1615	deferred_free_range(free_base_page, free_base_pfn, nr_to_free);
1616
1617	first_init_pfn = max(end_pfn, first_init_pfn);
1618	}
1619
1620	/* Sanity check that the next zone really is unpopulated */
1621	WARN_ON(++zid < MAX_NR_ZONES && populated_zone(++zone));
1622
1623	pr_info("node %d initialised, %lu pages in %ums\n", nid, nr_pages,
1624	jiffies_to_msecs(jiffies - start));
1625
1626	pgdat_init_report_one_done();
1627	return 0;
1628	}
1629	#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
1630
1631	void __init page_alloc_init_late(void)
1632	{
1633	struct zone *zone;
1634
1635	#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
1636	int nid;
1637
1638	/* There will be num_node_state(N_MEMORY) threads */
1639	atomic_set(&pgdat_init_n_undone, num_node_state(N_MEMORY));
1640	for_each_node_state(nid, N_MEMORY) {
1641	kthread_run(deferred_init_memmap, NODE_DATA(nid), "pgdatinit%d", nid);
1642	}
1643
1644	/* Block until all are initialised */
1645	wait_for_completion(&pgdat_init_all_done_comp);
1646
1647	/* Reinit limits that are based on free pages after the kernel is up */
1648	files_maxfiles_init();
1649	#endif
1650	#ifdef CONFIG_ARCH_DISCARD_MEMBLOCK
1651	/* Discard memblock private memory */
1652	memblock_discard();
1653	#endif
1654
1655	for_each_populated_zone(zone)
1656	set_zone_contiguous(zone);
1657	}
1658
1659	#ifdef CONFIG_CMA
1660	/* Free whole pageblock and set its migration type to MIGRATE_CMA. */
1661	void __init init_cma_reserved_pageblock(struct page *page)
1662	{
1663	unsigned i = pageblock_nr_pages;
1664	struct page *p = page;
1665
1666	do {
1667	__ClearPageReserved(p);
1668	set_page_count(p, 0);
1669	} while (++p, --i);
1670
1671	set_pageblock_migratetype(page, MIGRATE_CMA);
1672
1673	if (pageblock_order >= MAX_ORDER) {
1674	i = pageblock_nr_pages;
1675	p = page;
1676	do {
1677	set_page_refcounted(p);
1678	__free_pages(p, MAX_ORDER - 1);
1679	p += MAX_ORDER_NR_PAGES;
1680	} while (i -= MAX_ORDER_NR_PAGES);
1681	} else {
1682	set_page_refcounted(page);
1683	__free_pages(page, pageblock_order);
1684	}
1685
1686	adjust_managed_page_count(page, pageblock_nr_pages);
1687	}
1688	#endif
1689
1690	/*
1691	* The order of subdivision here is critical for the IO subsystem.
1692	* Please do not alter this order without good reasons and regression
1693	* testing. Specifically, as large blocks of memory are subdivided,
1694	* the order in which smaller blocks are delivered depends on the order
1695	* they're subdivided in this function. This is the primary factor
1696	* influencing the order in which pages are delivered to the IO
1697	* subsystem according to empirical testing, and this is also justified
1698	* by considering the behavior of a buddy system containing a single
1699	* large block of memory acted on by a series of small allocations.
1700	* This behavior is a critical factor in sglist merging's success.
1701	*
1702	* -- nyc
1703	*/
1704	static inline void expand(struct zone *zone, struct page *page,
1705	int low, int high, struct free_area *area,
1706	int migratetype)
1707	{
1708	unsigned long size = 1 << high;
1709
1710	while (high > low) {
1711	area--;
1712	high--;
1713	size >>= 1;
1714	VM_BUG_ON_PAGE(bad_range(zone, &page[size]), &page[size]);
1715
1716	/*
1717	* Mark as guard pages (or page), that will allow to
1718	* merge back to allocator when buddy will be freed.
1719	* Corresponding page table entries will not be touched,
1720	* pages will stay not present in virtual address space
1721	*/
1722	if (set_page_guard(zone, &page[size], high, migratetype))
1723	continue;
1724
1725	list_add(&page[size].lru, &area->free_list[migratetype]);
1726	area->nr_free++;
1727	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
1728	set_pcppage_migratetype(&page[size], migratetype);
1729	__mod_zone_migrate_state(zone, (1 << high), migratetype);
1730	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
1731	set_page_order(&page[size], high);
1732	}
1733	}
1734
1735	static void check_new_page_bad(struct page *page)
1736	{
1737	const char *bad_reason = NULL;
1738	unsigned long bad_flags = 0;
1739
1740	if (unlikely(atomic_read(&page->_mapcount) != -1))
1741	bad_reason = "nonzero mapcount";
1742	if (unlikely(page->mapping != NULL))
1743	bad_reason = "non-NULL mapping";
1744	if (unlikely(page_ref_count(page) != 0))
1745	bad_reason = "nonzero _count";
1746	if (unlikely(page->flags & __PG_HWPOISON)) {
1747	bad_reason = "HWPoisoned (hardware-corrupted)";
1748	bad_flags = __PG_HWPOISON;
1749	/* Don't complain about hwpoisoned pages */
1750	page_mapcount_reset(page); /* remove PageBuddy */
1751	return;
1752	}
1753	if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_PREP)) {
1754	bad_reason = "PAGE_FLAGS_CHECK_AT_PREP flag set";
1755	bad_flags = PAGE_FLAGS_CHECK_AT_PREP;
1756	}
1757	#ifdef CONFIG_MEMCG
1758	if (unlikely(page->mem_cgroup))
1759	bad_reason = "page still charged to cgroup";
1760	#endif
1761	bad_page(page, bad_reason, bad_flags);
1762	}
1763
1764	/*
1765	* This page is about to be returned from the page allocator
1766	*/
1767	static inline int check_new_page(struct page *page)
1768	{
1769	if (likely(page_expected_state(page,
1770	PAGE_FLAGS_CHECK_AT_PREP|__PG_HWPOISON)))
1771	return 0;
1772
1773	check_new_page_bad(page);
1774	return 1;
1775	}
1776
1777	static inline bool free_pages_prezeroed(bool poisoned)
1778	{
1779	return IS_ENABLED(CONFIG_PAGE_POISONING_ZERO) &&
1780	page_poisoning_enabled() && poisoned;
1781	}
1782
1783	#ifdef CONFIG_DEBUG_VM
1784	static bool check_pcp_refill(struct page *page)
1785	{
1786	return false;
1787	}
1788
1789	static bool check_new_pcp(struct page *page)
1790	{
1791	return check_new_page(page);
1792	}
1793	#else
1794	static bool check_pcp_refill(struct page *page)
1795	{
1796	return check_new_page(page);
1797	}
1798	static bool check_new_pcp(struct page *page)
1799	{
1800	return false;
1801	}
1802	#endif /* CONFIG_DEBUG_VM */
1803
1804	static bool check_new_pages(struct page *page, unsigned int order)
1805	{
1806	int i;
1807	for (i = 0; i < (1 << order); i++) {
1808	struct page *p = page + i;
1809
1810	if (unlikely(check_new_page(p)))
1811	return true;
1812	}
1813
1814	return false;
1815	}
1816
1817	inline void post_alloc_hook(struct page *page, unsigned int order,
1818	gfp_t gfp_flags)
1819	{
1820	set_page_private(page, 0);
1821	set_page_refcounted(page);
1822
1823	arch_alloc_page(page, order);
1824	kernel_map_pages(page, 1 << order, 1);
1825	kernel_poison_pages(page, 1 << order, 1);
1826	kasan_alloc_pages(page, order);
1827	set_page_owner(page, order, gfp_flags);
1828	}
1829
1830	static void prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags,
1831	unsigned int alloc_flags)
1832	{
1833	int i;
1834	bool poisoned = true;
1835
1836	for (i = 0; i < (1 << order); i++) {
1837	struct page *p = page + i;
1838	if (poisoned)
1839	poisoned &= page_is_poisoned(p);
1840	}
1841
1842	post_alloc_hook(page, order, gfp_flags);
1843
1844	if (!free_pages_prezeroed(poisoned) && (gfp_flags & __GFP_ZERO))
1845	for (i = 0; i < (1 << order); i++)
1846	clear_highpage(page + i);
1847
1848	if (order && (gfp_flags & __GFP_COMP))
1849	prep_compound_page(page, order);
1850
1851	/*
1852	* page is set pfmemalloc when ALLOC_NO_WATERMARKS was necessary to
1853	* allocate the page. The expectation is that the caller is taking
1854	* steps that will free more memory. The caller should avoid the page
1855	* being used for !PFMEMALLOC purposes.
1856	*/
1857	if (alloc_flags & ALLOC_NO_WATERMARKS)
1858	set_page_pfmemalloc(page);
1859	else
1860	clear_page_pfmemalloc(page);
1861	}
1862
1863	/*
1864	* Go through the free lists for the given migratetype and remove
1865	* the smallest available page from the freelists
1866	*/
1867	static inline
1868	struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
1869	int migratetype)
1870	{
1871	unsigned int current_order;
1872	struct free_area *area;
1873	struct page *page;
1874
1875	/* Find a page of the appropriate size in the preferred list */
1876	for (current_order = order; current_order < MAX_ORDER; ++current_order) {
1877	area = &(zone->free_area[current_order]);
1878	page = list_first_entry_or_null(&area->free_list[migratetype],
1879	struct page, lru);
1880	if (!page)
1881	continue;
1882	list_del(&page->lru);
1883	rmv_page_order(page);
1884	area->nr_free--;
1885	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
1886	__mod_zone_migrate_state(zone, -(1 << current_order),
1887	migratetype);
1888	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
1889	expand(zone, page, order, current_order, area, migratetype);
1890	set_pcppage_migratetype(page, migratetype);
1891	return page;
1892	}
1893
1894	return NULL;
1895	}
1896
1897
1898	/*
1899	* This array describes the order lists are fallen back to when
1900	* the free lists for the desirable migrate type are depleted
1901	*/
1902	static int fallbacks[MIGRATE_TYPES][4] = {
1903	[MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_TYPES },
1904	[MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_TYPES },
1905	[MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_TYPES },
1906	#ifdef CONFIG_CMA
1907	[MIGRATE_CMA] = { MIGRATE_TYPES }, /* Never used */
1908	#endif
1909	#ifdef CONFIG_MEMORY_ISOLATION
1910	[MIGRATE_ISOLATE] = { MIGRATE_TYPES }, /* Never used */
1911	#endif
1912	};
1913
1914	#ifdef CONFIG_CMA
1915	static struct page *__rmqueue_cma_fallback(struct zone *zone,
1916	unsigned int order)
1917	{
1918	return __rmqueue_smallest(zone, order, MIGRATE_CMA);
1919	}
1920	#else
1921	static inline struct page *__rmqueue_cma_fallback(struct zone *zone,
1922	unsigned int order) { return NULL; }
1923	#endif
1924
1925	/*
1926	* Move the free pages in a range to the free lists of the requested type.
1927	* Note that start_page and end_pages are not aligned on a pageblock
1928	* boundary. If alignment is required, use move_freepages_block()
1929	*/
1930	int move_freepages(struct zone *zone,
1931	struct page *start_page, struct page *end_page,
1932	int migratetype)
1933	{
1934	struct page *page;
1935	unsigned int order;
1936	int pages_moved = 0;
1937	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
1938	int list_type;
1939	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
1940
1941	#ifndef CONFIG_HOLES_IN_ZONE
1942	/*
1943	* page_zone is not safe to call in this context when
1944	* CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
1945	* anyway as we check zone boundaries in move_freepages_block().
1946	* Remove at a later date when no bug reports exist related to
1947	* grouping pages by mobility
1948	*/
1949	VM_BUG_ON(page_zone(start_page) != page_zone(end_page));
1950	#endif
1951
1952	for (page = start_page; page <= end_page;) {
1953	if (!pfn_valid_within(page_to_pfn(page))) {
1954	page++;
1955	continue;
1956	}
1957
1958	/* Make sure we are not inadvertently changing nodes */
1959	VM_BUG_ON_PAGE(page_to_nid(page) != zone_to_nid(zone), page);
1960
1961	if (!PageBuddy(page)) {
1962	page++;
1963	continue;
1964	}
1965
1966	order = page_order(page);
1967	list_move(&page->lru,
1968	&zone->free_area[order].free_list[migratetype]);
1969	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
1970	list_type = get_pcppage_migratetype(page);
1971	__mod_zone_migrate_state(zone, -(1 << order), list_type);
1972	__mod_zone_migrate_state(zone, (1 << order), migratetype);
1973	set_pcppage_migratetype(page, migratetype);
1974	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
1975	page += 1 << order;
1976	pages_moved += 1 << order;
1977	}
1978
1979	return pages_moved;
1980	}
1981
1982	int move_freepages_block(struct zone *zone, struct page *page,
1983	int migratetype)
1984	{
1985	unsigned long start_pfn, end_pfn;
1986	struct page *start_page, *end_page;
1987
1988	start_pfn = page_to_pfn(page);
1989	start_pfn = start_pfn & ~(pageblock_nr_pages-1);
1990	start_page = pfn_to_page(start_pfn);
1991	end_page = start_page + pageblock_nr_pages - 1;
1992	end_pfn = start_pfn + pageblock_nr_pages - 1;
1993
1994	/* Do not cross zone boundaries */
1995	if (!zone_spans_pfn(zone, start_pfn))
1996	start_page = page;
1997	if (!zone_spans_pfn(zone, end_pfn))
1998	return 0;
1999
2000	return move_freepages(zone, start_page, end_page, migratetype);
2001	}
2002
2003	static void change_pageblock_range(struct page *pageblock_page,
2004	int start_order, int migratetype)
2005	{
2006	int nr_pageblocks = 1 << (start_order - pageblock_order);
2007
2008	while (nr_pageblocks--) {
2009	set_pageblock_migratetype(pageblock_page, migratetype);
2010	pageblock_page += pageblock_nr_pages;
2011	}
2012	}
2013
2014	/*
2015	* When we are falling back to another migratetype during allocation, try to
2016	* steal extra free pages from the same pageblocks to satisfy further
2017	* allocations, instead of polluting multiple pageblocks.
2018	*
2019	* If we are stealing a relatively large buddy page, it is likely there will
2020	* be more free pages in the pageblock, so try to steal them all. For
2021	* reclaimable and unmovable allocations, we steal regardless of page size,
2022	* as fragmentation caused by those allocations polluting movable pageblocks
2023	* is worse than movable allocations stealing from unmovable and reclaimable
2024	* pageblocks.
2025	*/
2026	static bool can_steal_fallback(unsigned int order, int start_mt)
2027	{
2028	/*
2029	* Leaving this order check is intended, although there is
2030	* relaxed order check in next check. The reason is that
2031	* we can actually steal whole pageblock if this condition met,
2032	* but, below check doesn't guarantee it and that is just heuristic
2033	* so could be changed anytime.
2034	*/
2035	if (order >= pageblock_order)
2036	return true;
2037
2038	if (order >= pageblock_order / 2 ||
2039	start_mt == MIGRATE_RECLAIMABLE ||
2040	start_mt == MIGRATE_UNMOVABLE ||
2041	page_group_by_mobility_disabled)
2042	return true;
2043
2044	return false;
2045	}
2046
2047	/*
2048	* This function implements actual steal behaviour. If order is large enough,
2049	* we can steal whole pageblock. If not, we first move freepages in this
2050	* pageblock and check whether half of pages are moved or not. If half of
2051	* pages are moved, we can change migratetype of pageblock and permanently
2052	* use it's pages as requested migratetype in the future.
2053	*/
2054	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
2055	static void steal_suitable_fallback(struct zone *zone, struct page *page,
2056	int start_type, int *list_type)
2057	#else
2058	static void steal_suitable_fallback(struct zone *zone, struct page *page,
2059	int start_type)
2060	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
2061	{
2062	unsigned int current_order = page_order(page);
2063	int pages;
2064
2065	/* Take ownership for orders >= pageblock_order */
2066	if (current_order >= pageblock_order) {
2067	change_pageblock_range(page, current_order, start_type);
2068	return;
2069	}
2070
2071	pages = move_freepages_block(zone, page, start_type);
2072	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
2073	*list_type = start_type;
2074	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
2075
2076	/* Claim the whole block if over half of it is free */
2077	if (pages >= (1 << (pageblock_order-1)) ||
2078	page_group_by_mobility_disabled)
2079	set_pageblock_migratetype(page, start_type);
2080	}
2081
2082	/*
2083	* Check whether there is a suitable fallback freepage with requested order.
2084	* If only_stealable is true, this function returns fallback_mt only if
2085	* we can steal other freepages all together. This would help to reduce
2086	* fragmentation due to mixed migratetype pages in one pageblock.
2087	*/
2088	int find_suitable_fallback(struct free_area *area, unsigned int order,
2089	int migratetype, bool only_stealable, bool *can_steal)
2090	{
2091	int i;
2092	int fallback_mt;
2093
2094	if (area->nr_free == 0)
2095	return -1;
2096
2097	*can_steal = false;
2098	for (i = 0;; i++) {
2099	fallback_mt = fallbacks[migratetype][i];
2100	if (fallback_mt == MIGRATE_TYPES)
2101	break;
2102
2103	if (list_empty(&area->free_list[fallback_mt]))
2104	continue;
2105
2106	if (can_steal_fallback(order, migratetype))
2107	*can_steal = true;
2108
2109	if (!only_stealable)
2110	return fallback_mt;
2111
2112	if (*can_steal)
2113	return fallback_mt;
2114	}
2115
2116	return -1;
2117	}
2118
2119	/*
2120	* Reserve a pageblock for exclusive use of high-order atomic allocations if
2121	* there are no empty page blocks that contain a page with a suitable order
2122	*/
2123	static void reserve_highatomic_pageblock(struct page *page, struct zone *zone,
2124	unsigned int alloc_order)
2125	{
2126	int mt;
2127	unsigned long max_managed, flags;
2128
2129	/*
2130	* Limit the number reserved to 1 pageblock or roughly 1% of a zone.
2131	* Check is race-prone but harmless.
2132	*/
2133	max_managed = (zone->managed_pages / 100) + pageblock_nr_pages;
2134	if (zone->nr_reserved_highatomic >= max_managed)
2135	return;
2136
2137	spin_lock_irqsave(&zone->lock, flags);
2138
2139	/* Recheck the nr_reserved_highatomic limit under the lock */
2140	if (zone->nr_reserved_highatomic >= max_managed)
2141	goto out_unlock;
2142
2143	/* Yoink! */
2144	mt = get_pageblock_migratetype(page);
2145	if (mt != MIGRATE_HIGHATOMIC &&
2146	!is_migrate_isolate(mt) && !is_migrate_cma(mt)) {
2147	zone->nr_reserved_highatomic += pageblock_nr_pages;
2148	set_pageblock_migratetype(page, MIGRATE_HIGHATOMIC);
2149	move_freepages_block(zone, page, MIGRATE_HIGHATOMIC);
2150	}
2151
2152	out_unlock:
2153	spin_unlock_irqrestore(&zone->lock, flags);
2154	}
2155
2156	/*
2157	* Used when an allocation is about to fail under memory pressure. This
2158	* potentially hurts the reliability of high-order allocations when under
2159	* intense memory pressure but failed atomic allocations should be easier
2160	* to recover from than an OOM.
2161	*/
2162	static void unreserve_highatomic_pageblock(const struct alloc_context *ac)
2163	{
2164	struct zonelist *zonelist = ac->zonelist;
2165	unsigned long flags;
2166	struct zoneref *z;
2167	struct zone *zone;
2168	struct page *page;
2169	int order;
2170
2171	for_each_zone_zonelist_nodemask(zone, z, zonelist, ac->high_zoneidx,
2172	ac->nodemask) {
2173	/* Preserve at least one pageblock */
2174	if (zone->nr_reserved_highatomic <= pageblock_nr_pages)
2175	continue;
2176
2177	spin_lock_irqsave(&zone->lock, flags);
2178	for (order = 0; order < MAX_ORDER; order++) {
2179	struct free_area *area = &(zone->free_area[order]);
2180
2181	page = list_first_entry_or_null(
2182	&area->free_list[MIGRATE_HIGHATOMIC],
2183	struct page, lru);
2184	if (!page)
2185	continue;
2186
2187	/*
2188	* In page freeing path, migratetype change is racy so
2189	* we can counter several free pages in a pageblock
2190	* in this loop althoug we changed the pageblock type
2191	* from highatomic to ac->migratetype. So we should
2192	* adjust the count once.
2193	*/
2194	if (get_pageblock_migratetype(page) ==
2195	MIGRATE_HIGHATOMIC) {
2196	/*
2197	* It should never happen but changes to
2198	* locking could inadvertently allow a per-cpu
2199	* drain to add pages to MIGRATE_HIGHATOMIC
2200	* while unreserving so be safe and watch for
2201	* underflows.
2202	*/
2203	zone->nr_reserved_highatomic -= min(
2204	pageblock_nr_pages,
2205	zone->nr_reserved_highatomic);
2206	}
2207
2208	/*
2209	* Convert to ac->migratetype and avoid the normal
2210	* pageblock stealing heuristics. Minimally, the caller
2211	* is doing the work and needs the pages. More
2212	* importantly, if the block was always converted to
2213	* MIGRATE_UNMOVABLE or another type then the number
2214	* of pageblocks that cannot be completely freed
2215	* may increase.
2216	*/
2217	set_pageblock_migratetype(page, ac->migratetype);
2218	move_freepages_block(zone, page, ac->migratetype);
2219	spin_unlock_irqrestore(&zone->lock, flags);
2220	return;
2221	}
2222	spin_unlock_irqrestore(&zone->lock, flags);
2223	}
2224	}
2225
2226	/* Remove an element from the buddy allocator from the fallback list */
2227	static inline struct page *
2228	__rmqueue_fallback(struct zone *zone, unsigned int order, int start_migratetype)
2229	{
2230	struct free_area *area;
2231	unsigned int current_order;
2232	struct page *page;
2233	int fallback_mt;
2234	bool can_steal;
2235	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
2236	int list_type;
2237	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
2238
2239	/* Find the largest possible block of pages in the other list */
2240	for (current_order = MAX_ORDER-1;
2241	current_order >= order && current_order <= MAX_ORDER-1;
2242	--current_order) {
2243	area = &(zone->free_area[current_order]);
2244	fallback_mt = find_suitable_fallback(area, current_order,
2245	start_migratetype, false, &can_steal);
2246	if (fallback_mt == -1)
2247	continue;
2248
2249	page = list_first_entry(&area->free_list[fallback_mt],
2250	struct page, lru);
2251	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
2252	/* list_type may change after try_to_steal_freepages */
2253	list_type = fallback_mt;
2254	if (can_steal)
2255	steal_suitable_fallback(zone, page, start_migratetype,
2256	&list_type);
2257	#else
2258	if (can_steal)
2259	steal_suitable_fallback(zone, page, start_migratetype);
2260	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
2261
2262	/* Remove the page from the freelists */
2263	area->nr_free--;
2264	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
2265	__mod_zone_migrate_state(zone, -(1 << current_order),
2266	list_type);
2267	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
2268	list_del(&page->lru);
2269	rmv_page_order(page);
2270
2271	expand(zone, page, order, current_order, area,
2272	start_migratetype);
2273	/*
2274	* The pcppage_migratetype may differ from pageblock's
2275	* migratetype depending on the decisions in
2276	* find_suitable_fallback(). This is OK as long as it does not
2277	* differ for MIGRATE_CMA pageblocks. Those can be used as
2278	* fallback only via special __rmqueue_cma_fallback() function
2279	*/
2280	set_pcppage_migratetype(page, start_migratetype);
2281
2282	trace_mm_page_alloc_extfrag(page, order, current_order,
2283	start_migratetype, fallback_mt);
2284
2285	return page;
2286	}
2287
2288	return NULL;
2289	}
2290
2291	/*
2292	* Do the hard work of removing an element from the buddy allocator.
2293	* Call me with the zone->lock already held.
2294	*/
2295	#ifdef CONFIG_AMLOGIC_CMA
2296	static struct page *__rmqueue(struct zone *zone, unsigned int order,
2297	int migratetype, bool cma)
2298	#else
2299	static struct page *__rmqueue(struct zone *zone, unsigned int order,
2300	int migratetype)
2301	#endif /* CONFIG_AMLOGIC_CMA */
2302	{
2303	struct page *page;
2304
2305	#ifdef CONFIG_AMLOGIC_CMA
2306	/* use CMA first */
2307	if (migratetype == MIGRATE_MOVABLE && cma) {
2308	page = __rmqueue_cma_fallback(zone, order);
2309	if (page) {
2310	trace_mm_page_alloc_zone_locked(page, order,
2311	MIGRATE_CMA);
2312	return page;
2313	}
2314	}
2315	#endif /* CONFIG_AMLOGIC_CMA */
2316
2317	page = __rmqueue_smallest(zone, order, migratetype);
2318	if (unlikely(!page)) {
2319	#ifndef CONFIG_AMLOGIC_CMA /* no need to try again */
2320	if (migratetype == MIGRATE_MOVABLE)
2321	page = __rmqueue_cma_fallback(zone, order);
2322	#endif /* !CONFIG_AMLOGIC_CMA */
2323
2324	if (!page)
2325	page = __rmqueue_fallback(zone, order, migratetype);
2326	}
2327
2328	trace_mm_page_alloc_zone_locked(page, order, migratetype);
2329	return page;
2330	}
2331
2332	#ifdef CONFIG_AMLOGIC_CMA
2333	/*
2334	* get page but not cma
2335	*/
2336	static struct page *rmqueue_no_cma(struct zone *zone, unsigned int order,
2337	int migratetype)
2338	{
2339	struct page *page;
2340
2341	spin_lock(&zone->lock);
2342	page = __rmqueue_smallest(zone, order, migratetype);
2343	if (unlikely(!page))
2344	if (!page)
2345	page = __rmqueue_fallback(zone, order, migratetype);
2346	WARN_ON(page && is_migrate_cma(get_pcppage_migratetype(page)));
2347	__mod_zone_page_state(zone, NR_FREE_PAGES, -(1 << order));
2348	spin_unlock(&zone->lock);
2349	return page;
2350	}
2351	#endif /* CONFIG_AMLOGIC_CMA */
2352
2353	/*
2354	* Obtain a specified number of elements from the buddy allocator, all under
2355	* a single hold of the lock, for efficiency. Add them to the supplied list.
2356	* Returns the number of new pages which were placed at *list.
2357	*/
2358	#ifdef CONFIG_AMLOGIC_CMA
2359	static int rmqueue_bulk(struct zone *zone, unsigned int order,
2360	unsigned long count, struct list_head *list,
2361	int migratetype, bool cold, bool cma)
2362	#else
2363	static int rmqueue_bulk(struct zone *zone, unsigned int order,
2364	unsigned long count, struct list_head *list,
2365	int migratetype, bool cold)
2366	#endif /* CONFIG_AMLOGIC_CMA */
2367	{
2368	int i, alloced = 0;
2369
2370	spin_lock(&zone->lock);
2371	for (i = 0; i < count; ++i) {
2372	#ifdef CONFIG_AMLOGIC_CMA
2373	struct page *page = __rmqueue(zone, order, migratetype, cma);
2374	#else
2375	struct page *page = __rmqueue(zone, order, migratetype);
2376	#endif /* CONFIG_AMLOGIC_CMA */
2377	if (unlikely(page == NULL))
2378	break;
2379
2380	if (unlikely(check_pcp_refill(page)))
2381	continue;
2382
2383	/*
2384	* Split buddy pages returned by expand() are received here
2385	* in physical page order. The page is added to the callers and
2386	* list and the list head then moves forward. From the callers
2387	* perspective, the linked list is ordered by page number in
2388	* some conditions. This is useful for IO devices that can
2389	* merge IO requests if the physical pages are ordered
2390	* properly.
2391	*/
2392	if (likely(!cold))
2393	list_add(&page->lru, list);
2394	else
2395	list_add_tail(&page->lru, list);
2396	list = &page->lru;
2397	alloced++;
2398	#ifndef CONFIG_AMLOGIC_MEMORY_EXTEND
2399	if (is_migrate_cma(get_pcppage_migratetype(page)))
2400	__mod_zone_page_state(zone, NR_FREE_CMA_PAGES,
2401	-(1 << order));
2402	#endif /* !CONFIG_AMLOGIC_MEMORY_EXTEND */
2403	}
2404
2405	/*
2406	* i pages were removed from the buddy list even if some leak due
2407	* to check_pcp_refill failing so adjust NR_FREE_PAGES based
2408	* on i. Do not confuse with 'alloced' which is the number of
2409	* pages added to the pcp list.
2410	*/
2411	__mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order));
2412	spin_unlock(&zone->lock);
2413	return alloced;
2414	}
2415
2416	#ifdef CONFIG_NUMA
2417	/*
2418	* Called from the vmstat counter updater to drain pagesets of this
2419	* currently executing processor on remote nodes after they have
2420	* expired.
2421	*
2422	* Note that this function must be called with the thread pinned to
2423	* a single processor.
2424	*/
2425	void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
2426	{
2427	unsigned long flags;
2428	int to_drain, batch;
2429
2430	local_irq_save(flags);
2431	batch = READ_ONCE(pcp->batch);
2432	to_drain = min(pcp->count, batch);
2433	if (to_drain > 0) {
2434	free_pcppages_bulk(zone, to_drain, pcp);
2435	pcp->count -= to_drain;
2436	}
2437	local_irq_restore(flags);
2438	}
2439	#endif
2440
2441	/*
2442	* Drain pcplists of the indicated processor and zone.
2443	*
2444	* The processor must either be the current processor and the
2445	* thread pinned to the current processor or a processor that
2446	* is not online.
2447	*/
2448	static void drain_pages_zone(unsigned int cpu, struct zone *zone)
2449	{
2450	unsigned long flags;
2451	struct per_cpu_pageset *pset;
2452	struct per_cpu_pages *pcp;
2453
2454	local_irq_save(flags);
2455	pset = per_cpu_ptr(zone->pageset, cpu);
2456
2457	pcp = &pset->pcp;
2458	if (pcp->count) {
2459	free_pcppages_bulk(zone, pcp->count, pcp);
2460	pcp->count = 0;
2461	}
2462	local_irq_restore(flags);
2463	}
2464
2465	/*
2466	* Drain pcplists of all zones on the indicated processor.
2467	*
2468	* The processor must either be the current processor and the
2469	* thread pinned to the current processor or a processor that
2470	* is not online.
2471	*/
2472	static void drain_pages(unsigned int cpu)
2473	{
2474	struct zone *zone;
2475
2476	for_each_populated_zone(zone) {
2477	drain_pages_zone(cpu, zone);
2478	}
2479	}
2480
2481	/*
2482	* Spill all of this CPU's per-cpu pages back into the buddy allocator.
2483	*
2484	* The CPU has to be pinned. When zone parameter is non-NULL, spill just
2485	* the single zone's pages.
2486	*/
2487	void drain_local_pages(void *z)
2488	{
2489	struct zone *zone = (struct zone *)z;
2490	int cpu = smp_processor_id();
2491
2492	if (zone)
2493	drain_pages_zone(cpu, zone);
2494	else
2495	drain_pages(cpu);
2496	}
2497
2498	/*
2499	* Spill all the per-cpu pages from all CPUs back into the buddy allocator.
2500	*
2501	* When zone parameter is non-NULL, spill just the single zone's pages.
2502	*
2503	* Note that this code is protected against sending an IPI to an offline
2504	* CPU but does not guarantee sending an IPI to newly hotplugged CPUs:
2505	* on_each_cpu_mask() blocks hotplug and won't talk to offlined CPUs but
2506	* nothing keeps CPUs from showing up after we populated the cpumask and
2507	* before the call to on_each_cpu_mask().
2508	*/
2509	void drain_all_pages(struct zone *zone)
2510	{
2511	int cpu;
2512
2513	/*
2514	* Allocate in the BSS so we wont require allocation in
2515	* direct reclaim path for CONFIG_CPUMASK_OFFSTACK=y
2516	*/
2517	static cpumask_t cpus_with_pcps;
2518
2519	/*
2520	* We don't care about racing with CPU hotplug event
2521	* as offline notification will cause the notified
2522	* cpu to drain that CPU pcps and on_each_cpu_mask
2523	* disables preemption as part of its processing
2524	*/
2525	for_each_online_cpu(cpu) {
2526	struct per_cpu_pageset *pcp;
2527	struct zone *z;
2528	bool has_pcps = false;
2529
2530	if (zone) {
2531	pcp = per_cpu_ptr(zone->pageset, cpu);
2532	if (pcp->pcp.count)
2533	has_pcps = true;
2534	} else {
2535	for_each_populated_zone(z) {
2536	pcp = per_cpu_ptr(z->pageset, cpu);
2537	if (pcp->pcp.count) {
2538	has_pcps = true;
2539	break;
2540	}
2541	}
2542	}
2543
2544	if (has_pcps)
2545	cpumask_set_cpu(cpu, &cpus_with_pcps);
2546	else
2547	cpumask_clear_cpu(cpu, &cpus_with_pcps);
2548	}
2549	on_each_cpu_mask(&cpus_with_pcps, drain_local_pages, zone, 1);
2550	}
2551
2552	#ifdef CONFIG_HIBERNATION
2553
2554	void mark_free_pages(struct zone *zone)
2555	{
2556	unsigned long pfn, max_zone_pfn;
2557	unsigned long flags;
2558	unsigned int order, t;
2559	struct page *page;
2560
2561	if (zone_is_empty(zone))
2562	return;
2563
2564	spin_lock_irqsave(&zone->lock, flags);
2565
2566	max_zone_pfn = zone_end_pfn(zone);
2567	for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
2568	if (pfn_valid(pfn)) {
2569	page = pfn_to_page(pfn);
2570
2571	if (page_zone(page) != zone)
2572	continue;
2573
2574	if (!swsusp_page_is_forbidden(page))
2575	swsusp_unset_page_free(page);
2576	}
2577
2578	for_each_migratetype_order(order, t) {
2579	list_for_each_entry(page,
2580	&zone->free_area[order].free_list[t], lru) {
2581	unsigned long i;
2582
2583	pfn = page_to_pfn(page);
2584	for (i = 0; i < (1UL << order); i++)
2585	swsusp_set_page_free(pfn_to_page(pfn + i));
2586	}
2587	}
2588	spin_unlock_irqrestore(&zone->lock, flags);
2589	}
2590	#endif /* CONFIG_PM */
2591
2592	/*
2593	* Free a 0-order page
2594	* cold == true ? free a cold page : free a hot page
2595	*/
2596	void free_hot_cold_page(struct page *page, bool cold)
2597	{
2598	struct zone *zone = page_zone(page);
2599	struct per_cpu_pages *pcp;
2600	unsigned long flags;
2601	unsigned long pfn = page_to_pfn(page);
2602	int migratetype;
2603
2604	if (!free_pcp_prepare(page))
2605	return;
2606
2607	migratetype = get_pfnblock_migratetype(page, pfn);
2608	set_pcppage_migratetype(page, migratetype);
2609	local_irq_save(flags);
2610	__count_vm_event(PGFREE);
2611
2612	/*
2613	* We only track unmovable, reclaimable and movable on pcp lists.
2614	* Free ISOLATE pages back to the allocator because they are being
2615	* offlined but treat RESERVE as movable pages so we can get those
2616	* areas back if necessary. Otherwise, we may have to free
2617	* excessively into the page allocator
2618	*/
2619	if (migratetype >= MIGRATE_PCPTYPES) {
2620	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
2621	if (unlikely(is_migrate_isolate(migratetype)) ||
2622	unlikely(is_migrate_cma(migratetype))) {
2623	free_one_page(zone, page, pfn, 0, migratetype);
2624	goto out;
2625	}
2626	#else
2627	if (unlikely(is_migrate_isolate(migratetype))) {
2628	free_one_page(zone, page, pfn, 0, migratetype);
2629	goto out;
2630	}
2631	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
2632	migratetype = MIGRATE_MOVABLE;
2633	}
2634
2635	pcp = &this_cpu_ptr(zone->pageset)->pcp;
2636	#if defined(CONFIG_AMLOGIC_MEMORY_EXTEND) && defined(CONFIG_KASAN)
2637	/*
2638	* always put freed page to tail of buddy system, in
2639	* order to increase probability of use-after-free
2640	* for KASAN check.
2641	*/
2642	list_add_tail(&page->lru, &pcp->lists[migratetype]);
2643	#else
2644	if (!cold)
2645	list_add(&page->lru, &pcp->lists[migratetype]);
2646	else
2647	list_add_tail(&page->lru, &pcp->lists[migratetype]);
2648	#endif
2649	pcp->count++;
2650	if (pcp->count >= pcp->high) {
2651	unsigned long batch = READ_ONCE(pcp->batch);
2652	free_pcppages_bulk(zone, batch, pcp);
2653	pcp->count -= batch;
2654	}
2655
2656	out:
2657	local_irq_restore(flags);
2658	}
2659
2660	/*
2661	* Free a list of 0-order pages
2662	*/
2663	void free_hot_cold_page_list(struct list_head *list, bool cold)
2664	{
2665	struct page *page, *next;
2666
2667	list_for_each_entry_safe(page, next, list, lru) {
2668	trace_mm_page_free_batched(page, cold);
2669	free_hot_cold_page(page, cold);
2670	}
2671	}
2672
2673	/*
2674	* split_page takes a non-compound higher-order page, and splits it into
2675	* n (1<<order) sub-pages: page[0..n]
2676	* Each sub-page must be freed individually.
2677	*
2678	* Note: this is probably too low level an operation for use in drivers.
2679	* Please consult with lkml before using this in your driver.
2680	*/
2681	void split_page(struct page *page, unsigned int order)
2682	{
2683	int i;
2684
2685	VM_BUG_ON_PAGE(PageCompound(page), page);
2686	VM_BUG_ON_PAGE(!page_count(page), page);
2687
2688	#ifdef CONFIG_KMEMCHECK
2689	/*
2690	* Split shadow pages too, because free(page[0]) would
2691	* otherwise free the whole shadow.
2692	*/
2693	if (kmemcheck_page_is_tracked(page))
2694	split_page(virt_to_page(page[0].shadow), order);
2695	#endif
2696
2697	for (i = 1; i < (1 << order); i++)
2698	set_page_refcounted(page + i);
2699	split_page_owner(page, order);
2700	}
2701	EXPORT_SYMBOL_GPL(split_page);
2702
2703	int __isolate_free_page(struct page *page, unsigned int order)
2704	{
2705	unsigned long watermark;
2706	struct zone *zone;
2707	int mt;
2708
2709	BUG_ON(!PageBuddy(page));
2710
2711	zone = page_zone(page);
2712	mt = get_pageblock_migratetype(page);
2713
2714	if (!is_migrate_isolate(mt)) {
2715	/*
2716	* Obey watermarks as if the page was being allocated. We can
2717	* emulate a high-order watermark check with a raised order-0
2718	* watermark, because we already know our high-order page
2719	* exists.
2720	*/
2721	watermark = min_wmark_pages(zone) + (1UL << order);
2722	if (!zone_watermark_ok(zone, 0, watermark, 0, ALLOC_CMA))
2723	return 0;
2724
2725	__mod_zone_freepage_state(zone, -(1UL << order), mt);
2726	}
2727
2728	/* Remove page from free list */
2729	list_del(&page->lru);
2730	zone->free_area[order].nr_free--;
2731	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
2732	__mod_zone_migrate_state(zone, -(1 << order),
2733	get_pcppage_migratetype(page));
2734	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
2735	rmv_page_order(page);
2736
2737	/*
2738	* Set the pageblock if the isolated page is at least half of a
2739	* pageblock
2740	*/
2741	if (order >= pageblock_order - 1) {
2742	struct page *endpage = page + (1 << order) - 1;
2743	for (; page < endpage; page += pageblock_nr_pages) {
2744	int mt = get_pageblock_migratetype(page);
2745	if (!is_migrate_isolate(mt) && !is_migrate_cma(mt))
2746	set_pageblock_migratetype(page,
2747	MIGRATE_MOVABLE);
2748	}
2749	}
2750
2751
2752	return 1UL << order;
2753	}
2754
2755	/*
2756	* Update NUMA hit/miss statistics
2757	*
2758	* Must be called with interrupts disabled.
2759	*/
2760	static inline void zone_statistics(struct zone *preferred_zone, struct zone *z,
2761	gfp_t flags)
2762	{
2763	#ifdef CONFIG_NUMA
2764	enum zone_stat_item local_stat = NUMA_LOCAL;
2765
2766	if (z->node != numa_node_id())
2767	local_stat = NUMA_OTHER;
2768
2769	if (z->node == preferred_zone->node)
2770	__inc_zone_state(z, NUMA_HIT);
2771	else {
2772	__inc_zone_state(z, NUMA_MISS);
2773	__inc_zone_state(preferred_zone, NUMA_FOREIGN);
2774	}
2775	__inc_zone_state(z, local_stat);
2776	#endif
2777	}
2778
2779	/*
2780	* Allocate a page from the given zone. Use pcplists for order-0 allocations.
2781	*/
2782	static inline
2783	struct page *buffered_rmqueue(struct zone *preferred_zone,
2784	struct zone *zone, unsigned int order,
2785	gfp_t gfp_flags, unsigned int alloc_flags,
2786	int migratetype)
2787	{
2788	unsigned long flags;
2789	struct page *page;
2790	bool cold = ((gfp_flags & __GFP_COLD) != 0);
2791	#ifdef CONFIG_AMLOGIC_CMA
2792	bool cma = can_use_cma(gfp_flags);
2793	#endif
2794
2795	if (likely(order == 0)) {
2796	struct per_cpu_pages *pcp;
2797	struct list_head *list;
2798
2799	local_irq_save(flags);
2800	do {
2801	pcp = &this_cpu_ptr(zone->pageset)->pcp;
2802	list = &pcp->lists[migratetype];
2803	if (list_empty(list)) {
2804	#ifdef CONFIG_AMLOGIC_CMA
2805	pcp->count += rmqueue_bulk(zone, 0,
2806	pcp->batch, list,
2807	migratetype, cold,
2808	cma);
2809	#else
2810	pcp->count += rmqueue_bulk(zone, 0,
2811	pcp->batch, list,
2812	migratetype, cold);
2813	#endif /* CONFIG_AMLOGIC_CMA */
2814	if (unlikely(list_empty(list)))
2815	goto failed;
2816	}
2817
2818	if (cold)
2819	page = list_last_entry(list, struct page, lru);
2820	else
2821	page = list_first_entry(list, struct page, lru);
2822
2823	#ifdef CONFIG_AMLOGIC_CMA
2824	/*
2825	* USING CMA FIRST POLICY situations:
2826	* 1. CMA pages may return to pcp and allocated next
2827	* but gfp mask is not suitable for CMA;
2828	* 2. MOVABLE pages may return to pcp and allocated next
2829	* but gfp mask is suitable for CMA
2830	*
2831	* For 1, we should replace a none-CMA page
2832	* For 2, we should replace with a cma page
2833	* before page is deleted from PCP list.
2834	*/
2835	if (!cma && is_migrate_cma_page(page)) {
2836	/* case 1 */
2837	page = rmqueue_no_cma(zone, order, migratetype);
2838	if (page)
2839	break;
2840	goto failed;
2841	} else if ((migratetype == MIGRATE_MOVABLE) &&
2842	(get_pcppage_migratetype(page) != MIGRATE_CMA) &&
2843	cma) {
2844	struct page *tmp_page;
2845
2846	spin_lock(&zone->lock);
2847	tmp_page = __rmqueue_cma_fallback(zone, order);
2848	/* can't alloc cma pages or not ready */
2849	if (!tmp_page || check_new_pcp(page)) {
2850	spin_unlock(&zone->lock);
2851	goto use_pcp;
2852	}
2853	page = tmp_page;
2854	__mod_zone_freepage_state(zone, -(1 << order),
2855	get_pcppage_migratetype(page));
2856	spin_unlock(&zone->lock);
2857	goto alloc_success;
2858	}
2859	use_pcp:
2860	#endif /* CONFIG_AMLOGIC_CMA */
2861
2862	list_del(&page->lru);
2863	pcp->count--;
2864
2865	} while (check_new_pcp(page));
2866	} else {
2867	/*
2868	* We most definitely don't want callers attempting to
2869	* allocate greater than order-1 page units with __GFP_NOFAIL.
2870	*/
2871	WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1));
2872	spin_lock_irqsave(&zone->lock, flags);
2873
2874	do {
2875	page = NULL;
2876	if (alloc_flags & ALLOC_HARDER) {
2877	page = __rmqueue_smallest(zone, order, MIGRATE_HIGHATOMIC);
2878	if (page)
2879	trace_mm_page_alloc_zone_locked(page, order, migratetype);
2880	}
2881	if (!page)
2882	#ifdef CONFIG_AMLOGIC_CMA
2883	page = __rmqueue(zone, order,
2884	migratetype, cma);
2885	#else
2886	page = __rmqueue(zone, order, migratetype);
2887	#endif /* CONFIG_AMLOGIC_CMA */
2888	} while (page && check_new_pages(page, order));
2889	spin_unlock(&zone->lock);
2890	if (!page)
2891	goto failed;
2892	__mod_zone_freepage_state(zone, -(1 << order),
2893	get_pcppage_migratetype(page));
2894	}
2895
2896	#ifdef CONFIG_AMLOGIC_CMA
2897	alloc_success:
2898	#endif /* CONFIG_AMLOGIC_CMA */
2899	__count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order);
2900	zone_statistics(preferred_zone, zone, gfp_flags);
2901	local_irq_restore(flags);
2902
2903	VM_BUG_ON_PAGE(bad_range(zone, page), page);
2904	return page;
2905
2906	failed:
2907	local_irq_restore(flags);
2908	return NULL;
2909	}
2910
2911	#ifdef CONFIG_FAIL_PAGE_ALLOC
2912
2913	static struct {
2914	struct fault_attr attr;
2915
2916	bool ignore_gfp_highmem;
2917	bool ignore_gfp_reclaim;
2918	u32 min_order;
2919	} fail_page_alloc = {
2920	.attr = FAULT_ATTR_INITIALIZER,
2921	.ignore_gfp_reclaim = true,
2922	.ignore_gfp_highmem = true,
2923	.min_order = 1,
2924	};
2925
2926	static int __init setup_fail_page_alloc(char *str)
2927	{
2928	return setup_fault_attr(&fail_page_alloc.attr, str);
2929	}
2930	__setup("fail_page_alloc=", setup_fail_page_alloc);
2931
2932	static bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
2933	{
2934	if (order < fail_page_alloc.min_order)
2935	return false;
2936	if (gfp_mask & __GFP_NOFAIL)
2937	return false;
2938	if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM))
2939	return false;
2940	if (fail_page_alloc.ignore_gfp_reclaim &&
2941	(gfp_mask & __GFP_DIRECT_RECLAIM))
2942	return false;
2943
2944	return should_fail(&fail_page_alloc.attr, 1 << order);
2945	}
2946
2947	#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
2948
2949	static int __init fail_page_alloc_debugfs(void)
2950	{
2951	umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
2952	struct dentry *dir;
2953
2954	dir = fault_create_debugfs_attr("fail_page_alloc", NULL,
2955	&fail_page_alloc.attr);
2956	if (IS_ERR(dir))
2957	return PTR_ERR(dir);
2958
2959	if (!debugfs_create_bool("ignore-gfp-wait", mode, dir,
2960	&fail_page_alloc.ignore_gfp_reclaim))
2961	goto fail;
2962	if (!debugfs_create_bool("ignore-gfp-highmem", mode, dir,
2963	&fail_page_alloc.ignore_gfp_highmem))
2964	goto fail;
2965	if (!debugfs_create_u32("min-order", mode, dir,
2966	&fail_page_alloc.min_order))
2967	goto fail;
2968
2969	return 0;
2970	fail:
2971	debugfs_remove_recursive(dir);
2972
2973	return -ENOMEM;
2974	}
2975
2976	late_initcall(fail_page_alloc_debugfs);
2977
2978	#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
2979
2980	#else /* CONFIG_FAIL_PAGE_ALLOC */
2981
2982	static inline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
2983	{
2984	return false;
2985	}
2986
2987	#endif /* CONFIG_FAIL_PAGE_ALLOC */
2988
2989	/*
2990	* Return true if free base pages are above 'mark'. For high-order checks it
2991	* will return true of the order-0 watermark is reached and there is at least
2992	* one free page of a suitable size. Checking now avoids taking the zone lock
2993	* to check in the allocation paths if no pages are free.
2994	*/
2995	bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
2996	int classzone_idx, unsigned int alloc_flags,
2997	long free_pages)
2998	{
2999	long min = mark;
3000	int o;
3001	const bool alloc_harder = (alloc_flags & ALLOC_HARDER);
3002
3003	/* free_pages may go negative - that's OK */
3004	free_pages -= (1 << order) - 1;
3005
3006	if (alloc_flags & ALLOC_HIGH)
3007	min -= min / 2;
3008
3009	/*
3010	* If the caller does not have rights to ALLOC_HARDER then subtract
3011	* the high-atomic reserves. This will over-estimate the size of the
3012	* atomic reserve but it avoids a search.
3013	*/
3014	if (likely(!alloc_harder))
3015	free_pages -= z->nr_reserved_highatomic;
3016	else
3017	min -= min / 4;
3018
3019	#ifdef CONFIG_CMA
3020	/* If allocation can't use CMA areas don't use free CMA pages */
3021	#ifndef CONFIG_AMLOGIC_CMA /* always sub cma pages to avoid wm all CMA */
3022	if (!(alloc_flags & ALLOC_CMA))
3023	#endif
3024	free_pages -= zone_page_state(z, NR_FREE_CMA_PAGES);
3025	#endif
3026
3027	/*
3028	* Check watermarks for an order-0 allocation request. If these
3029	* are not met, then a high-order request also cannot go ahead
3030	* even if a suitable page happened to be free.
3031	*/
3032	#ifdef CONFIG_AMLOGIC_CMA
3033	if (free_pages <= min + z->lowmem_reserve[classzone_idx]) {
3034	/* do not using cma until water mark is low */
3035	if (unlikely(!cma_first_wm_low && free_pages > 0)) {
3036	cma_first_wm_low = true;
3037	pr_info("Now can use cma, free:%ld, wm:%ld\n",
3038	free_pages,
3039	min + z->lowmem_reserve[classzone_idx]);
3040	}
3041	return false;
3042	}
3043	#else
3044	if (free_pages <= min + z->lowmem_reserve[classzone_idx])
3045	return false;
3046	#endif
3047
3048	/* If this is an order-0 request then the watermark is fine */
3049	if (!order)
3050	return true;
3051
3052	/* For a high-order request, check at least one suitable page is free */
3053	for (o = order; o < MAX_ORDER; o++) {
3054	struct free_area *area = &z->free_area[o];
3055	int mt;
3056
3057	if (!area->nr_free)
3058	continue;
3059
3060	for (mt = 0; mt < MIGRATE_PCPTYPES; mt++) {
3061	if (!list_empty(&area->free_list[mt]))
3062	return true;
3063	}
3064
3065	#ifdef CONFIG_CMA
3066	if ((alloc_flags & ALLOC_CMA) &&
3067	!list_empty(&area->free_list[MIGRATE_CMA])) {
3068	return true;
3069	}
3070	#endif
3071	if (alloc_harder &&
3072	!list_empty(&area->free_list[MIGRATE_HIGHATOMIC]))
3073	return true;
3074	}
3075	return false;
3076	}
3077
3078	bool zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
3079	int classzone_idx, unsigned int alloc_flags)
3080	{
3081	return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags,
3082	zone_page_state(z, NR_FREE_PAGES));
3083	}
3084
3085	static inline bool zone_watermark_fast(struct zone *z, unsigned int order,
3086	unsigned long mark, int classzone_idx, unsigned int alloc_flags)
3087	{
3088	long free_pages = zone_page_state(z, NR_FREE_PAGES);
3089	long cma_pages = 0;
3090
3091	#ifdef CONFIG_CMA
3092	/* If allocation can't use CMA areas don't use free CMA pages */
3093	if (!(alloc_flags & ALLOC_CMA))
3094	cma_pages = zone_page_state(z, NR_FREE_CMA_PAGES);
3095	#endif
3096
3097	/*
3098	* Fast check for order-0 only. If this fails then the reserves
3099	* need to be calculated. There is a corner case where the check
3100	* passes but only the high-order atomic reserve are free. If
3101	* the caller is !atomic then it'll uselessly search the free
3102	* list. That corner case is then slower but it is harmless.
3103	*/
3104	if (!order && (free_pages - cma_pages) > mark + z->lowmem_reserve[classzone_idx])
3105	return true;
3106
3107	return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags,
3108	free_pages);
3109	}
3110
3111	bool zone_watermark_ok_safe(struct zone *z, unsigned int order,
3112	unsigned long mark, int classzone_idx)
3113	{
3114	long free_pages = zone_page_state(z, NR_FREE_PAGES);
3115
3116	if (z->percpu_drift_mark && free_pages < z->percpu_drift_mark)
3117	free_pages = zone_page_state_snapshot(z, NR_FREE_PAGES);
3118
3119	return __zone_watermark_ok(z, order, mark, classzone_idx, 0,
3120	free_pages);
3121	}
3122
3123	#ifdef CONFIG_NUMA
3124	static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone)
3125	{
3126	return node_distance(zone_to_nid(local_zone), zone_to_nid(zone)) <=
3127	RECLAIM_DISTANCE;
3128	}
3129	#else /* CONFIG_NUMA */
3130	static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone)
3131	{
3132	return true;
3133	}
3134	#endif /* CONFIG_NUMA */
3135
3136	/*
3137	* get_page_from_freelist goes through the zonelist trying to allocate
3138	* a page.
3139	*/
3140	static struct page *
3141	get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags,
3142	const struct alloc_context *ac)
3143	{
3144	struct zoneref *z = ac->preferred_zoneref;
3145	struct zone *zone;
3146	struct pglist_data *last_pgdat_dirty_limit = NULL;
3147
3148	/*
3149	* Scan zonelist, looking for a zone with enough free.
3150	* See also __cpuset_node_allowed() comment in kernel/cpuset.c.
3151	*/
3152	for_next_zone_zonelist_nodemask(zone, z, ac->zonelist, ac->high_zoneidx,
3153	ac->nodemask) {
3154	struct page *page;
3155	unsigned long mark;
3156
3157	if (cpusets_enabled() &&
3158	(alloc_flags & ALLOC_CPUSET) &&
3159	!__cpuset_zone_allowed(zone, gfp_mask))
3160	continue;
3161	/*
3162	* When allocating a page cache page for writing, we
3163	* want to get it from a node that is within its dirty
3164	* limit, such that no single node holds more than its
3165	* proportional share of globally allowed dirty pages.
3166	* The dirty limits take into account the node's
3167	* lowmem reserves and high watermark so that kswapd
3168	* should be able to balance it without having to
3169	* write pages from its LRU list.
3170	*
3171	* XXX: For now, allow allocations to potentially
3172	* exceed the per-node dirty limit in the slowpath
3173	* (spread_dirty_pages unset) before going into reclaim,
3174	* which is important when on a NUMA setup the allowed
3175	* nodes are together not big enough to reach the
3176	* global limit. The proper fix for these situations
3177	* will require awareness of nodes in the
3178	* dirty-throttling and the flusher threads.
3179	*/
3180	if (ac->spread_dirty_pages) {
3181	if (last_pgdat_dirty_limit == zone->zone_pgdat)
3182	continue;
3183
3184	if (!node_dirty_ok(zone->zone_pgdat)) {
3185	last_pgdat_dirty_limit = zone->zone_pgdat;
3186	continue;
3187	}
3188	}
3189
3190	mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK];
3191	if (!zone_watermark_fast(zone, order, mark,
3192	ac_classzone_idx(ac), alloc_flags)) {
3193	int ret;
3194
3195	/* Checked here to keep the fast path fast */
3196	BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK);
3197	if (alloc_flags & ALLOC_NO_WATERMARKS)
3198	goto try_this_zone;
3199
3200	if (node_reclaim_mode == 0 ||
3201	!zone_allows_reclaim(ac->preferred_zoneref->zone, zone))
3202	continue;
3203
3204	ret = node_reclaim(zone->zone_pgdat, gfp_mask, order);
3205	switch (ret) {
3206	case NODE_RECLAIM_NOSCAN:
3207	/* did not scan */
3208	continue;
3209	case NODE_RECLAIM_FULL:
3210	/* scanned but unreclaimable */
3211	continue;
3212	default:
3213	/* did we reclaim enough */
3214	if (zone_watermark_ok(zone, order, mark,
3215	ac_classzone_idx(ac), alloc_flags))
3216	goto try_this_zone;
3217
3218	continue;
3219	}
3220	}
3221
3222	try_this_zone:
3223	page = buffered_rmqueue(ac->preferred_zoneref->zone, zone, order,
3224	gfp_mask, alloc_flags, ac->migratetype);
3225	if (page) {
3226	prep_new_page(page, order, gfp_mask, alloc_flags);
3227
3228	/*
3229	* If this is a high-order atomic allocation then check
3230	* if the pageblock should be reserved for the future
3231	*/
3232	if (unlikely(order && (alloc_flags & ALLOC_HARDER)))
3233	reserve_highatomic_pageblock(page, zone, order);
3234
3235	return page;
3236	}
3237	}
3238
3239	return NULL;
3240	}
3241
3242	/*
3243	* Large machines with many possible nodes should not always dump per-node
3244	* meminfo in irq context.
3245	*/
3246	static inline bool should_suppress_show_mem(void)
3247	{
3248	bool ret = false;
3249
3250	#if NODES_SHIFT > 8
3251	ret = in_interrupt();
3252	#endif
3253	return ret;
3254	}
3255
3256	static DEFINE_RATELIMIT_STATE(nopage_rs,
3257	DEFAULT_RATELIMIT_INTERVAL,
3258	DEFAULT_RATELIMIT_BURST);
3259
3260	void warn_alloc(gfp_t gfp_mask, const char *fmt, ...)
3261	{
3262	unsigned int filter = SHOW_MEM_FILTER_NODES;
3263	struct va_format vaf;
3264	va_list args;
3265
3266	if ((gfp_mask & __GFP_NOWARN) || !__ratelimit(&nopage_rs) ||
3267	debug_guardpage_minorder() > 0)
3268	return;
3269
3270	/*
3271	* This documents exceptions given to allocations in certain
3272	* contexts that are allowed to allocate outside current's set
3273	* of allowed nodes.
3274	*/
3275	if (!(gfp_mask & __GFP_NOMEMALLOC))
3276	if (test_thread_flag(TIF_MEMDIE) ||
3277	(current->flags & (PF_MEMALLOC | PF_EXITING)))
3278	filter &= ~SHOW_MEM_FILTER_NODES;
3279	if (in_interrupt() || !(gfp_mask & __GFP_DIRECT_RECLAIM))
3280	filter &= ~SHOW_MEM_FILTER_NODES;
3281
3282	pr_warn("%s: ", current->comm);
3283
3284	va_start(args, fmt);
3285	vaf.fmt = fmt;
3286	vaf.va = &args;
3287	pr_cont("%pV", &vaf);
3288	va_end(args);
3289
3290	pr_cont(", mode:%#x(%pGg)\n", gfp_mask, &gfp_mask);
3291
3292	dump_stack();
3293	if (!should_suppress_show_mem())
3294	show_mem(filter);
3295	}
3296
3297	static inline struct page *
3298	__alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
3299	const struct alloc_context *ac, unsigned long *did_some_progress)
3300	{
3301	struct oom_control oc = {
3302	.zonelist = ac->zonelist,
3303	.nodemask = ac->nodemask,
3304	.memcg = NULL,
3305	.gfp_mask = gfp_mask,
3306	.order = order,
3307	};
3308	struct page *page;
3309
3310	*did_some_progress = 0;
3311
3312	/*
3313	* Acquire the oom lock. If that fails, somebody else is
3314	* making progress for us.
3315	*/
3316	if (!mutex_trylock(&oom_lock)) {
3317	*did_some_progress = 1;
3318	schedule_timeout_uninterruptible(1);
3319	return NULL;
3320	}
3321
3322	/*
3323	* Go through the zonelist yet one more time, keep very high watermark
3324	* here, this is only to catch a parallel oom killing, we must fail if
3325	* we're still under heavy pressure.
3326	*/
3327	page = get_page_from_freelist(gfp_mask | __GFP_HARDWALL, order,
3328	ALLOC_WMARK_HIGH|ALLOC_CPUSET, ac);
3329	if (page)
3330	goto out;
3331
3332	if (!(gfp_mask & __GFP_NOFAIL)) {
3333	/* Coredumps can quickly deplete all memory reserves */
3334	if (current->flags & PF_DUMPCORE)
3335	goto out;
3336	/* The OOM killer will not help higher order allocs */
3337	if (order > PAGE_ALLOC_COSTLY_ORDER)
3338	goto out;
3339	/* The OOM killer does not needlessly kill tasks for lowmem */
3340	if (ac->high_zoneidx < ZONE_NORMAL)
3341	goto out;
3342	if (pm_suspended_storage())
3343	goto out;
3344	/*
3345	* XXX: GFP_NOFS allocations should rather fail than rely on
3346	* other request to make a forward progress.
3347	* We are in an unfortunate situation where out_of_memory cannot
3348	* do much for this context but let's try it to at least get
3349	* access to memory reserved if the current task is killed (see
3350	* out_of_memory). Once filesystems are ready to handle allocation
3351	* failures more gracefully we should just bail out here.
3352	*/
3353
3354	/* The OOM killer may not free memory on a specific node */
3355	if (gfp_mask & __GFP_THISNODE)
3356	goto out;
3357	}
3358	/* Exhausted what can be done so it's blamo time */
3359	if (out_of_memory(&oc) || WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL)) {
3360	*did_some_progress = 1;
3361
3362	if (gfp_mask & __GFP_NOFAIL) {
3363	page = get_page_from_freelist(gfp_mask, order,
3364	ALLOC_NO_WATERMARKS|ALLOC_CPUSET, ac);
3365	/*
3366	* fallback to ignore cpuset restriction if our nodes
3367	* are depleted
3368	*/
3369	if (!page)
3370	page = get_page_from_freelist(gfp_mask, order,
3371	ALLOC_NO_WATERMARKS, ac);
3372	}
3373	}
3374	out:
3375	mutex_unlock(&oom_lock);
3376	return page;
3377	}
3378
3379	/*
3380	* Maximum number of compaction retries wit a progress before OOM
3381	* killer is consider as the only way to move forward.
3382	*/
3383	#define MAX_COMPACT_RETRIES 16
3384
3385	#ifdef CONFIG_COMPACTION
3386	/* Try memory compaction for high-order allocations before reclaim */
3387	static struct page *
3388	__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
3389	unsigned int alloc_flags, const struct alloc_context *ac,
3390	enum compact_priority prio, enum compact_result *compact_result)
3391	{
3392	struct page *page;
3393	unsigned long pflags;
3394	unsigned int noreclaim_flag = current->flags & PF_MEMALLOC;
3395
3396	if (!order)
3397	return NULL;
3398
3399	psi_memstall_enter(&pflags);
3400	current->flags |= PF_MEMALLOC;
3401
3402	*compact_result = try_to_compact_pages(gfp_mask, order, alloc_flags, ac,
3403	prio);
3404
3405	current->flags = (current->flags & ~PF_MEMALLOC) | noreclaim_flag;
3406	psi_memstall_leave(&pflags);
3407
3408	if (*compact_result <= COMPACT_INACTIVE)
3409	return NULL;
3410
3411	/*
3412	* At least in one zone compaction wasn't deferred or skipped, so let's
3413	* count a compaction stall
3414	*/
3415	count_vm_event(COMPACTSTALL);
3416
3417	page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac);
3418
3419	if (page) {
3420	struct zone *zone = page_zone(page);
3421
3422	zone->compact_blockskip_flush = false;
3423	compaction_defer_reset(zone, order, true);
3424	count_vm_event(COMPACTSUCCESS);
3425	return page;
3426	}
3427
3428	/*
3429	* It's bad if compaction run occurs and fails. The most likely reason
3430	* is that pages exist, but not enough to satisfy watermarks.
3431	*/
3432	count_vm_event(COMPACTFAIL);
3433
3434	cond_resched();
3435
3436	return NULL;
3437	}
3438
3439	static inline bool
3440	should_compact_retry(struct alloc_context *ac, int order, int alloc_flags,
3441	enum compact_result compact_result,
3442	enum compact_priority *compact_priority,
3443	int *compaction_retries)
3444	{
3445	int max_retries = MAX_COMPACT_RETRIES;
3446	int min_priority;
3447
3448	if (!order)
3449	return false;
3450
3451	if (compaction_made_progress(compact_result))
3452	(*compaction_retries)++;
3453
3454	/*
3455	* compaction considers all the zone as desperately out of memory
3456	* so it doesn't really make much sense to retry except when the
3457	* failure could be caused by insufficient priority
3458	*/
3459	if (compaction_failed(compact_result))
3460	goto check_priority;
3461
3462	/*
3463	* make sure the compaction wasn't deferred or didn't bail out early
3464	* due to locks contention before we declare that we should give up.
3465	* But do not retry if the given zonelist is not suitable for
3466	* compaction.
3467	*/
3468	if (compaction_withdrawn(compact_result))
3469	return compaction_zonelist_suitable(ac, order, alloc_flags);
3470
3471	/*
3472	* !costly requests are much more important than __GFP_REPEAT
3473	* costly ones because they are de facto nofail and invoke OOM
3474	* killer to move on while costly can fail and users are ready
3475	* to cope with that. 1/4 retries is rather arbitrary but we
3476	* would need much more detailed feedback from compaction to
3477	* make a better decision.
3478	*/
3479	if (order > PAGE_ALLOC_COSTLY_ORDER)
3480	max_retries /= 4;
3481	if (*compaction_retries <= max_retries)
3482	return true;
3483
3484	/*
3485	* Make sure there are attempts at the highest priority if we exhausted
3486	* all retries or failed at the lower priorities.
3487	*/
3488	check_priority:
3489	min_priority = (order > PAGE_ALLOC_COSTLY_ORDER) ?
3490	MIN_COMPACT_COSTLY_PRIORITY : MIN_COMPACT_PRIORITY;
3491	if (*compact_priority > min_priority) {
3492	(*compact_priority)--;
3493	*compaction_retries = 0;
3494	return true;
3495	}
3496	return false;
3497	}
3498	#else
3499	static inline struct page *
3500	__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
3501	unsigned int alloc_flags, const struct alloc_context *ac,
3502	enum compact_priority prio, enum compact_result *compact_result)
3503	{
3504	*compact_result = COMPACT_SKIPPED;
3505	return NULL;
3506	}
3507
3508	static inline bool
3509	should_compact_retry(struct alloc_context *ac, unsigned int order, int alloc_flags,
3510	enum compact_result compact_result,
3511	enum compact_priority *compact_priority,
3512	int *compaction_retries)
3513	{
3514	struct zone *zone;
3515	struct zoneref *z;
3516
3517	if (!order || order > PAGE_ALLOC_COSTLY_ORDER)
3518	return false;
3519
3520	/*
3521	* There are setups with compaction disabled which would prefer to loop
3522	* inside the allocator rather than hit the oom killer prematurely.
3523	* Let's give them a good hope and keep retrying while the order-0
3524	* watermarks are OK.
3525	*/
3526	for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, ac->high_zoneidx,
3527	ac->nodemask) {
3528	if (zone_watermark_ok(zone, 0, min_wmark_pages(zone),
3529	ac_classzone_idx(ac), alloc_flags))
3530	return true;
3531	}
3532	return false;
3533	}
3534	#endif /* CONFIG_COMPACTION */
3535
3536	/* Perform direct synchronous page reclaim */
3537	static int
3538	__perform_reclaim(gfp_t gfp_mask, unsigned int order,
3539	const struct alloc_context *ac)
3540	{
3541	struct reclaim_state reclaim_state;
3542	int progress;
3543	unsigned long pflags;
3544
3545	cond_resched();
3546
3547	/* We now go into synchronous reclaim */
3548	cpuset_memory_pressure_bump();
3549	psi_memstall_enter(&pflags);
3550	current->flags |= PF_MEMALLOC;
3551	lockdep_set_current_reclaim_state(gfp_mask);
3552	reclaim_state.reclaimed_slab = 0;
3553	current->reclaim_state = &reclaim_state;
3554
3555	progress = try_to_free_pages(ac->zonelist, order, gfp_mask,
3556	ac->nodemask);
3557
3558	current->reclaim_state = NULL;
3559	lockdep_clear_current_reclaim_state();
3560	current->flags &= ~PF_MEMALLOC;
3561	psi_memstall_leave(&pflags);
3562
3563	cond_resched();
3564
3565	return progress;
3566	}
3567
3568	/* The really slow allocator path where we enter direct reclaim */
3569	static inline struct page *
3570	__alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
3571	unsigned int alloc_flags, const struct alloc_context *ac,
3572	unsigned long *did_some_progress)
3573	{
3574	struct page *page = NULL;
3575	bool drained = false;
3576
3577	*did_some_progress = __perform_reclaim(gfp_mask, order, ac);
3578	if (unlikely(!(*did_some_progress)))
3579	return NULL;
3580
3581	retry:
3582	page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac);
3583
3584	/*
3585	* If an allocation failed after direct reclaim, it could be because
3586	* pages are pinned on the per-cpu lists or in high alloc reserves.
3587	* Shrink them them and try again
3588	*/
3589	if (!page && !drained) {
3590	unreserve_highatomic_pageblock(ac);
3591	drain_all_pages(NULL);
3592	drained = true;
3593	goto retry;
3594	}
3595
3596	return page;
3597	}
3598
3599	static void wake_all_kswapds(unsigned int order, const struct alloc_context *ac)
3600	{
3601	struct zoneref *z;
3602	struct zone *zone;
3603	pg_data_t *last_pgdat = NULL;
3604
3605	for_each_zone_zonelist_nodemask(zone, z, ac->zonelist,
3606	ac->high_zoneidx, ac->nodemask) {
3607	if (last_pgdat != zone->zone_pgdat)
3608	wakeup_kswapd(zone, order, ac->high_zoneidx);
3609	last_pgdat = zone->zone_pgdat;
3610	}
3611	}
3612
3613	static inline unsigned int
3614	gfp_to_alloc_flags(gfp_t gfp_mask)
3615	{
3616	unsigned int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET;
3617
3618	/* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
3619	BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_HIGH);
3620
3621	/*
3622	* The caller may dip into page reserves a bit more if the caller
3623	* cannot run direct reclaim, or if the caller has realtime scheduling
3624	* policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
3625	* set both ALLOC_HARDER (__GFP_ATOMIC) and ALLOC_HIGH (__GFP_HIGH).
3626	*/
3627	alloc_flags |= (__force int) (gfp_mask & __GFP_HIGH);
3628
3629	if (gfp_mask & __GFP_ATOMIC) {
3630	/*
3631	* Not worth trying to allocate harder for __GFP_NOMEMALLOC even
3632	* if it can't schedule.
3633	*/
3634	if (!(gfp_mask & __GFP_NOMEMALLOC))
3635	alloc_flags |= ALLOC_HARDER;
3636	/*
3637	* Ignore cpuset mems for GFP_ATOMIC rather than fail, see the
3638	* comment for __cpuset_node_allowed().
3639	*/
3640	alloc_flags &= ~ALLOC_CPUSET;
3641	} else if (unlikely(rt_task(current)) && !in_interrupt())
3642	alloc_flags |= ALLOC_HARDER;
3643
3644	#ifdef CONFIG_CMA
3645	if (gfpflags_to_migratetype(gfp_mask) == MIGRATE_MOVABLE)
3646	alloc_flags |= ALLOC_CMA;
3647	#endif
3648	return alloc_flags;
3649	}
3650
3651	bool gfp_pfmemalloc_allowed(gfp_t gfp_mask)
3652	{
3653	if (unlikely(gfp_mask & __GFP_NOMEMALLOC))
3654	return false;
3655
3656	if (gfp_mask & __GFP_MEMALLOC)
3657	return true;
3658	if (in_serving_softirq() && (current->flags & PF_MEMALLOC))
3659	return true;
3660	if (!in_interrupt() &&
3661	((current->flags & PF_MEMALLOC) ||
3662	unlikely(test_thread_flag(TIF_MEMDIE))))
3663	return true;
3664
3665	return false;
3666	}
3667
3668	/*
3669	* Checks whether it makes sense to retry the reclaim to make a forward progress
3670	* for the given allocation request.
3671	* The reclaim feedback represented by did_some_progress (any progress during
3672	* the last reclaim round) and no_progress_loops (number of reclaim rounds without
3673	* any progress in a row) is considered as well as the reclaimable pages on the
3674	* applicable zone list (with a backoff mechanism which is a function of
3675	* no_progress_loops).
3676	*
3677	* Returns true if a retry is viable or false to enter the oom path.
3678	*/
3679	static inline bool
3680	should_reclaim_retry(gfp_t gfp_mask, unsigned order,
3681	struct alloc_context *ac, int alloc_flags,
3682	bool did_some_progress, int *no_progress_loops)
3683	{
3684	struct zone *zone;
3685	struct zoneref *z;
3686
3687	/*
3688	* Costly allocations might have made a progress but this doesn't mean
3689	* their order will become available due to high fragmentation so
3690	* always increment the no progress counter for them
3691	*/
3692	if (did_some_progress && order <= PAGE_ALLOC_COSTLY_ORDER)
3693	*no_progress_loops = 0;
3694	else
3695	(*no_progress_loops)++;
3696
3697	/*
3698	* Make sure we converge to OOM if we cannot make any progress
3699	* several times in the row.
3700	*/
3701	if (*no_progress_loops > MAX_RECLAIM_RETRIES)
3702	return false;
3703
3704	/*
3705	* Keep reclaiming pages while there is a chance this will lead
3706	* somewhere. If none of the target zones can satisfy our allocation
3707	* request even if all reclaimable pages are considered then we are
3708	* screwed and have to go OOM.
3709	*/
3710	for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, ac->high_zoneidx,
3711	ac->nodemask) {
3712	unsigned long available;
3713	unsigned long reclaimable;
3714
3715	available = reclaimable = zone_reclaimable_pages(zone);
3716	available -= DIV_ROUND_UP((*no_progress_loops) * available,
3717	MAX_RECLAIM_RETRIES);
3718	available += zone_page_state_snapshot(zone, NR_FREE_PAGES);
3719
3720	/*
3721	* Would the allocation succeed if we reclaimed the whole
3722	* available?
3723	*/
3724	if (__zone_watermark_ok(zone, order, min_wmark_pages(zone),
3725	ac_classzone_idx(ac), alloc_flags, available)) {
3726	/*
3727	* If we didn't make any progress and have a lot of
3728	* dirty + writeback pages then we should wait for
3729	* an IO to complete to slow down the reclaim and
3730	* prevent from pre mature OOM
3731	*/
3732	if (!did_some_progress) {
3733	unsigned long write_pending;
3734
3735	write_pending = zone_page_state_snapshot(zone,
3736	NR_ZONE_WRITE_PENDING);
3737
3738	if (2 * write_pending > reclaimable) {
3739	congestion_wait(BLK_RW_ASYNC, HZ/10);
3740	return true;
3741	}
3742	}
3743
3744	/*
3745	* Memory allocation/reclaim might be called from a WQ
3746	* context and the current implementation of the WQ
3747	* concurrency control doesn't recognize that
3748	* a particular WQ is congested if the worker thread is
3749	* looping without ever sleeping. Therefore we have to
3750	* do a short sleep here rather than calling
3751	* cond_resched().
3752	*/
3753	if (current->flags & PF_WQ_WORKER)
3754	schedule_timeout_uninterruptible(1);
3755	else
3756	cond_resched();
3757
3758	return true;
3759	}
3760	}
3761
3762	return false;
3763	}
3764
3765	static inline struct page *
3766	__alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
3767	struct alloc_context *ac)
3768	{
3769	bool can_direct_reclaim = gfp_mask & __GFP_DIRECT_RECLAIM;
3770	struct page *page = NULL;
3771	unsigned int alloc_flags;
3772	unsigned long did_some_progress;
3773	enum compact_priority compact_priority;
3774	enum compact_result compact_result;
3775	int compaction_retries;
3776	int no_progress_loops;
3777	unsigned int cpuset_mems_cookie;
3778
3779	/*
3780	* In the slowpath, we sanity check order to avoid ever trying to
3781	* reclaim >= MAX_ORDER areas which will never succeed. Callers may
3782	* be using allocators in order of preference for an area that is
3783	* too large.
3784	*/
3785	if (order >= MAX_ORDER) {
3786	WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN));
3787	return NULL;
3788	}
3789
3790	/*
3791	* We also sanity check to catch abuse of atomic reserves being used by
3792	* callers that are not in atomic context.
3793	*/
3794	if (WARN_ON_ONCE((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) ==
3795	(__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)))
3796	gfp_mask &= ~__GFP_ATOMIC;
3797
3798	retry_cpuset:
3799	compaction_retries = 0;
3800	no_progress_loops = 0;
3801	compact_priority = DEF_COMPACT_PRIORITY;
3802	cpuset_mems_cookie = read_mems_allowed_begin();
3803	/*
3804	* We need to recalculate the starting point for the zonelist iterator
3805	* because we might have used different nodemask in the fast path, or
3806	* there was a cpuset modification and we are retrying - otherwise we
3807	* could end up iterating over non-eligible zones endlessly.
3808	*/
3809	ac->preferred_zoneref = first_zones_zonelist(ac->zonelist,
3810	ac->high_zoneidx, ac->nodemask);
3811	if (!ac->preferred_zoneref->zone)
3812	goto nopage;
3813
3814
3815	/*
3816	* The fast path uses conservative alloc_flags to succeed only until
3817	* kswapd needs to be woken up, and to avoid the cost of setting up
3818	* alloc_flags precisely. So we do that now.
3819	*/
3820	alloc_flags = gfp_to_alloc_flags(gfp_mask);
3821
3822	if (gfp_mask & __GFP_KSWAPD_RECLAIM)
3823	wake_all_kswapds(order, ac);
3824
3825	/*
3826	* The adjusted alloc_flags might result in immediate success, so try
3827	* that first
3828	*/
3829	page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac);
3830	if (page)
3831	goto got_pg;
3832
3833	/*
3834	* For costly allocations, try direct compaction first, as it's likely
3835	* that we have enough base pages and don't need to reclaim. Don't try
3836	* that for allocations that are allowed to ignore watermarks, as the
3837	* ALLOC_NO_WATERMARKS attempt didn't yet happen.
3838	*/
3839	if (can_direct_reclaim && order > PAGE_ALLOC_COSTLY_ORDER &&
3840	!gfp_pfmemalloc_allowed(gfp_mask)) {
3841	page = __alloc_pages_direct_compact(gfp_mask, order,
3842	alloc_flags, ac,
3843	INIT_COMPACT_PRIORITY,
3844	&compact_result);
3845	if (page)
3846	goto got_pg;
3847
3848	/*
3849	* Checks for costly allocations with __GFP_NORETRY, which
3850	* includes THP page fault allocations
3851	*/
3852	if (gfp_mask & __GFP_NORETRY) {
3853	/*
3854	* If compaction is deferred for high-order allocations,
3855	* it is because sync compaction recently failed. If
3856	* this is the case and the caller requested a THP
3857	* allocation, we do not want to heavily disrupt the
3858	* system, so we fail the allocation instead of entering
3859	* direct reclaim.
3860	*/
3861	if (compact_result == COMPACT_DEFERRED)
3862	goto nopage;
3863
3864	/*
3865	* Looks like reclaim/compaction is worth trying, but
3866	* sync compaction could be very expensive, so keep
3867	* using async compaction.
3868	*/
3869	compact_priority = INIT_COMPACT_PRIORITY;
3870	}
3871	}
3872
3873	retry:
3874	/* Ensure kswapd doesn't accidentally go to sleep as long as we loop */
3875	if (gfp_mask & __GFP_KSWAPD_RECLAIM)
3876	wake_all_kswapds(order, ac);
3877
3878	if (gfp_pfmemalloc_allowed(gfp_mask))
3879	alloc_flags = ALLOC_NO_WATERMARKS;
3880
3881	/*
3882	* Reset the zonelist iterators if memory policies can be ignored.
3883	* These allocations are high priority and system rather than user
3884	* orientated.
3885	*/
3886	if (!(alloc_flags & ALLOC_CPUSET) || (alloc_flags & ALLOC_NO_WATERMARKS)) {
3887	ac->preferred_zoneref = first_zones_zonelist(ac->zonelist,
3888	ac->high_zoneidx, ac->nodemask);
3889	}
3890
3891	/* Attempt with potentially adjusted zonelist and alloc_flags */
3892	page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac);
3893	if (page)
3894	goto got_pg;
3895
3896	/* Caller is not willing to reclaim, we can't balance anything */
3897	if (!can_direct_reclaim) {
3898	/*
3899	* All existing users of the __GFP_NOFAIL are blockable, so warn
3900	* of any new users that actually allow this type of allocation
3901	* to fail.
3902	*/
3903	WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL);
3904	goto nopage;
3905	}
3906
3907	/* Avoid recursion of direct reclaim */
3908	if (current->flags & PF_MEMALLOC) {
3909	/*
3910	* __GFP_NOFAIL request from this context is rather bizarre
3911	* because we cannot reclaim anything and only can loop waiting
3912	* for somebody to do a work for us.
3913	*/
3914	if (WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL)) {
3915	cond_resched();
3916	goto retry;
3917	}
3918	goto nopage;
3919	}
3920
3921	/* Avoid allocations with no watermarks from looping endlessly */
3922	if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL))
3923	goto nopage;
3924
3925
3926	/* Try direct reclaim and then allocating */
3927	page = __alloc_pages_direct_reclaim(gfp_mask, order, alloc_flags, ac,
3928	&did_some_progress);
3929	if (page)
3930	goto got_pg;
3931
3932	/* Try direct compaction and then allocating */
3933	page = __alloc_pages_direct_compact(gfp_mask, order, alloc_flags, ac,
3934	compact_priority, &compact_result);
3935	if (page)
3936	goto got_pg;
3937
3938	/* Do not loop if specifically requested */
3939	if (gfp_mask & __GFP_NORETRY)
3940	goto nopage;
3941
3942	/*
3943	* Do not retry costly high order allocations unless they are
3944	* __GFP_REPEAT
3945	*/
3946	if (order > PAGE_ALLOC_COSTLY_ORDER && !(gfp_mask & __GFP_REPEAT))
3947	goto nopage;
3948
3949	if (should_reclaim_retry(gfp_mask, order, ac, alloc_flags,
3950	did_some_progress > 0, &no_progress_loops))
3951	goto retry;
3952
3953	/*
3954	* It doesn't make any sense to retry for the compaction if the order-0
3955	* reclaim is not able to make any progress because the current
3956	* implementation of the compaction depends on the sufficient amount
3957	* of free memory (see __compaction_suitable)
3958	*/
3959	if (did_some_progress > 0 &&
3960	should_compact_retry(ac, order, alloc_flags,
3961	compact_result, &compact_priority,
3962	&compaction_retries))
3963	goto retry;
3964
3965	/*
3966	* It's possible we raced with cpuset update so the OOM would be
3967	* premature (see below the nopage: label for full explanation).
3968	*/
3969	if (read_mems_allowed_retry(cpuset_mems_cookie))
3970	goto retry_cpuset;
3971
3972	/* Reclaim has failed us, start killing things */
3973	page = __alloc_pages_may_oom(gfp_mask, order, ac, &did_some_progress);
3974	if (page)
3975	goto got_pg;
3976
3977	/* Retry as long as the OOM killer is making progress */
3978	if (did_some_progress) {
3979	no_progress_loops = 0;
3980	goto retry;
3981	}
3982
3983	nopage:
3984	/*
3985	* When updating a task's mems_allowed or mempolicy nodemask, it is
3986	* possible to race with parallel threads in such a way that our
3987	* allocation can fail while the mask is being updated. If we are about
3988	* to fail, check if the cpuset changed during allocation and if so,
3989	* retry.
3990	*/
3991	if (read_mems_allowed_retry(cpuset_mems_cookie))
3992	goto retry_cpuset;
3993
3994	warn_alloc(gfp_mask,
3995	"page allocation failure: order:%u", order);
3996	got_pg:
3997	return page;
3998	}
3999
4000	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
4001	static inline void should_wakeup_kswap(gfp_t gfp_mask, int order,
4002	struct alloc_context *ac)
4003	{
4004	unsigned long free_pages, free_cma = 0;
4005	struct zoneref *z = ac->preferred_zoneref;
4006	struct zone *zone;
4007
4008	if (!(gfp_mask & __GFP_RECLAIM)) /* not allowed */
4009	return;
4010
4011	for_next_zone_zonelist_nodemask(zone, z, ac->zonelist, ac->high_zoneidx,
4012	ac->nodemask) {
4013	free_pages = zone_page_state(zone, NR_FREE_PAGES);
4014	#ifdef CONFIG_AMLOGIC_CMA
4015	if (can_use_cma(gfp_mask))
4016	free_cma = zone_page_state(zone, NR_FREE_CMA_PAGES);
4017	#endif /* CONFIG_AMLOGIC_CMA */
4018	free_pages -= free_cma;
4019	/*
4020	* wake up kswapd before get pages from buddy, this help to
4021	* fast reclaim process and can avoid memory become too low
4022	* some times
4023	*/
4024	if (free_pages <= high_wmark_pages(zone))
4025	wakeup_kswapd(zone, order, ac->high_zoneidx);
4026	}
4027	}
4028	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
4029
4030	/*
4031	* This is the 'heart' of the zoned buddy allocator.
4032	*/
4033	struct page *
4034	__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
4035	struct zonelist *zonelist, nodemask_t *nodemask)
4036	{
4037	struct page *page;
4038	unsigned int alloc_flags = ALLOC_WMARK_LOW;
4039	gfp_t alloc_mask = gfp_mask; /* The gfp_t that was actually used for allocation */
4040	struct alloc_context ac = {
4041	.high_zoneidx = gfp_zone(gfp_mask),
4042	.zonelist = zonelist,
4043	.nodemask = nodemask,
4044	.migratetype = gfpflags_to_migratetype(gfp_mask),
4045	};
4046
4047	if (cpusets_enabled()) {
4048	alloc_mask |= __GFP_HARDWALL;
4049	alloc_flags |= ALLOC_CPUSET;
4050	if (!ac.nodemask)
4051	ac.nodemask = &cpuset_current_mems_allowed;
4052	}
4053
4054	gfp_mask &= gfp_allowed_mask;
4055
4056	lockdep_trace_alloc(gfp_mask);
4057
4058	might_sleep_if(gfp_mask & __GFP_DIRECT_RECLAIM);
4059
4060	if (should_fail_alloc_page(gfp_mask, order))
4061	return NULL;
4062
4063	/*
4064	* Check the zones suitable for the gfp_mask contain at least one
4065	* valid zone. It's possible to have an empty zonelist as a result
4066	* of __GFP_THISNODE and a memoryless node
4067	*/
4068	if (unlikely(!zonelist->_zonerefs->zone))
4069	return NULL;
4070
4071	if (IS_ENABLED(CONFIG_CMA) && ac.migratetype == MIGRATE_MOVABLE)
4072	alloc_flags |= ALLOC_CMA;
4073
4074	/* Dirty zone balancing only done in the fast path */
4075	ac.spread_dirty_pages = (gfp_mask & __GFP_WRITE);
4076
4077	/*
4078	* The preferred zone is used for statistics but crucially it is
4079	* also used as the starting point for the zonelist iterator. It
4080	* may get reset for allocations that ignore memory policies.
4081	*/
4082	ac.preferred_zoneref = first_zones_zonelist(ac.zonelist,
4083	ac.high_zoneidx, ac.nodemask);
4084	if (!ac.preferred_zoneref->zone) {
4085	page = NULL;
4086	/*
4087	* This might be due to race with cpuset_current_mems_allowed
4088	* update, so make sure we retry with original nodemask in the
4089	* slow path.
4090	*/
4091	goto no_zone;
4092	}
4093	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
4094	should_wakeup_kswap(gfp_mask, order, &ac);
4095	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
4096
4097	/* First allocation attempt */
4098	page = get_page_from_freelist(alloc_mask, order, alloc_flags, &ac);
4099	if (likely(page))
4100	goto out;
4101
4102	no_zone:
4103	/*
4104	* Runtime PM, block IO and its error handling path can deadlock
4105	* because I/O on the device might not complete.
4106	*/
4107	alloc_mask = memalloc_noio_flags(gfp_mask);
4108	ac.spread_dirty_pages = false;
4109
4110	/*
4111	* Restore the original nodemask if it was potentially replaced with
4112	* &cpuset_current_mems_allowed to optimize the fast-path attempt.
4113	*/
4114	if (unlikely(ac.nodemask != nodemask))
4115	ac.nodemask = nodemask;
4116
4117	page = __alloc_pages_slowpath(alloc_mask, order, &ac);
4118
4119	out:
4120	if (memcg_kmem_enabled() && (gfp_mask & __GFP_ACCOUNT) && page &&
4121	unlikely(memcg_kmem_charge(page, gfp_mask, order) != 0)) {
4122	__free_pages(page, order);
4123	page = NULL;
4124	}
4125
4126	if (kmemcheck_enabled && page)
4127	kmemcheck_pagealloc_alloc(page, order, gfp_mask);
4128
4129	trace_mm_page_alloc(page, order, alloc_mask, ac.migratetype);
4130	#ifdef CONFIG_AMLOGIC_PAGE_TRACE
4131	set_page_trace(page, order, gfp_mask, NULL);
4132	#endif /* CONFIG_AMLOGIC_PAGE_TRACE */
4133
4134	return page;
4135	}
4136	EXPORT_SYMBOL(__alloc_pages_nodemask);
4137
4138	/*
4139	* Common helper functions.
4140	*/
4141	unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order)
4142	{
4143	struct page *page;
4144
4145	/*
4146	* __get_free_pages() returns a 32-bit address, which cannot represent
4147	* a highmem page
4148	*/
4149	VM_BUG_ON((gfp_mask & __GFP_HIGHMEM) != 0);
4150
4151	page = alloc_pages(gfp_mask, order);
4152	if (!page)
4153	return 0;
4154	return (unsigned long) page_address(page);
4155	}
4156	EXPORT_SYMBOL(__get_free_pages);
4157
4158	unsigned long get_zeroed_page(gfp_t gfp_mask)
4159	{
4160	return __get_free_pages(gfp_mask | __GFP_ZERO, 0);
4161	}
4162	EXPORT_SYMBOL(get_zeroed_page);
4163
4164	void __free_pages(struct page *page, unsigned int order)
4165	{
4166	if (put_page_testzero(page)) {
4167	if (order == 0)
4168	free_hot_cold_page(page, false);
4169	else
4170	__free_pages_ok(page, order);
4171	}
4172	}
4173
4174	EXPORT_SYMBOL(__free_pages);
4175
4176	void free_pages(unsigned long addr, unsigned int order)
4177	{
4178	if (addr != 0) {
4179	VM_BUG_ON(!virt_addr_valid((void *)addr));
4180	__free_pages(virt_to_page((void *)addr), order);
4181	}
4182	}
4183
4184	EXPORT_SYMBOL(free_pages);
4185
4186	/*
4187	* Page Fragment:
4188	* An arbitrary-length arbitrary-offset area of memory which resides
4189	* within a 0 or higher order page. Multiple fragments within that page
4190	* are individually refcounted, in the page's reference counter.
4191	*
4192	* The page_frag functions below provide a simple allocation framework for
4193	* page fragments. This is used by the network stack and network device
4194	* drivers to provide a backing region of memory for use as either an
4195	* sk_buff->head, or to be used in the "frags" portion of skb_shared_info.
4196	*/
4197	static struct page *__page_frag_refill(struct page_frag_cache *nc,
4198	gfp_t gfp_mask)
4199	{
4200	struct page *page = NULL;
4201	gfp_t gfp = gfp_mask;
4202
4203	#if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
4204	gfp_mask |= __GFP_COMP | __GFP_NOWARN | __GFP_NORETRY |
4205	__GFP_NOMEMALLOC;
4206	page = alloc_pages_node(NUMA_NO_NODE, gfp_mask,
4207	PAGE_FRAG_CACHE_MAX_ORDER);
4208	nc->size = page ? PAGE_FRAG_CACHE_MAX_SIZE : PAGE_SIZE;
4209	#endif
4210	if (unlikely(!page))
4211	page = alloc_pages_node(NUMA_NO_NODE, gfp, 0);
4212
4213	nc->va = page ? page_address(page) : NULL;
4214
4215	return page;
4216	}
4217
4218	void *__alloc_page_frag(struct page_frag_cache *nc,
4219	unsigned int fragsz, gfp_t gfp_mask)
4220	{
4221	unsigned int size = PAGE_SIZE;
4222	struct page *page;
4223	int offset;
4224
4225	if (unlikely(!nc->va)) {
4226	refill:
4227	page = __page_frag_refill(nc, gfp_mask);
4228	if (!page)
4229	return NULL;
4230
4231	#if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
4232	/* if size can vary use size else just use PAGE_SIZE */
4233	size = nc->size;
4234	#endif
4235	/* Even if we own the page, we do not use atomic_set().
4236	* This would break get_page_unless_zero() users.
4237	*/
4238	page_ref_add(page, size);
4239
4240	/* reset page count bias and offset to start of new frag */
4241	nc->pfmemalloc = page_is_pfmemalloc(page);
4242	nc->pagecnt_bias = size + 1;
4243	nc->offset = size;
4244	}
4245
4246	offset = nc->offset - fragsz;
4247	if (unlikely(offset < 0)) {
4248	page = virt_to_page(nc->va);
4249
4250	if (!page_ref_sub_and_test(page, nc->pagecnt_bias))
4251	goto refill;
4252
4253	#if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
4254	/* if size can vary use size else just use PAGE_SIZE */
4255	size = nc->size;
4256	#endif
4257	/* OK, page count is 0, we can safely set it */
4258	set_page_count(page, size + 1);
4259
4260	/* reset page count bias and offset to start of new frag */
4261	nc->pagecnt_bias = size + 1;
4262	offset = size - fragsz;
4263	}
4264
4265	nc->pagecnt_bias--;
4266	nc->offset = offset;
4267
4268	return nc->va + offset;
4269	}
4270	EXPORT_SYMBOL(__alloc_page_frag);
4271
4272	/*
4273	* Frees a page fragment allocated out of either a compound or order 0 page.
4274	*/
4275	void __free_page_frag(void *addr)
4276	{
4277	struct page *page = virt_to_head_page(addr);
4278
4279	if (unlikely(put_page_testzero(page)))
4280	__free_pages_ok(page, compound_order(page));
4281	}
4282	EXPORT_SYMBOL(__free_page_frag);
4283
4284	static void *make_alloc_exact(unsigned long addr, unsigned int order,
4285	size_t size)
4286	{
4287	if (addr) {
4288	unsigned long alloc_end = addr + (PAGE_SIZE << order);
4289	unsigned long used = addr + PAGE_ALIGN(size);
4290
4291	split_page(virt_to_page((void *)addr), order);
4292	while (used < alloc_end) {
4293	free_page(used);
4294	used += PAGE_SIZE;
4295	}
4296	}
4297	return (void *)addr;
4298	}
4299
4300	/**
4301	* alloc_pages_exact - allocate an exact number physically-contiguous pages.
4302	* @size: the number of bytes to allocate
4303	* @gfp_mask: GFP flags for the allocation
4304	*
4305	* This function is similar to alloc_pages(), except that it allocates the
4306	* minimum number of pages to satisfy the request. alloc_pages() can only
4307	* allocate memory in power-of-two pages.
4308	*
4309	* This function is also limited by MAX_ORDER.
4310	*
4311	* Memory allocated by this function must be released by free_pages_exact().
4312	*/
4313	void *alloc_pages_exact(size_t size, gfp_t gfp_mask)
4314	{
4315	unsigned int order = get_order(size);
4316	unsigned long addr;
4317
4318	addr = __get_free_pages(gfp_mask, order);
4319	return make_alloc_exact(addr, order, size);
4320	}
4321	EXPORT_SYMBOL(alloc_pages_exact);
4322
4323	/**
4324	* alloc_pages_exact_nid - allocate an exact number of physically-contiguous
4325	* pages on a node.
4326	* @nid: the preferred node ID where memory should be allocated
4327	* @size: the number of bytes to allocate
4328	* @gfp_mask: GFP flags for the allocation
4329	*
4330	* Like alloc_pages_exact(), but try to allocate on node nid first before falling
4331	* back.
4332	*/
4333	void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask)
4334	{
4335	unsigned int order = get_order(size);
4336	struct page *p = alloc_pages_node(nid, gfp_mask, order);
4337	if (!p)
4338	return NULL;
4339	return make_alloc_exact((unsigned long)page_address(p), order, size);
4340	}
4341
4342	/**
4343	* free_pages_exact - release memory allocated via alloc_pages_exact()
4344	* @virt: the value returned by alloc_pages_exact.
4345	* @size: size of allocation, same value as passed to alloc_pages_exact().
4346	*
4347	* Release the memory allocated by a previous call to alloc_pages_exact.
4348	*/
4349	void free_pages_exact(void *virt, size_t size)
4350	{
4351	unsigned long addr = (unsigned long)virt;
4352	unsigned long end = addr + PAGE_ALIGN(size);
4353
4354	while (addr < end) {
4355	free_page(addr);
4356	addr += PAGE_SIZE;
4357	}
4358	}
4359	EXPORT_SYMBOL(free_pages_exact);
4360
4361	/**
4362	* nr_free_zone_pages - count number of pages beyond high watermark
4363	* @offset: The zone index of the highest zone
4364	*
4365	* nr_free_zone_pages() counts the number of counts pages which are beyond the
4366	* high watermark within all zones at or below a given zone index. For each
4367	* zone, the number of pages is calculated as:
4368	* managed_pages - high_pages
4369	*/
4370	static unsigned long nr_free_zone_pages(int offset)
4371	{
4372	struct zoneref *z;
4373	struct zone *zone;
4374
4375	/* Just pick one node, since fallback list is circular */
4376	unsigned long sum = 0;
4377
4378	struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL);
4379
4380	for_each_zone_zonelist(zone, z, zonelist, offset) {
4381	unsigned long size = zone->managed_pages;
4382	unsigned long high = high_wmark_pages(zone);
4383	if (size > high)
4384	sum += size - high;
4385	}
4386
4387	return sum;
4388	}
4389
4390	/**
4391	* nr_free_buffer_pages - count number of pages beyond high watermark
4392	*
4393	* nr_free_buffer_pages() counts the number of pages which are beyond the high
4394	* watermark within ZONE_DMA and ZONE_NORMAL.
4395	*/
4396	unsigned long nr_free_buffer_pages(void)
4397	{
4398	return nr_free_zone_pages(gfp_zone(GFP_USER));
4399	}
4400	EXPORT_SYMBOL_GPL(nr_free_buffer_pages);
4401
4402	/**
4403	* nr_free_pagecache_pages - count number of pages beyond high watermark
4404	*
4405	* nr_free_pagecache_pages() counts the number of pages which are beyond the
4406	* high watermark within all zones.
4407	*/
4408	unsigned long nr_free_pagecache_pages(void)
4409	{
4410	return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
4411	}
4412
4413	static inline void show_node(struct zone *zone)
4414	{
4415	if (IS_ENABLED(CONFIG_NUMA))
4416	printk("Node %d ", zone_to_nid(zone));
4417	}
4418
4419	long si_mem_available(void)
4420	{
4421	long available;
4422	unsigned long pagecache;
4423	unsigned long wmark_low = 0;
4424	unsigned long pages[NR_LRU_LISTS];
4425	struct zone *zone;
4426	int lru;
4427
4428	for (lru = LRU_BASE; lru < NR_LRU_LISTS; lru++)
4429	pages[lru] = global_node_page_state(NR_LRU_BASE + lru);
4430
4431	for_each_zone(zone)
4432	wmark_low += zone->watermark[WMARK_LOW];
4433
4434	/*
4435	* Estimate the amount of memory available for userspace allocations,
4436	* without causing swapping.
4437	*/
4438	available = global_page_state(NR_FREE_PAGES) - totalreserve_pages;
4439
4440	/*
4441	* Not all the page cache can be freed, otherwise the system will
4442	* start swapping. Assume at least half of the page cache, or the
4443	* low watermark worth of cache, needs to stay.
4444	*/
4445	pagecache = pages[LRU_ACTIVE_FILE] + pages[LRU_INACTIVE_FILE];
4446	pagecache -= min(pagecache / 2, wmark_low);
4447	available += pagecache;
4448
4449	/*
4450	* Part of the reclaimable slab consists of items that are in use,
4451	* and cannot be freed. Cap this estimate at the low watermark.
4452	*/
4453	available += global_page_state(NR_SLAB_RECLAIMABLE) -
4454	min(global_page_state(NR_SLAB_RECLAIMABLE) / 2, wmark_low);
4455
4456	if (available < 0)
4457	available = 0;
4458	return available;
4459	}
4460	EXPORT_SYMBOL_GPL(si_mem_available);
4461
4462	void si_meminfo(struct sysinfo *val)
4463	{
4464	val->totalram = totalram_pages;
4465	val->sharedram = global_node_page_state(NR_SHMEM);
4466	val->freeram = global_page_state(NR_FREE_PAGES);
4467	val->bufferram = nr_blockdev_pages();
4468	val->totalhigh = totalhigh_pages;
4469	val->freehigh = nr_free_highpages();
4470	val->mem_unit = PAGE_SIZE;
4471	}
4472
4473	EXPORT_SYMBOL(si_meminfo);
4474
4475	#ifdef CONFIG_NUMA
4476	void si_meminfo_node(struct sysinfo *val, int nid)
4477	{
4478	int zone_type; /* needs to be signed */
4479	unsigned long managed_pages = 0;
4480	unsigned long managed_highpages = 0;
4481	unsigned long free_highpages = 0;
4482	pg_data_t *pgdat = NODE_DATA(nid);
4483
4484	for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++)
4485	managed_pages += pgdat->node_zones[zone_type].managed_pages;
4486	val->totalram = managed_pages;
4487	val->sharedram = node_page_state(pgdat, NR_SHMEM);
4488	val->freeram = sum_zone_node_page_state(nid, NR_FREE_PAGES);
4489	#ifdef CONFIG_HIGHMEM
4490	for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
4491	struct zone *zone = &pgdat->node_zones[zone_type];
4492
4493	if (is_highmem(zone)) {
4494	managed_highpages += zone->managed_pages;
4495	free_highpages += zone_page_state(zone, NR_FREE_PAGES);
4496	}
4497	}
4498	val->totalhigh = managed_highpages;
4499	val->freehigh = free_highpages;
4500	#else
4501	val->totalhigh = managed_highpages;
4502	val->freehigh = free_highpages;
4503	#endif
4504	val->mem_unit = PAGE_SIZE;
4505	}
4506	#endif
4507
4508	/*
4509	* Determine whether the node should be displayed or not, depending on whether
4510	* SHOW_MEM_FILTER_NODES was passed to show_free_areas().
4511	*/
4512	bool skip_free_areas_node(unsigned int flags, int nid)
4513	{
4514	bool ret = false;
4515	unsigned int cpuset_mems_cookie;
4516
4517	if (!(flags & SHOW_MEM_FILTER_NODES))
4518	goto out;
4519
4520	do {
4521	cpuset_mems_cookie = read_mems_allowed_begin();
4522	ret = !node_isset(nid, cpuset_current_mems_allowed);
4523	} while (read_mems_allowed_retry(cpuset_mems_cookie));
4524	out:
4525	return ret;
4526	}
4527
4528	#define K(x) ((x) << (PAGE_SHIFT-10))
4529
4530	static void show_migration_types(unsigned char type)
4531	{
4532	static const char types[MIGRATE_TYPES] = {
4533	[MIGRATE_UNMOVABLE] = 'U',
4534	[MIGRATE_MOVABLE] = 'M',
4535	[MIGRATE_RECLAIMABLE] = 'E',
4536	[MIGRATE_HIGHATOMIC] = 'H',
4537	#ifdef CONFIG_CMA
4538	[MIGRATE_CMA] = 'C',
4539	#endif
4540	#ifdef CONFIG_MEMORY_ISOLATION
4541	[MIGRATE_ISOLATE] = 'I',
4542	#endif
4543	};
4544	char tmp[MIGRATE_TYPES + 1];
4545	char *p = tmp;
4546	int i;
4547
4548	for (i = 0; i < MIGRATE_TYPES; i++) {
4549	if (type & (1 << i))
4550	*p++ = types[i];
4551	}
4552
4553	*p = '\0';
4554	printk(KERN_CONT "(%s) ", tmp);
4555	}
4556
4557	/*
4558	* Show free area list (used inside shift_scroll-lock stuff)
4559	* We also calculate the percentage fragmentation. We do this by counting the
4560	* memory on each free list with the exception of the first item on the list.
4561	*
4562	* Bits in @filter:
4563	* SHOW_MEM_FILTER_NODES: suppress nodes that are not allowed by current's
4564	* cpuset.
4565	*/
4566	void show_free_areas(unsigned int filter)
4567	{
4568	unsigned long free_pcp = 0;
4569	int cpu;
4570	struct zone *zone;
4571	pg_data_t *pgdat;
4572
4573	for_each_populated_zone(zone) {
4574	if (skip_free_areas_node(filter, zone_to_nid(zone)))
4575	continue;
4576
4577	for_each_online_cpu(cpu)
4578	free_pcp += per_cpu_ptr(zone->pageset, cpu)->pcp.count;
4579	}
4580
4581	printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
4582	" active_file:%lu inactive_file:%lu isolated_file:%lu\n"
4583	" unevictable:%lu dirty:%lu writeback:%lu unstable:%lu\n"
4584	" slab_reclaimable:%lu slab_unreclaimable:%lu\n"
4585	" mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n"
4586	#ifdef CONFIG_AMLOGIC_CMA
4587	" [cma] driver:%lu anon:%lu file:%lu isolate:%lu total:%lu\n"
4588	#endif /* CONFIG_AMLOGIC_CMA */
4589	" free:%lu free_pcp:%lu free_cma:%lu\n",
4590	global_node_page_state(NR_ACTIVE_ANON),
4591	global_node_page_state(NR_INACTIVE_ANON),
4592	global_node_page_state(NR_ISOLATED_ANON),
4593	global_node_page_state(NR_ACTIVE_FILE),
4594	global_node_page_state(NR_INACTIVE_FILE),
4595	global_node_page_state(NR_ISOLATED_FILE),
4596	global_node_page_state(NR_UNEVICTABLE),
4597	global_node_page_state(NR_FILE_DIRTY),
4598	global_node_page_state(NR_WRITEBACK),
4599	global_node_page_state(NR_UNSTABLE_NFS),
4600	global_page_state(NR_SLAB_RECLAIMABLE),
4601	global_page_state(NR_SLAB_UNRECLAIMABLE),
4602	global_node_page_state(NR_FILE_MAPPED),
4603	global_node_page_state(NR_SHMEM),
4604	global_page_state(NR_PAGETABLE),
4605	global_page_state(NR_BOUNCE),
4606	#ifdef CONFIG_AMLOGIC_CMA
4607	get_cma_allocated(),
4608	global_page_state(NR_INACTIVE_ANON_CMA) +
4609	global_page_state(NR_ACTIVE_ANON_CMA),
4610	global_page_state(NR_INACTIVE_FILE_CMA) +
4611	global_page_state(NR_ACTIVE_FILE_CMA),
4612	global_page_state(NR_CMA_ISOLATED),
4613	totalcma_pages,
4614	#endif /* CONFIG_AMLOGIC_CMA */
4615	global_page_state(NR_FREE_PAGES),
4616	free_pcp,
4617	global_page_state(NR_FREE_CMA_PAGES));
4618
4619	for_each_online_pgdat(pgdat) {
4620	printk("Node %d"
4621	" active_anon:%lukB"
4622	" inactive_anon:%lukB"
4623	" active_file:%lukB"
4624	" inactive_file:%lukB"
4625	" unevictable:%lukB"
4626	" isolated(anon):%lukB"
4627	" isolated(file):%lukB"
4628	" mapped:%lukB"
4629	" dirty:%lukB"
4630	" writeback:%lukB"
4631	" shmem:%lukB"
4632	#ifdef CONFIG_TRANSPARENT_HUGEPAGE
4633	" shmem_thp: %lukB"
4634	" shmem_pmdmapped: %lukB"
4635	" anon_thp: %lukB"
4636	#endif
4637	" writeback_tmp:%lukB"
4638	" unstable:%lukB"
4639	" pages_scanned:%lu"
4640	" all_unreclaimable? %s"
4641	"\n",
4642	pgdat->node_id,
4643	K(node_page_state(pgdat, NR_ACTIVE_ANON)),
4644	K(node_page_state(pgdat, NR_INACTIVE_ANON)),
4645	K(node_page_state(pgdat, NR_ACTIVE_FILE)),
4646	K(node_page_state(pgdat, NR_INACTIVE_FILE)),
4647	K(node_page_state(pgdat, NR_UNEVICTABLE)),
4648	K(node_page_state(pgdat, NR_ISOLATED_ANON)),
4649	K(node_page_state(pgdat, NR_ISOLATED_FILE)),
4650	K(node_page_state(pgdat, NR_FILE_MAPPED)),
4651	K(node_page_state(pgdat, NR_FILE_DIRTY)),
4652	K(node_page_state(pgdat, NR_WRITEBACK)),
4653	K(node_page_state(pgdat, NR_SHMEM)),
4654	#ifdef CONFIG_TRANSPARENT_HUGEPAGE
4655	K(node_page_state(pgdat, NR_SHMEM_THPS) * HPAGE_PMD_NR),
4656	K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED)
4657	* HPAGE_PMD_NR),
4658	K(node_page_state(pgdat, NR_ANON_THPS) * HPAGE_PMD_NR),
4659	#endif
4660	K(node_page_state(pgdat, NR_WRITEBACK_TEMP)),
4661	K(node_page_state(pgdat, NR_UNSTABLE_NFS)),
4662	node_page_state(pgdat, NR_PAGES_SCANNED),
4663	pgdat->kswapd_failures >= MAX_RECLAIM_RETRIES ?
4664	"yes" : "no");
4665	}
4666
4667	for_each_populated_zone(zone) {
4668	int i;
4669
4670	if (skip_free_areas_node(filter, zone_to_nid(zone)))
4671	continue;
4672
4673	free_pcp = 0;
4674	for_each_online_cpu(cpu)
4675	free_pcp += per_cpu_ptr(zone->pageset, cpu)->pcp.count;
4676
4677	show_node(zone);
4678	printk(KERN_CONT
4679	"%s"
4680	" free:%lukB"
4681	" min:%lukB"
4682	" low:%lukB"
4683	" high:%lukB"
4684	" active_anon:%lukB"
4685	" inactive_anon:%lukB"
4686	" active_file:%lukB"
4687	" inactive_file:%lukB"
4688	" unevictable:%lukB"
4689	" writepending:%lukB"
4690	" present:%lukB"
4691	" managed:%lukB"
4692	" mlocked:%lukB"
4693	" slab_reclaimable:%lukB"
4694	" slab_unreclaimable:%lukB"
4695	" kernel_stack:%lukB"
4696	" pagetables:%lukB"
4697	" bounce:%lukB"
4698	" free_pcp:%lukB"
4699	" local_pcp:%ukB"
4700	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
4701	" free_unmovable:%lukB"
4702	" free_movable:%lukB"
4703	" free_reclaimable:%lukB"
4704	" free_highatomic:%lukB"
4705	#ifdef CONFIG_MEMORY_ISOLATION
4706	" free_isolate:%lukB"
4707	#endif
4708	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
4709	" free_cma:%lukB"
4710	"\n",
4711	zone->name,
4712	K(zone_page_state(zone, NR_FREE_PAGES)),
4713	K(min_wmark_pages(zone)),
4714	K(low_wmark_pages(zone)),
4715	K(high_wmark_pages(zone)),
4716	K(zone_page_state(zone, NR_ZONE_ACTIVE_ANON)),
4717	K(zone_page_state(zone, NR_ZONE_INACTIVE_ANON)),
4718	K(zone_page_state(zone, NR_ZONE_ACTIVE_FILE)),
4719	K(zone_page_state(zone, NR_ZONE_INACTIVE_FILE)),
4720	K(zone_page_state(zone, NR_ZONE_UNEVICTABLE)),
4721	K(zone_page_state(zone, NR_ZONE_WRITE_PENDING)),
4722	K(zone->present_pages),
4723	K(zone->managed_pages),
4724	K(zone_page_state(zone, NR_MLOCK)),
4725	K(zone_page_state(zone, NR_SLAB_RECLAIMABLE)),
4726	K(zone_page_state(zone, NR_SLAB_UNRECLAIMABLE)),
4727	zone_page_state(zone, NR_KERNEL_STACK_KB),
4728	K(zone_page_state(zone, NR_PAGETABLE)),
4729	K(zone_page_state(zone, NR_BOUNCE)),
4730	K(free_pcp),
4731	K(this_cpu_read(zone->pageset->pcp.count)),
4732	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
4733	K(zone_page_state(zone, NR_FREE_UNMOVABLE)),
4734	K(zone_page_state(zone, NR_FREE_MOVABLE)),
4735	K(zone_page_state(zone, NR_FREE_RECLAIMABLE)),
4736	K(zone_page_state(zone, NR_FREE_HIGHATOMIC)),
4737	#ifdef CONFIG_MEMORY_ISOLATION
4738	K(zone_page_state(zone, NR_FREE_ISOLATE)),
4739	#endif
4740	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
4741	K(zone_page_state(zone, NR_FREE_CMA_PAGES)));
4742	printk("lowmem_reserve[]:");
4743	for (i = 0; i < MAX_NR_ZONES; i++)
4744	printk(KERN_CONT " %ld", zone->lowmem_reserve[i]);
4745	printk(KERN_CONT "\n");
4746	}
4747
4748	for_each_populated_zone(zone) {
4749	unsigned int order;
4750	unsigned long nr[MAX_ORDER], flags, total = 0;
4751	unsigned char types[MAX_ORDER];
4752
4753	if (skip_free_areas_node(filter, zone_to_nid(zone)))
4754	continue;
4755	show_node(zone);
4756	printk(KERN_CONT "%s: ", zone->name);
4757
4758	spin_lock_irqsave(&zone->lock, flags);
4759	for (order = 0; order < MAX_ORDER; order++) {
4760	struct free_area *area = &zone->free_area[order];
4761	int type;
4762
4763	nr[order] = area->nr_free;
4764	total += nr[order] << order;
4765
4766	types[order] = 0;
4767	for (type = 0; type < MIGRATE_TYPES; type++) {
4768	if (!list_empty(&area->free_list[type]))
4769	types[order] |= 1 << type;
4770	}
4771	}
4772	spin_unlock_irqrestore(&zone->lock, flags);
4773	for (order = 0; order < MAX_ORDER; order++) {
4774	printk(KERN_CONT "%lu*%lukB ",
4775	nr[order], K(1UL) << order);
4776	if (nr[order])
4777	show_migration_types(types[order]);
4778	}
4779	printk(KERN_CONT "= %lukB\n", K(total));
4780	}
4781
4782	hugetlb_show_meminfo();
4783
4784	printk("%ld total pagecache pages\n", global_node_page_state(NR_FILE_PAGES));
4785
4786	show_swap_cache_info();
4787	}
4788
4789	static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref)
4790	{
4791	zoneref->zone = zone;
4792	zoneref->zone_idx = zone_idx(zone);
4793	}
4794
4795	/*
4796	* Builds allocation fallback zone lists.
4797	*
4798	* Add all populated zones of a node to the zonelist.
4799	*/
4800	static int build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist,
4801	int nr_zones)
4802	{
4803	struct zone *zone;
4804	enum zone_type zone_type = MAX_NR_ZONES;
4805
4806	do {
4807	zone_type--;
4808	zone = pgdat->node_zones + zone_type;
4809	if (managed_zone(zone)) {
4810	zoneref_set_zone(zone,
4811	&zonelist->_zonerefs[nr_zones++]);
4812	check_highest_zone(zone_type);
4813	}
4814	} while (zone_type);
4815
4816	return nr_zones;
4817	}
4818
4819
4820	/*
4821	* zonelist_order:
4822	* 0 = automatic detection of better ordering.
4823	* 1 = order by ([node] distance, -zonetype)
4824	* 2 = order by (-zonetype, [node] distance)
4825	*
4826	* If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
4827	* the same zonelist. So only NUMA can configure this param.
4828	*/
4829	#define ZONELIST_ORDER_DEFAULT 0
4830	#define ZONELIST_ORDER_NODE 1
4831	#define ZONELIST_ORDER_ZONE 2
4832
4833	/* zonelist order in the kernel.
4834	* set_zonelist_order() will set this to NODE or ZONE.
4835	*/
4836	static int current_zonelist_order = ZONELIST_ORDER_DEFAULT;
4837	static char zonelist_order_name[3][8] = {"Default", "Node", "Zone"};
4838
4839
4840	#ifdef CONFIG_NUMA
4841	/* The value user specified ....changed by config */
4842	static int user_zonelist_order = ZONELIST_ORDER_DEFAULT;
4843	/* string for sysctl */
4844	#define NUMA_ZONELIST_ORDER_LEN 16
4845	char numa_zonelist_order[16] = "default";
4846
4847	/*
4848	* interface for configure zonelist ordering.
4849	* command line option "numa_zonelist_order"
4850	* = "[dD]efault - default, automatic configuration.
4851	* = "[nN]ode - order by node locality, then by zone within node
4852	* = "[zZ]one - order by zone, then by locality within zone
4853	*/
4854
4855	static int __parse_numa_zonelist_order(char *s)
4856	{
4857	if (*s == 'd' || *s == 'D') {
4858	user_zonelist_order = ZONELIST_ORDER_DEFAULT;
4859	} else if (*s == 'n' || *s == 'N') {
4860	user_zonelist_order = ZONELIST_ORDER_NODE;
4861	} else if (*s == 'z' || *s == 'Z') {
4862	user_zonelist_order = ZONELIST_ORDER_ZONE;
4863	} else {
4864	pr_warn("Ignoring invalid numa_zonelist_order value: %s\n", s);
4865	return -EINVAL;
4866	}
4867	return 0;
4868	}
4869
4870	static __init int setup_numa_zonelist_order(char *s)
4871	{
4872	int ret;
4873
4874	if (!s)
4875	return 0;
4876
4877	ret = __parse_numa_zonelist_order(s);
4878	if (ret == 0)
4879	strlcpy(numa_zonelist_order, s, NUMA_ZONELIST_ORDER_LEN);
4880
4881	return ret;
4882	}
4883	early_param("numa_zonelist_order", setup_numa_zonelist_order);
4884
4885	/*
4886	* sysctl handler for numa_zonelist_order
4887	*/
4888	int numa_zonelist_order_handler(struct ctl_table *table, int write,
4889	void __user *buffer, size_t *length,
4890	loff_t *ppos)
4891	{
4892	char saved_string[NUMA_ZONELIST_ORDER_LEN];
4893	int ret;
4894	static DEFINE_MUTEX(zl_order_mutex);
4895
4896	mutex_lock(&zl_order_mutex);
4897	if (write) {
4898	if (strlen((char *)table->data) >= NUMA_ZONELIST_ORDER_LEN) {
4899	ret = -EINVAL;
4900	goto out;
4901	}
4902	strcpy(saved_string, (char *)table->data);
4903	}
4904	ret = proc_dostring(table, write, buffer, length, ppos);
4905	if (ret)
4906	goto out;
4907	if (write) {
4908	int oldval = user_zonelist_order;
4909
4910	ret = __parse_numa_zonelist_order((char *)table->data);
4911	if (ret) {
4912	/*
4913	* bogus value. restore saved string
4914	*/
4915	strncpy((char *)table->data, saved_string,
4916	NUMA_ZONELIST_ORDER_LEN);
4917	user_zonelist_order = oldval;
4918	} else if (oldval != user_zonelist_order) {
4919	mutex_lock(&zonelists_mutex);
4920	build_all_zonelists(NULL, NULL);
4921	mutex_unlock(&zonelists_mutex);
4922	}
4923	}
4924	out:
4925	mutex_unlock(&zl_order_mutex);
4926	return ret;
4927	}
4928
4929
4930	#define MAX_NODE_LOAD (nr_online_nodes)
4931	static int node_load[MAX_NUMNODES];
4932
4933	/**
4934	* find_next_best_node - find the next node that should appear in a given node's fallback list
4935	* @node: node whose fallback list we're appending
4936	* @used_node_mask: nodemask_t of already used nodes
4937	*
4938	* We use a number of factors to determine which is the next node that should
4939	* appear on a given node's fallback list. The node should not have appeared
4940	* already in @node's fallback list, and it should be the next closest node
4941	* according to the distance array (which contains arbitrary distance values
4942	* from each node to each node in the system), and should also prefer nodes
4943	* with no CPUs, since presumably they'll have very little allocation pressure
4944	* on them otherwise.
4945	* It returns -1 if no node is found.
4946	*/
4947	static int find_next_best_node(int node, nodemask_t *used_node_mask)
4948	{
4949	int n, val;
4950	int min_val = INT_MAX;
4951	int best_node = NUMA_NO_NODE;
4952	const struct cpumask *tmp = cpumask_of_node(0);
4953
4954	/* Use the local node if we haven't already */
4955	if (!node_isset(node, *used_node_mask)) {
4956	node_set(node, *used_node_mask);
4957	return node;
4958	}
4959
4960	for_each_node_state(n, N_MEMORY) {
4961
4962	/* Don't want a node to appear more than once */
4963	if (node_isset(n, *used_node_mask))
4964	continue;
4965
4966	/* Use the distance array to find the distance */
4967	val = node_distance(node, n);
4968
4969	/* Penalize nodes under us ("prefer the next node") */
4970	val += (n < node);
4971
4972	/* Give preference to headless and unused nodes */
4973	tmp = cpumask_of_node(n);
4974	if (!cpumask_empty(tmp))
4975	val += PENALTY_FOR_NODE_WITH_CPUS;
4976
4977	/* Slight preference for less loaded node */
4978	val *= (MAX_NODE_LOAD*MAX_NUMNODES);
4979	val += node_load[n];
4980
4981	if (val < min_val) {
4982	min_val = val;
4983	best_node = n;
4984	}
4985	}
4986
4987	if (best_node >= 0)
4988	node_set(best_node, *used_node_mask);
4989
4990	return best_node;
4991	}
4992
4993
4994	/*
4995	* Build zonelists ordered by node and zones within node.
4996	* This results in maximum locality--normal zone overflows into local
4997	* DMA zone, if any--but risks exhausting DMA zone.
4998	*/
4999	static void build_zonelists_in_node_order(pg_data_t *pgdat, int node)
5000	{
5001	int j;
5002	struct zonelist *zonelist;
5003
5004	zonelist = &pgdat->node_zonelists[ZONELIST_FALLBACK];
5005	for (j = 0; zonelist->_zonerefs[j].zone != NULL; j++)
5006	;
5007	j = build_zonelists_node(NODE_DATA(node), zonelist, j);
5008	zonelist->_zonerefs[j].zone = NULL;
5009	zonelist->_zonerefs[j].zone_idx = 0;
5010	}
5011
5012	/*
5013	* Build gfp_thisnode zonelists
5014	*/
5015	static void build_thisnode_zonelists(pg_data_t *pgdat)
5016	{
5017	int j;
5018	struct zonelist *zonelist;
5019
5020	zonelist = &pgdat->node_zonelists[ZONELIST_NOFALLBACK];
5021	j = build_zonelists_node(pgdat, zonelist, 0);
5022	zonelist->_zonerefs[j].zone = NULL;
5023	zonelist->_zonerefs[j].zone_idx = 0;
5024	}
5025
5026	/*
5027	* Build zonelists ordered by zone and nodes within zones.
5028	* This results in conserving DMA zone[s] until all Normal memory is
5029	* exhausted, but results in overflowing to remote node while memory
5030	* may still exist in local DMA zone.
5031	*/
5032	static int node_order[MAX_NUMNODES];
5033
5034	static void build_zonelists_in_zone_order(pg_data_t *pgdat, int nr_nodes)
5035	{
5036	int pos, j, node;
5037	int zone_type; /* needs to be signed */
5038	struct zone *z;
5039	struct zonelist *zonelist;
5040
5041	zonelist = &pgdat->node_zonelists[ZONELIST_FALLBACK];
5042	pos = 0;
5043	for (zone_type = MAX_NR_ZONES - 1; zone_type >= 0; zone_type--) {
5044	for (j = 0; j < nr_nodes; j++) {
5045	node = node_order[j];
5046	z = &NODE_DATA(node)->node_zones[zone_type];
5047	if (managed_zone(z)) {
5048	zoneref_set_zone(z,
5049	&zonelist->_zonerefs[pos++]);
5050	check_highest_zone(zone_type);
5051	}
5052	}
5053	}
5054	zonelist->_zonerefs[pos].zone = NULL;
5055	zonelist->_zonerefs[pos].zone_idx = 0;
5056	}
5057
5058	#if defined(CONFIG_64BIT)
5059	/*
5060	* Devices that require DMA32/DMA are relatively rare and do not justify a
5061	* penalty to every machine in case the specialised case applies. Default
5062	* to Node-ordering on 64-bit NUMA machines
5063	*/
5064	static int default_zonelist_order(void)
5065	{
5066	return ZONELIST_ORDER_NODE;
5067	}
5068	#else
5069	/*
5070	* On 32-bit, the Normal zone needs to be preserved for allocations accessible
5071	* by the kernel. If processes running on node 0 deplete the low memory zone
5072	* then reclaim will occur more frequency increasing stalls and potentially
5073	* be easier to OOM if a large percentage of the zone is under writeback or
5074	* dirty. The problem is significantly worse if CONFIG_HIGHPTE is not set.
5075	* Hence, default to zone ordering on 32-bit.
5076	*/
5077	static int default_zonelist_order(void)
5078	{
5079	return ZONELIST_ORDER_ZONE;
5080	}
5081	#endif /* CONFIG_64BIT */
5082
5083	static void set_zonelist_order(void)
5084	{
5085	if (user_zonelist_order == ZONELIST_ORDER_DEFAULT)
5086	current_zonelist_order = default_zonelist_order();
5087	else
5088	current_zonelist_order = user_zonelist_order;
5089	}
5090
5091	static void build_zonelists(pg_data_t *pgdat)
5092	{
5093	int i, node, load;
5094	nodemask_t used_mask;
5095	int local_node, prev_node;
5096	struct zonelist *zonelist;
5097	unsigned int order = current_zonelist_order;
5098
5099	/* initialize zonelists */
5100	for (i = 0; i < MAX_ZONELISTS; i++) {
5101	zonelist = pgdat->node_zonelists + i;
5102	zonelist->_zonerefs[0].zone = NULL;
5103	zonelist->_zonerefs[0].zone_idx = 0;
5104	}
5105
5106	/* NUMA-aware ordering of nodes */
5107	local_node = pgdat->node_id;
5108	load = nr_online_nodes;
5109	prev_node = local_node;
5110	nodes_clear(used_mask);
5111
5112	memset(node_order, 0, sizeof(node_order));
5113	i = 0;
5114
5115	while ((node = find_next_best_node(local_node, &used_mask)) >= 0) {
5116	/*
5117	* We don't want to pressure a particular node.
5118	* So adding penalty to the first node in same
5119	* distance group to make it round-robin.
5120	*/
5121	if (node_distance(local_node, node) !=
5122	node_distance(local_node, prev_node))
5123	node_load[node] = load;
5124
5125	prev_node = node;
5126	load--;
5127	if (order == ZONELIST_ORDER_NODE)
5128	build_zonelists_in_node_order(pgdat, node);
5129	else
5130	node_order[i++] = node; /* remember order */
5131	}
5132
5133	if (order == ZONELIST_ORDER_ZONE) {
5134	/* calculate node order -- i.e., DMA last! */
5135	build_zonelists_in_zone_order(pgdat, i);
5136	}
5137
5138	build_thisnode_zonelists(pgdat);
5139	}
5140
5141	#ifdef CONFIG_HAVE_MEMORYLESS_NODES
5142	/*
5143	* Return node id of node used for "local" allocations.
5144	* I.e., first node id of first zone in arg node's generic zonelist.
5145	* Used for initializing percpu 'numa_mem', which is used primarily
5146	* for kernel allocations, so use GFP_KERNEL flags to locate zonelist.
5147	*/
5148	int local_memory_node(int node)
5149	{
5150	struct zoneref *z;
5151
5152	z = first_zones_zonelist(node_zonelist(node, GFP_KERNEL),
5153	gfp_zone(GFP_KERNEL),
5154	NULL);
5155	return z->zone->node;
5156	}
5157	#endif
5158
5159	static void setup_min_unmapped_ratio(void);
5160	static void setup_min_slab_ratio(void);
5161	#else /* CONFIG_NUMA */
5162
5163	static void set_zonelist_order(void)
5164	{
5165	current_zonelist_order = ZONELIST_ORDER_ZONE;
5166	}
5167
5168	static void build_zonelists(pg_data_t *pgdat)
5169	{
5170	int node, local_node;
5171	enum zone_type j;
5172	struct zonelist *zonelist;
5173
5174	local_node = pgdat->node_id;
5175
5176	zonelist = &pgdat->node_zonelists[ZONELIST_FALLBACK];
5177	j = build_zonelists_node(pgdat, zonelist, 0);
5178
5179	/*
5180	* Now we build the zonelist so that it contains the zones
5181	* of all the other nodes.
5182	* We don't want to pressure a particular node, so when
5183	* building the zones for node N, we make sure that the
5184	* zones coming right after the local ones are those from
5185	* node N+1 (modulo N)
5186	*/
5187	for (node = local_node + 1; node < MAX_NUMNODES; node++) {
5188	if (!node_online(node))
5189	continue;
5190	j = build_zonelists_node(NODE_DATA(node), zonelist, j);
5191	}
5192	for (node = 0; node < local_node; node++) {
5193	if (!node_online(node))
5194	continue;
5195	j = build_zonelists_node(NODE_DATA(node), zonelist, j);
5196	}
5197
5198	zonelist->_zonerefs[j].zone = NULL;
5199	zonelist->_zonerefs[j].zone_idx = 0;
5200	}
5201
5202	#endif /* CONFIG_NUMA */
5203
5204	/*
5205	* Boot pageset table. One per cpu which is going to be used for all
5206	* zones and all nodes. The parameters will be set in such a way
5207	* that an item put on a list will immediately be handed over to
5208	* the buddy list. This is safe since pageset manipulation is done
5209	* with interrupts disabled.
5210	*
5211	* The boot_pagesets must be kept even after bootup is complete for
5212	* unused processors and/or zones. They do play a role for bootstrapping
5213	* hotplugged processors.
5214	*
5215	* zoneinfo_show() and maybe other functions do
5216	* not check if the processor is online before following the pageset pointer.
5217	* Other parts of the kernel may not check if the zone is available.
5218	*/
5219	static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch);
5220	static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset);
5221	static void setup_zone_pageset(struct zone *zone);
5222
5223	/*
5224	* Global mutex to protect against size modification of zonelists
5225	* as well as to serialize pageset setup for the new populated zone.
5226	*/
5227	DEFINE_MUTEX(zonelists_mutex);
5228
5229	/* return values int ....just for stop_machine() */
5230	static int __build_all_zonelists(void *data)
5231	{
5232	int nid;
5233	int cpu;
5234	pg_data_t *self = data;
5235
5236	#ifdef CONFIG_NUMA
5237	memset(node_load, 0, sizeof(node_load));
5238	#endif
5239
5240	if (self && !node_online(self->node_id)) {
5241	build_zonelists(self);
5242	}
5243
5244	for_each_online_node(nid) {
5245	pg_data_t *pgdat = NODE_DATA(nid);
5246
5247	build_zonelists(pgdat);
5248	}
5249
5250	/*
5251	* Initialize the boot_pagesets that are going to be used
5252	* for bootstrapping processors. The real pagesets for
5253	* each zone will be allocated later when the per cpu
5254	* allocator is available.
5255	*
5256	* boot_pagesets are used also for bootstrapping offline
5257	* cpus if the system is already booted because the pagesets
5258	* are needed to initialize allocators on a specific cpu too.
5259	* F.e. the percpu allocator needs the page allocator which
5260	* needs the percpu allocator in order to allocate its pagesets
5261	* (a chicken-egg dilemma).
5262	*/
5263	for_each_possible_cpu(cpu) {
5264	setup_pageset(&per_cpu(boot_pageset, cpu), 0);
5265
5266	#ifdef CONFIG_HAVE_MEMORYLESS_NODES
5267	/*
5268	* We now know the "local memory node" for each node--
5269	* i.e., the node of the first zone in the generic zonelist.
5270	* Set up numa_mem percpu variable for on-line cpus. During
5271	* boot, only the boot cpu should be on-line; we'll init the
5272	* secondary cpus' numa_mem as they come on-line. During
5273	* node/memory hotplug, we'll fixup all on-line cpus.
5274	*/
5275	if (cpu_online(cpu))
5276	set_cpu_numa_mem(cpu, local_memory_node(cpu_to_node(cpu)));
5277	#endif
5278	}
5279
5280	return 0;
5281	}
5282
5283	static noinline void __init
5284	build_all_zonelists_init(void)
5285	{
5286	__build_all_zonelists(NULL);
5287	mminit_verify_zonelist();
5288	cpuset_init_current_mems_allowed();
5289	}
5290
5291	/*
5292	* Called with zonelists_mutex held always
5293	* unless system_state == SYSTEM_BOOTING.
5294	*
5295	* __ref due to (1) call of __meminit annotated setup_zone_pageset
5296	* [we're only called with non-NULL zone through __meminit paths] and
5297	* (2) call of __init annotated helper build_all_zonelists_init
5298	* [protected by SYSTEM_BOOTING].
5299	*/
5300	void __ref build_all_zonelists(pg_data_t *pgdat, struct zone *zone)
5301	{
5302	set_zonelist_order();
5303
5304	if (system_state == SYSTEM_BOOTING) {
5305	build_all_zonelists_init();
5306	} else {
5307	#ifdef CONFIG_MEMORY_HOTPLUG
5308	if (zone)
5309	setup_zone_pageset(zone);
5310	#endif
5311	/* we have to stop all cpus to guarantee there is no user
5312	of zonelist */
5313	stop_machine(__build_all_zonelists, pgdat, NULL);
5314	/* cpuset refresh routine should be here */
5315	}
5316	vm_total_pages = nr_free_pagecache_pages();
5317	/*
5318	* Disable grouping by mobility if the number of pages in the
5319	* system is too low to allow the mechanism to work. It would be
5320	* more accurate, but expensive to check per-zone. This check is
5321	* made on memory-hotadd so a system can start with mobility
5322	* disabled and enable it later
5323	*/
5324	if (vm_total_pages < (pageblock_nr_pages * MIGRATE_TYPES))
5325	page_group_by_mobility_disabled = 1;
5326	else
5327	page_group_by_mobility_disabled = 0;
5328
5329	pr_info("Built %i zonelists in %s order, mobility grouping %s. Total pages: %ld\n",
5330	nr_online_nodes,
5331	zonelist_order_name[current_zonelist_order],
5332	page_group_by_mobility_disabled ? "off" : "on",
5333	vm_total_pages);
5334	#ifdef CONFIG_NUMA
5335	pr_info("Policy zone: %s\n", zone_names[policy_zone]);
5336	#endif
5337	}
5338
5339	/*
5340	* Initially all pages are reserved - free ones are freed
5341	* up by free_all_bootmem() once the early boot process is
5342	* done. Non-atomic initialization, single-pass.
5343	*/
5344	void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
5345	unsigned long start_pfn, enum memmap_context context)
5346	{
5347	struct vmem_altmap *altmap = to_vmem_altmap(__pfn_to_phys(start_pfn));
5348	unsigned long end_pfn = start_pfn + size;
5349	pg_data_t *pgdat = NODE_DATA(nid);
5350	unsigned long pfn;
5351	unsigned long nr_initialised = 0;
5352	#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
5353	struct memblock_region *r = NULL, *tmp;
5354	#endif
5355
5356	if (highest_memmap_pfn < end_pfn - 1)
5357	highest_memmap_pfn = end_pfn - 1;
5358
5359	/*
5360	* Honor reservation requested by the driver for this ZONE_DEVICE
5361	* memory
5362	*/
5363	if (altmap && start_pfn == altmap->base_pfn)
5364	start_pfn += altmap->reserve;
5365
5366	for (pfn = start_pfn; pfn < end_pfn; pfn++) {
5367	/*
5368	* There can be holes in boot-time mem_map[]s handed to this
5369	* function. They do not exist on hotplugged memory.
5370	*/
5371	if (context != MEMMAP_EARLY)
5372	goto not_early;
5373
5374	if (!early_pfn_valid(pfn))
5375	continue;
5376	if (!early_pfn_in_nid(pfn, nid))
5377	continue;
5378	if (!update_defer_init(pgdat, pfn, end_pfn, &nr_initialised))
5379	break;
5380
5381	#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
5382	/*
5383	* Check given memblock attribute by firmware which can affect
5384	* kernel memory layout. If zone==ZONE_MOVABLE but memory is
5385	* mirrored, it's an overlapped memmap init. skip it.
5386	*/
5387	if (mirrored_kernelcore && zone == ZONE_MOVABLE) {
5388	if (!r || pfn >= memblock_region_memory_end_pfn(r)) {
5389	for_each_memblock(memory, tmp)
5390	if (pfn < memblock_region_memory_end_pfn(tmp))
5391	break;
5392	r = tmp;
5393	}
5394	if (pfn >= memblock_region_memory_base_pfn(r) &&
5395	memblock_is_mirror(r)) {
5396	/* already initialized as NORMAL */
5397	pfn = memblock_region_memory_end_pfn(r);
5398	continue;
5399	}
5400	}
5401	#endif
5402
5403	not_early:
5404	/*
5405	* Mark the block movable so that blocks are reserved for
5406	* movable at startup. This will force kernel allocations
5407	* to reserve their blocks rather than leaking throughout
5408	* the address space during boot when many long-lived
5409	* kernel allocations are made.
5410	*
5411	* bitmap is created for zone's valid pfn range. but memmap
5412	* can be created for invalid pages (for alignment)
5413	* check here not to call set_pageblock_migratetype() against
5414	* pfn out of zone.
5415	*/
5416	if (!(pfn & (pageblock_nr_pages - 1))) {
5417	struct page *page = pfn_to_page(pfn);
5418
5419	__init_single_page(page, pfn, zone, nid);
5420	set_pageblock_migratetype(page, MIGRATE_MOVABLE);
5421	} else {
5422	__init_single_pfn(pfn, zone, nid);
5423	}
5424	}
5425	}
5426
5427	static void __meminit zone_init_free_lists(struct zone *zone)
5428	{
5429	unsigned int order, t;
5430	for_each_migratetype_order(order, t) {
5431	INIT_LIST_HEAD(&zone->free_area[order].free_list[t]);
5432	zone->free_area[order].nr_free = 0;
5433	}
5434	}
5435
5436	#ifndef __HAVE_ARCH_MEMMAP_INIT
5437	#define memmap_init(size, nid, zone, start_pfn) \
5438	memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
5439	#endif
5440
5441	static int zone_batchsize(struct zone *zone)
5442	{
5443	#ifdef CONFIG_MMU
5444	int batch;
5445
5446	/*
5447	* The per-cpu-pages pools are set to around 1000th of the
5448	* size of the zone. But no more than 1/2 of a meg.
5449	*
5450	* OK, so we don't know how big the cache is. So guess.
5451	*/
5452	batch = zone->managed_pages / 1024;
5453	if (batch * PAGE_SIZE > 512 * 1024)
5454	batch = (512 * 1024) / PAGE_SIZE;
5455	batch /= 4; /* We effectively *= 4 below */
5456	if (batch < 1)
5457	batch = 1;
5458
5459	/*
5460	* Clamp the batch to a 2^n - 1 value. Having a power
5461	* of 2 value was found to be more likely to have
5462	* suboptimal cache aliasing properties in some cases.
5463	*
5464	* For example if 2 tasks are alternately allocating
5465	* batches of pages, one task can end up with a lot
5466	* of pages of one half of the possible page colors
5467	* and the other with pages of the other colors.
5468	*/
5469	batch = rounddown_pow_of_two(batch + batch/2) - 1;
5470
5471	return batch;
5472
5473	#else
5474	/* The deferral and batching of frees should be suppressed under NOMMU
5475	* conditions.
5476	*
5477	* The problem is that NOMMU needs to be able to allocate large chunks
5478	* of contiguous memory as there's no hardware page translation to
5479	* assemble apparent contiguous memory from discontiguous pages.
5480	*
5481	* Queueing large contiguous runs of pages for batching, however,
5482	* causes the pages to actually be freed in smaller chunks. As there
5483	* can be a significant delay between the individual batches being
5484	* recycled, this leads to the once large chunks of space being
5485	* fragmented and becoming unavailable for high-order allocations.
5486	*/
5487	return 0;
5488	#endif
5489	}
5490
5491	/*
5492	* pcp->high and pcp->batch values are related and dependent on one another:
5493	* ->batch must never be higher then ->high.
5494	* The following function updates them in a safe manner without read side
5495	* locking.
5496	*
5497	* Any new users of pcp->batch and pcp->high should ensure they can cope with
5498	* those fields changing asynchronously (acording the the above rule).
5499	*
5500	* mutex_is_locked(&pcp_batch_high_lock) required when calling this function
5501	* outside of boot time (or some other assurance that no concurrent updaters
5502	* exist).
5503	*/
5504	static void pageset_update(struct per_cpu_pages *pcp, unsigned long high,
5505	unsigned long batch)
5506	{
5507	/* start with a fail safe value for batch */
5508	pcp->batch = 1;
5509	smp_wmb();
5510
5511	/* Update high, then batch, in order */
5512	pcp->high = high;
5513	smp_wmb();
5514
5515	pcp->batch = batch;
5516	}
5517
5518	/* a companion to pageset_set_high() */
5519	static void pageset_set_batch(struct per_cpu_pageset *p, unsigned long batch)
5520	{
5521	pageset_update(&p->pcp, 6 * batch, max(1UL, 1 * batch));
5522	}
5523
5524	static void pageset_init(struct per_cpu_pageset *p)
5525	{
5526	struct per_cpu_pages *pcp;
5527	int migratetype;
5528
5529	memset(p, 0, sizeof(*p));
5530
5531	pcp = &p->pcp;
5532	pcp->count = 0;
5533	for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++)
5534	INIT_LIST_HEAD(&pcp->lists[migratetype]);
5535	}
5536
5537	static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
5538	{
5539	pageset_init(p);
5540	pageset_set_batch(p, batch);
5541	}
5542
5543	/*
5544	* pageset_set_high() sets the high water mark for hot per_cpu_pagelist
5545	* to the value high for the pageset p.
5546	*/
5547	static void pageset_set_high(struct per_cpu_pageset *p,
5548	unsigned long high)
5549	{
5550	unsigned long batch = max(1UL, high / 4);
5551	if ((high / 4) > (PAGE_SHIFT * 8))
5552	batch = PAGE_SHIFT * 8;
5553
5554	pageset_update(&p->pcp, high, batch);
5555	}
5556
5557	static void pageset_set_high_and_batch(struct zone *zone,
5558	struct per_cpu_pageset *pcp)
5559	{
5560	if (percpu_pagelist_fraction)
5561	pageset_set_high(pcp,
5562	(zone->managed_pages /
5563	percpu_pagelist_fraction));
5564	else
5565	pageset_set_batch(pcp, zone_batchsize(zone));
5566	}
5567
5568	static void __meminit zone_pageset_init(struct zone *zone, int cpu)
5569	{
5570	struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu);
5571
5572	pageset_init(pcp);
5573	pageset_set_high_and_batch(zone, pcp);
5574	}
5575
5576	static void __meminit setup_zone_pageset(struct zone *zone)
5577	{
5578	int cpu;
5579	zone->pageset = alloc_percpu(struct per_cpu_pageset);
5580	for_each_possible_cpu(cpu)
5581	zone_pageset_init(zone, cpu);
5582	}
5583
5584	/*
5585	* Allocate per cpu pagesets and initialize them.
5586	* Before this call only boot pagesets were available.
5587	*/
5588	void __init setup_per_cpu_pageset(void)
5589	{
5590	struct pglist_data *pgdat;
5591	struct zone *zone;
5592
5593	for_each_populated_zone(zone)
5594	setup_zone_pageset(zone);
5595
5596	for_each_online_pgdat(pgdat)
5597	pgdat->per_cpu_nodestats =
5598	alloc_percpu(struct per_cpu_nodestat);
5599	}
5600
5601	static __meminit void zone_pcp_init(struct zone *zone)
5602	{
5603	/*
5604	* per cpu subsystem is not up at this point. The following code
5605	* relies on the ability of the linker to provide the
5606	* offset of a (static) per cpu variable into the per cpu area.
5607	*/
5608	zone->pageset = &boot_pageset;
5609
5610	if (populated_zone(zone))
5611	printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%u\n",
5612	zone->name, zone->present_pages,
5613	zone_batchsize(zone));
5614	}
5615
5616	int __meminit init_currently_empty_zone(struct zone *zone,
5617	unsigned long zone_start_pfn,
5618	unsigned long size)
5619	{
5620	struct pglist_data *pgdat = zone->zone_pgdat;
5621
5622	pgdat->nr_zones = zone_idx(zone) + 1;
5623
5624	zone->zone_start_pfn = zone_start_pfn;
5625
5626	mminit_dprintk(MMINIT_TRACE, "memmap_init",
5627	"Initialising map node %d zone %lu pfns %lu -> %lu\n",
5628	pgdat->node_id,
5629	(unsigned long)zone_idx(zone),
5630	zone_start_pfn, (zone_start_pfn + size));
5631
5632	zone_init_free_lists(zone);
5633	zone->initialized = 1;
5634
5635	return 0;
5636	}
5637
5638	#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
5639	#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
5640
5641	/*
5642	* Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
5643	*/
5644	int __meminit __early_pfn_to_nid(unsigned long pfn,
5645	struct mminit_pfnnid_cache *state)
5646	{
5647	unsigned long start_pfn, end_pfn;
5648	int nid;
5649
5650	if (state->last_start <= pfn && pfn < state->last_end)
5651	return state->last_nid;
5652
5653	nid = memblock_search_pfn_nid(pfn, &start_pfn, &end_pfn);
5654	if (nid != -1) {
5655	state->last_start = start_pfn;
5656	state->last_end = end_pfn;
5657	state->last_nid = nid;
5658	}
5659
5660	return nid;
5661	}
5662	#endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
5663
5664	/**
5665	* free_bootmem_with_active_regions - Call memblock_free_early_nid for each active range
5666	* @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
5667	* @max_low_pfn: The highest PFN that will be passed to memblock_free_early_nid
5668	*
5669	* If an architecture guarantees that all ranges registered contain no holes
5670	* and may be freed, this this function may be used instead of calling
5671	* memblock_free_early_nid() manually.
5672	*/
5673	void __init free_bootmem_with_active_regions(int nid, unsigned long max_low_pfn)
5674	{
5675	unsigned long start_pfn, end_pfn;
5676	int i, this_nid;
5677
5678	for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, &this_nid) {
5679	start_pfn = min(start_pfn, max_low_pfn);
5680	end_pfn = min(end_pfn, max_low_pfn);
5681
5682	if (start_pfn < end_pfn)
5683	memblock_free_early_nid(PFN_PHYS(start_pfn),
5684	(end_pfn - start_pfn) << PAGE_SHIFT,
5685	this_nid);
5686	}
5687	}
5688
5689	/**
5690	* sparse_memory_present_with_active_regions - Call memory_present for each active range
5691	* @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
5692	*
5693	* If an architecture guarantees that all ranges registered contain no holes and may
5694	* be freed, this function may be used instead of calling memory_present() manually.
5695	*/
5696	void __init sparse_memory_present_with_active_regions(int nid)
5697	{
5698	unsigned long start_pfn, end_pfn;
5699	int i, this_nid;
5700
5701	for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, &this_nid)
5702	memory_present(this_nid, start_pfn, end_pfn);
5703	}
5704
5705	/**
5706	* get_pfn_range_for_nid - Return the start and end page frames for a node
5707	* @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
5708	* @start_pfn: Passed by reference. On return, it will have the node start_pfn.
5709	* @end_pfn: Passed by reference. On return, it will have the node end_pfn.
5710	*
5711	* It returns the start and end page frame of a node based on information
5712	* provided by memblock_set_node(). If called for a node
5713	* with no available memory, a warning is printed and the start and end
5714	* PFNs will be 0.
5715	*/
5716	void __meminit get_pfn_range_for_nid(unsigned int nid,
5717	unsigned long *start_pfn, unsigned long *end_pfn)
5718	{
5719	unsigned long this_start_pfn, this_end_pfn;
5720	int i;
5721
5722	*start_pfn = -1UL;
5723	*end_pfn = 0;
5724
5725	for_each_mem_pfn_range(i, nid, &this_start_pfn, &this_end_pfn, NULL) {
5726	*start_pfn = min(*start_pfn, this_start_pfn);
5727	*end_pfn = max(*end_pfn, this_end_pfn);
5728	}
5729
5730	if (*start_pfn == -1UL)
5731	*start_pfn = 0;
5732	}
5733
5734	/*
5735	* This finds a zone that can be used for ZONE_MOVABLE pages. The
5736	* assumption is made that zones within a node are ordered in monotonic
5737	* increasing memory addresses so that the "highest" populated zone is used
5738	*/
5739	static void __init find_usable_zone_for_movable(void)
5740	{
5741	int zone_index;
5742	for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) {
5743	if (zone_index == ZONE_MOVABLE)
5744	continue;
5745
5746	if (arch_zone_highest_possible_pfn[zone_index] >
5747	arch_zone_lowest_possible_pfn[zone_index])
5748	break;
5749	}
5750
5751	VM_BUG_ON(zone_index == -1);
5752	movable_zone = zone_index;
5753	}
5754
5755	/*
5756	* The zone ranges provided by the architecture do not include ZONE_MOVABLE
5757	* because it is sized independent of architecture. Unlike the other zones,
5758	* the starting point for ZONE_MOVABLE is not fixed. It may be different
5759	* in each node depending on the size of each node and how evenly kernelcore
5760	* is distributed. This helper function adjusts the zone ranges
5761	* provided by the architecture for a given node by using the end of the
5762	* highest usable zone for ZONE_MOVABLE. This preserves the assumption that
5763	* zones within a node are in order of monotonic increases memory addresses
5764	*/
5765	static void __meminit adjust_zone_range_for_zone_movable(int nid,
5766	unsigned long zone_type,
5767	unsigned long node_start_pfn,
5768	unsigned long node_end_pfn,
5769	unsigned long *zone_start_pfn,
5770	unsigned long *zone_end_pfn)
5771	{
5772	/* Only adjust if ZONE_MOVABLE is on this node */
5773	if (zone_movable_pfn[nid]) {
5774	/* Size ZONE_MOVABLE */
5775	if (zone_type == ZONE_MOVABLE) {
5776	*zone_start_pfn = zone_movable_pfn[nid];
5777	*zone_end_pfn = min(node_end_pfn,
5778	arch_zone_highest_possible_pfn[movable_zone]);
5779
5780	/* Adjust for ZONE_MOVABLE starting within this range */
5781	} else if (!mirrored_kernelcore &&
5782	*zone_start_pfn < zone_movable_pfn[nid] &&
5783	*zone_end_pfn > zone_movable_pfn[nid]) {
5784	*zone_end_pfn = zone_movable_pfn[nid];
5785
5786	/* Check if this whole range is within ZONE_MOVABLE */
5787	} else if (*zone_start_pfn >= zone_movable_pfn[nid])
5788	*zone_start_pfn = *zone_end_pfn;
5789	}
5790	}
5791
5792	/*
5793	* Return the number of pages a zone spans in a node, including holes
5794	* present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
5795	*/
5796	static unsigned long __meminit zone_spanned_pages_in_node(int nid,
5797	unsigned long zone_type,
5798	unsigned long node_start_pfn,
5799	unsigned long node_end_pfn,
5800	unsigned long *zone_start_pfn,
5801	unsigned long *zone_end_pfn,
5802	unsigned long *ignored)
5803	{
5804	/* When hotadd a new node from cpu_up(), the node should be empty */
5805	if (!node_start_pfn && !node_end_pfn)
5806	return 0;
5807
5808	/* Get the start and end of the zone */
5809	*zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type];
5810	*zone_end_pfn = arch_zone_highest_possible_pfn[zone_type];
5811	adjust_zone_range_for_zone_movable(nid, zone_type,
5812	node_start_pfn, node_end_pfn,
5813	zone_start_pfn, zone_end_pfn);
5814
5815	/* Check that this node has pages within the zone's required range */
5816	if (*zone_end_pfn < node_start_pfn || *zone_start_pfn > node_end_pfn)
5817	return 0;
5818
5819	/* Move the zone boundaries inside the node if necessary */
5820	*zone_end_pfn = min(*zone_end_pfn, node_end_pfn);
5821	*zone_start_pfn = max(*zone_start_pfn, node_start_pfn);
5822
5823	/* Return the spanned pages */
5824	return *zone_end_pfn - *zone_start_pfn;
5825	}
5826
5827	/*
5828	* Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
5829	* then all holes in the requested range will be accounted for.
5830	*/
5831	unsigned long __meminit __absent_pages_in_range(int nid,
5832	unsigned long range_start_pfn,
5833	unsigned long range_end_pfn)
5834	{
5835	unsigned long nr_absent = range_end_pfn - range_start_pfn;
5836	unsigned long start_pfn, end_pfn;
5837	int i;
5838
5839	for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
5840	start_pfn = clamp(start_pfn, range_start_pfn, range_end_pfn);
5841	end_pfn = clamp(end_pfn, range_start_pfn, range_end_pfn);
5842	nr_absent -= end_pfn - start_pfn;
5843	}
5844	return nr_absent;
5845	}
5846
5847	/**
5848	* absent_pages_in_range - Return number of page frames in holes within a range
5849	* @start_pfn: The start PFN to start searching for holes
5850	* @end_pfn: The end PFN to stop searching for holes
5851	*
5852	* It returns the number of pages frames in memory holes within a range.
5853	*/
5854	unsigned long __init absent_pages_in_range(unsigned long start_pfn,
5855	unsigned long end_pfn)
5856	{
5857	return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn);
5858	}
5859
5860	/* Return the number of page frames in holes in a zone on a node */
5861	static unsigned long __meminit zone_absent_pages_in_node(int nid,
5862	unsigned long zone_type,
5863	unsigned long node_start_pfn,
5864	unsigned long node_end_pfn,
5865	unsigned long *ignored)
5866	{
5867	unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type];
5868	unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type];
5869	unsigned long zone_start_pfn, zone_end_pfn;
5870	unsigned long nr_absent;
5871
5872	/* When hotadd a new node from cpu_up(), the node should be empty */
5873	if (!node_start_pfn && !node_end_pfn)
5874	return 0;
5875
5876	zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high);
5877	zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high);
5878
5879	adjust_zone_range_for_zone_movable(nid, zone_type,
5880	node_start_pfn, node_end_pfn,
5881	&zone_start_pfn, &zone_end_pfn);
5882	nr_absent = __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
5883
5884	/*
5885	* ZONE_MOVABLE handling.
5886	* Treat pages to be ZONE_MOVABLE in ZONE_NORMAL as absent pages
5887	* and vice versa.
5888	*/
5889	if (mirrored_kernelcore && zone_movable_pfn[nid]) {
5890	unsigned long start_pfn, end_pfn;
5891	struct memblock_region *r;
5892
5893	for_each_memblock(memory, r) {
5894	start_pfn = clamp(memblock_region_memory_base_pfn(r),
5895	zone_start_pfn, zone_end_pfn);
5896	end_pfn = clamp(memblock_region_memory_end_pfn(r),
5897	zone_start_pfn, zone_end_pfn);
5898
5899	if (zone_type == ZONE_MOVABLE &&
5900	memblock_is_mirror(r))
5901	nr_absent += end_pfn - start_pfn;
5902
5903	if (zone_type == ZONE_NORMAL &&
5904	!memblock_is_mirror(r))
5905	nr_absent += end_pfn - start_pfn;
5906	}
5907	}
5908
5909	return nr_absent;
5910	}
5911
5912	#else /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
5913	static inline unsigned long __meminit zone_spanned_pages_in_node(int nid,
5914	unsigned long zone_type,
5915	unsigned long node_start_pfn,
5916	unsigned long node_end_pfn,
5917	unsigned long *zone_start_pfn,
5918	unsigned long *zone_end_pfn,
5919	unsigned long *zones_size)
5920	{
5921	unsigned int zone;
5922
5923	*zone_start_pfn = node_start_pfn;
5924	for (zone = 0; zone < zone_type; zone++)
5925	*zone_start_pfn += zones_size[zone];
5926
5927	*zone_end_pfn = *zone_start_pfn + zones_size[zone_type];
5928
5929	return zones_size[zone_type];
5930	}
5931
5932	static inline unsigned long __meminit zone_absent_pages_in_node(int nid,
5933	unsigned long zone_type,
5934	unsigned long node_start_pfn,
5935	unsigned long node_end_pfn,
5936	unsigned long *zholes_size)
5937	{
5938	if (!zholes_size)
5939	return 0;
5940
5941	return zholes_size[zone_type];
5942	}
5943
5944	#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
5945
5946	static void __meminit calculate_node_totalpages(struct pglist_data *pgdat,
5947	unsigned long node_start_pfn,
5948	unsigned long node_end_pfn,
5949	unsigned long *zones_size,
5950	unsigned long *zholes_size)
5951	{
5952	unsigned long realtotalpages = 0, totalpages = 0;
5953	enum zone_type i;
5954
5955	for (i = 0; i < MAX_NR_ZONES; i++) {
5956	struct zone *zone = pgdat->node_zones + i;
5957	unsigned long zone_start_pfn, zone_end_pfn;
5958	unsigned long size, real_size;
5959
5960	size = zone_spanned_pages_in_node(pgdat->node_id, i,
5961	node_start_pfn,
5962	node_end_pfn,
5963	&zone_start_pfn,
5964	&zone_end_pfn,
5965	zones_size);
5966	real_size = size - zone_absent_pages_in_node(pgdat->node_id, i,
5967	node_start_pfn, node_end_pfn,
5968	zholes_size);
5969	if (size)
5970	zone->zone_start_pfn = zone_start_pfn;
5971	else
5972	zone->zone_start_pfn = 0;
5973	zone->spanned_pages = size;
5974	zone->present_pages = real_size;
5975
5976	totalpages += size;
5977	realtotalpages += real_size;
5978	}
5979
5980	pgdat->node_spanned_pages = totalpages;
5981	pgdat->node_present_pages = realtotalpages;
5982	printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id,
5983	realtotalpages);
5984	}
5985
5986	#ifndef CONFIG_SPARSEMEM
5987	/*
5988	* Calculate the size of the zone->blockflags rounded to an unsigned long
5989	* Start by making sure zonesize is a multiple of pageblock_order by rounding
5990	* up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
5991	* round what is now in bits to nearest long in bits, then return it in
5992	* bytes.
5993	*/
5994	static unsigned long __init usemap_size(unsigned long zone_start_pfn, unsigned long zonesize)
5995	{
5996	unsigned long usemapsize;
5997
5998	zonesize += zone_start_pfn & (pageblock_nr_pages-1);
5999	usemapsize = roundup(zonesize, pageblock_nr_pages);
6000	usemapsize = usemapsize >> pageblock_order;
6001	usemapsize *= NR_PAGEBLOCK_BITS;
6002	usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long));
6003
6004	return usemapsize / 8;
6005	}
6006
6007	static void __init setup_usemap(struct pglist_data *pgdat,
6008	struct zone *zone,
6009	unsigned long zone_start_pfn,
6010	unsigned long zonesize)
6011	{
6012	unsigned long usemapsize = usemap_size(zone_start_pfn, zonesize);
6013	zone->pageblock_flags = NULL;
6014	if (usemapsize)
6015	zone->pageblock_flags =
6016	memblock_virt_alloc_node_nopanic(usemapsize,
6017	pgdat->node_id);
6018	}
6019	#else
6020	static inline void setup_usemap(struct pglist_data *pgdat, struct zone *zone,
6021	unsigned long zone_start_pfn, unsigned long zonesize) {}
6022	#endif /* CONFIG_SPARSEMEM */
6023
6024	#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
6025
6026	/* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
6027	void __paginginit set_pageblock_order(void)
6028	{
6029	unsigned int order;
6030
6031	/* Check that pageblock_nr_pages has not already been setup */
6032	if (pageblock_order)
6033	return;
6034
6035	if (HPAGE_SHIFT > PAGE_SHIFT)
6036	order = HUGETLB_PAGE_ORDER;
6037	else
6038	order = MAX_ORDER - 1;
6039
6040	/*
6041	* Assume the largest contiguous order of interest is a huge page.
6042	* This value may be variable depending on boot parameters on IA64 and
6043	* powerpc.
6044	*/
6045	pageblock_order = order;
6046	}
6047	#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
6048
6049	/*
6050	* When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
6051	* is unused as pageblock_order is set at compile-time. See
6052	* include/linux/pageblock-flags.h for the values of pageblock_order based on
6053	* the kernel config
6054	*/
6055	void __paginginit set_pageblock_order(void)
6056	{
6057	}
6058
6059	#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
6060
6061	static unsigned long __paginginit calc_memmap_size(unsigned long spanned_pages,
6062	unsigned long present_pages)
6063	{
6064	unsigned long pages = spanned_pages;
6065
6066	/*
6067	* Provide a more accurate estimation if there are holes within
6068	* the zone and SPARSEMEM is in use. If there are holes within the
6069	* zone, each populated memory region may cost us one or two extra
6070	* memmap pages due to alignment because memmap pages for each
6071	* populated regions may not naturally algined on page boundary.
6072	* So the (present_pages >> 4) heuristic is a tradeoff for that.
6073	*/
6074	if (spanned_pages > present_pages + (present_pages >> 4) &&
6075	IS_ENABLED(CONFIG_SPARSEMEM))
6076	pages = present_pages;
6077
6078	return PAGE_ALIGN(pages * sizeof(struct page)) >> PAGE_SHIFT;
6079	}
6080
6081	/*
6082	* Set up the zone data structures:
6083	* - mark all pages reserved
6084	* - mark all memory queues empty
6085	* - clear the memory bitmaps
6086	*
6087	* NOTE: pgdat should get zeroed by caller.
6088	*/
6089	static void __paginginit free_area_init_core(struct pglist_data *pgdat)
6090	{
6091	enum zone_type j;
6092	int nid = pgdat->node_id;
6093	int ret;
6094
6095	pgdat_resize_init(pgdat);
6096	#ifdef CONFIG_NUMA_BALANCING
6097	spin_lock_init(&pgdat->numabalancing_migrate_lock);
6098	pgdat->numabalancing_migrate_nr_pages = 0;
6099	pgdat->numabalancing_migrate_next_window = jiffies;
6100	#endif
6101	#ifdef CONFIG_TRANSPARENT_HUGEPAGE
6102	spin_lock_init(&pgdat->split_queue_lock);
6103	INIT_LIST_HEAD(&pgdat->split_queue);
6104	pgdat->split_queue_len = 0;
6105	#endif
6106	init_waitqueue_head(&pgdat->kswapd_wait);
6107	init_waitqueue_head(&pgdat->pfmemalloc_wait);
6108	#ifdef CONFIG_COMPACTION
6109	init_waitqueue_head(&pgdat->kcompactd_wait);
6110	#endif
6111	pgdat_page_ext_init(pgdat);
6112	spin_lock_init(&pgdat->lru_lock);
6113	lruvec_init(node_lruvec(pgdat));
6114
6115	for (j = 0; j < MAX_NR_ZONES; j++) {
6116	struct zone *zone = pgdat->node_zones + j;
6117	unsigned long size, realsize, freesize, memmap_pages;
6118	unsigned long zone_start_pfn = zone->zone_start_pfn;
6119
6120	size = zone->spanned_pages;
6121	realsize = freesize = zone->present_pages;
6122
6123	/*
6124	* Adjust freesize so that it accounts for how much memory
6125	* is used by this zone for memmap. This affects the watermark
6126	* and per-cpu initialisations
6127	*/
6128	memmap_pages = calc_memmap_size(size, realsize);
6129	if (!is_highmem_idx(j)) {
6130	if (freesize >= memmap_pages) {
6131	freesize -= memmap_pages;
6132	if (memmap_pages)
6133	printk(KERN_DEBUG
6134	" %s zone: %lu pages used for memmap\n",
6135	zone_names[j], memmap_pages);
6136	} else
6137	pr_warn(" %s zone: %lu pages exceeds freesize %lu\n",
6138	zone_names[j], memmap_pages, freesize);
6139	}
6140
6141	/* Account for reserved pages */
6142	if (j == 0 && freesize > dma_reserve) {
6143	freesize -= dma_reserve;
6144	printk(KERN_DEBUG " %s zone: %lu pages reserved\n",
6145	zone_names[0], dma_reserve);
6146	}
6147
6148	if (!is_highmem_idx(j))
6149	nr_kernel_pages += freesize;
6150	/* Charge for highmem memmap if there are enough kernel pages */
6151	else if (nr_kernel_pages > memmap_pages * 2)
6152	nr_kernel_pages -= memmap_pages;
6153	nr_all_pages += freesize;
6154
6155	/*
6156	* Set an approximate value for lowmem here, it will be adjusted
6157	* when the bootmem allocator frees pages into the buddy system.
6158	* And all highmem pages will be managed by the buddy system.
6159	*/
6160	zone->managed_pages = is_highmem_idx(j) ? realsize : freesize;
6161	#ifdef CONFIG_NUMA
6162	zone->node = nid;
6163	#endif
6164	zone->name = zone_names[j];
6165	zone->zone_pgdat = pgdat;
6166	spin_lock_init(&zone->lock);
6167	zone_seqlock_init(zone);
6168	zone_pcp_init(zone);
6169
6170	if (!size)
6171	continue;
6172
6173	set_pageblock_order();
6174	setup_usemap(pgdat, zone, zone_start_pfn, size);
6175	ret = init_currently_empty_zone(zone, zone_start_pfn, size);
6176	BUG_ON(ret);
6177	memmap_init(size, nid, j, zone_start_pfn);
6178	}
6179	}
6180
6181	static void __ref alloc_node_mem_map(struct pglist_data *pgdat)
6182	{
6183	unsigned long __maybe_unused start = 0;
6184	unsigned long __maybe_unused offset = 0;
6185
6186	/* Skip empty nodes */
6187	if (!pgdat->node_spanned_pages)
6188	return;
6189
6190	#ifdef CONFIG_FLAT_NODE_MEM_MAP
6191	start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1);
6192	offset = pgdat->node_start_pfn - start;
6193	/* ia64 gets its own node_mem_map, before this, without bootmem */
6194	if (!pgdat->node_mem_map) {
6195	unsigned long size, end;
6196	struct page *map;
6197
6198	/*
6199	* The zone's endpoints aren't required to be MAX_ORDER
6200	* aligned but the node_mem_map endpoints must be in order
6201	* for the buddy allocator to function correctly.
6202	*/
6203	end = pgdat_end_pfn(pgdat);
6204	end = ALIGN(end, MAX_ORDER_NR_PAGES);
6205	size = (end - start) * sizeof(struct page);
6206	map = alloc_remap(pgdat->node_id, size);
6207	if (!map)
6208	map = memblock_virt_alloc_node_nopanic(size,
6209	pgdat->node_id);
6210	pgdat->node_mem_map = map + offset;
6211	}
6212	#ifndef CONFIG_NEED_MULTIPLE_NODES
6213	/*
6214	* With no DISCONTIG, the global mem_map is just set as node 0's
6215	*/
6216	if (pgdat == NODE_DATA(0)) {
6217	mem_map = NODE_DATA(0)->node_mem_map;
6218	#if defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) || defined(CONFIG_FLATMEM)
6219	if (page_to_pfn(mem_map) != pgdat->node_start_pfn)
6220	mem_map -= offset;
6221	#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
6222	}
6223	#endif
6224	#endif /* CONFIG_FLAT_NODE_MEM_MAP */
6225	}
6226
6227	void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
6228	unsigned long node_start_pfn, unsigned long *zholes_size)
6229	{
6230	pg_data_t *pgdat = NODE_DATA(nid);
6231	unsigned long start_pfn = 0;
6232	unsigned long end_pfn = 0;
6233
6234	/* pg_data_t should be reset to zero when it's allocated */
6235	WARN_ON(pgdat->nr_zones || pgdat->kswapd_classzone_idx);
6236
6237	pgdat->node_id = nid;
6238	pgdat->node_start_pfn = node_start_pfn;
6239	pgdat->per_cpu_nodestats = NULL;
6240	#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
6241	get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
6242	pr_info("Initmem setup node %d [mem %#018Lx-%#018Lx]\n", nid,
6243	(u64)start_pfn << PAGE_SHIFT,
6244	end_pfn ? ((u64)end_pfn << PAGE_SHIFT) - 1 : 0);
6245	#else
6246	start_pfn = node_start_pfn;
6247	#endif
6248	calculate_node_totalpages(pgdat, start_pfn, end_pfn,
6249	zones_size, zholes_size);
6250
6251	alloc_node_mem_map(pgdat);
6252	#ifdef CONFIG_FLAT_NODE_MEM_MAP
6253	printk(KERN_DEBUG "free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n",
6254	nid, (unsigned long)pgdat,
6255	(unsigned long)pgdat->node_mem_map);
6256	#endif
6257
6258	reset_deferred_meminit(pgdat);
6259	free_area_init_core(pgdat);
6260	}
6261
6262	#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
6263
6264	#if MAX_NUMNODES > 1
6265	/*
6266	* Figure out the number of possible node ids.
6267	*/
6268	void __init setup_nr_node_ids(void)
6269	{
6270	unsigned int highest;
6271
6272	highest = find_last_bit(node_possible_map.bits, MAX_NUMNODES);
6273	nr_node_ids = highest + 1;
6274	}
6275	#endif
6276
6277	/**
6278	* node_map_pfn_alignment - determine the maximum internode alignment
6279	*
6280	* This function should be called after node map is populated and sorted.
6281	* It calculates the maximum power of two alignment which can distinguish
6282	* all the nodes.
6283	*
6284	* For example, if all nodes are 1GiB and aligned to 1GiB, the return value
6285	* would indicate 1GiB alignment with (1 << (30 - PAGE_SHIFT)). If the
6286	* nodes are shifted by 256MiB, 256MiB. Note that if only the last node is
6287	* shifted, 1GiB is enough and this function will indicate so.
6288	*
6289	* This is used to test whether pfn -> nid mapping of the chosen memory
6290	* model has fine enough granularity to avoid incorrect mapping for the
6291	* populated node map.
6292	*
6293	* Returns the determined alignment in pfn's. 0 if there is no alignment
6294	* requirement (single node).
6295	*/
6296	unsigned long __init node_map_pfn_alignment(void)
6297	{
6298	unsigned long accl_mask = 0, last_end = 0;
6299	unsigned long start, end, mask;
6300	int last_nid = -1;
6301	int i, nid;
6302
6303	for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, &nid) {
6304	if (!start || last_nid < 0 || last_nid == nid) {
6305	last_nid = nid;
6306	last_end = end;
6307	continue;
6308	}
6309
6310	/*
6311	* Start with a mask granular enough to pin-point to the
6312	* start pfn and tick off bits one-by-one until it becomes
6313	* too coarse to separate the current node from the last.
6314	*/
6315	mask = ~((1 << __ffs(start)) - 1);
6316	while (mask && last_end <= (start & (mask << 1)))
6317	mask <<= 1;
6318
6319	/* accumulate all internode masks */
6320	accl_mask |= mask;
6321	}
6322
6323	/* convert mask to number of pages */
6324	return ~accl_mask + 1;
6325	}
6326
6327	/* Find the lowest pfn for a node */
6328	static unsigned long __init find_min_pfn_for_node(int nid)
6329	{
6330	unsigned long min_pfn = ULONG_MAX;
6331	unsigned long start_pfn;
6332	int i;
6333
6334	for_each_mem_pfn_range(i, nid, &start_pfn, NULL, NULL)
6335	min_pfn = min(min_pfn, start_pfn);
6336
6337	if (min_pfn == ULONG_MAX) {
6338	pr_warn("Could not find start_pfn for node %d\n", nid);
6339	return 0;
6340	}
6341
6342	return min_pfn;
6343	}
6344
6345	/**
6346	* find_min_pfn_with_active_regions - Find the minimum PFN registered
6347	*
6348	* It returns the minimum PFN based on information provided via
6349	* memblock_set_node().
6350	*/
6351	unsigned long __init find_min_pfn_with_active_regions(void)
6352	{
6353	return find_min_pfn_for_node(MAX_NUMNODES);
6354	}
6355
6356	/*
6357	* early_calculate_totalpages()
6358	* Sum pages in active regions for movable zone.
6359	* Populate N_MEMORY for calculating usable_nodes.
6360	*/
6361	static unsigned long __init early_calculate_totalpages(void)
6362	{
6363	unsigned long totalpages = 0;
6364	unsigned long start_pfn, end_pfn;
6365	int i, nid;
6366
6367	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) {
6368	unsigned long pages = end_pfn - start_pfn;
6369
6370	totalpages += pages;
6371	if (pages)
6372	node_set_state(nid, N_MEMORY);
6373	}
6374	return totalpages;
6375	}
6376
6377	/*
6378	* Find the PFN the Movable zone begins in each node. Kernel memory
6379	* is spread evenly between nodes as long as the nodes have enough
6380	* memory. When they don't, some nodes will have more kernelcore than
6381	* others
6382	*/
6383	static void __init find_zone_movable_pfns_for_nodes(void)
6384	{
6385	int i, nid;
6386	unsigned long usable_startpfn;
6387	unsigned long kernelcore_node, kernelcore_remaining;
6388	/* save the state before borrow the nodemask */
6389	nodemask_t saved_node_state = node_states[N_MEMORY];
6390	unsigned long totalpages = early_calculate_totalpages();
6391	int usable_nodes = nodes_weight(node_states[N_MEMORY]);
6392	struct memblock_region *r;
6393
6394	/* Need to find movable_zone earlier when movable_node is specified. */
6395	find_usable_zone_for_movable();
6396
6397	/*
6398	* If movable_node is specified, ignore kernelcore and movablecore
6399	* options.
6400	*/
6401	if (movable_node_is_enabled()) {
6402	for_each_memblock(memory, r) {
6403	if (!memblock_is_hotpluggable(r))
6404	continue;
6405
6406	nid = r->nid;
6407
6408	usable_startpfn = PFN_DOWN(r->base);
6409	zone_movable_pfn[nid] = zone_movable_pfn[nid] ?
6410	min(usable_startpfn, zone_movable_pfn[nid]) :
6411	usable_startpfn;
6412	}
6413
6414	goto out2;
6415	}
6416
6417	/*
6418	* If kernelcore=mirror is specified, ignore movablecore option
6419	*/
6420	if (mirrored_kernelcore) {
6421	bool mem_below_4gb_not_mirrored = false;
6422
6423	for_each_memblock(memory, r) {
6424	if (memblock_is_mirror(r))
6425	continue;
6426
6427	nid = r->nid;
6428
6429	usable_startpfn = memblock_region_memory_base_pfn(r);
6430
6431	if (usable_startpfn < 0x100000) {
6432	mem_below_4gb_not_mirrored = true;
6433	continue;
6434	}
6435
6436	zone_movable_pfn[nid] = zone_movable_pfn[nid] ?
6437	min(usable_startpfn, zone_movable_pfn[nid]) :
6438	usable_startpfn;
6439	}
6440
6441	if (mem_below_4gb_not_mirrored)
6442	pr_warn("This configuration results in unmirrored kernel memory.");
6443
6444	goto out2;
6445	}
6446
6447	/*
6448	* If movablecore=nn[KMG] was specified, calculate what size of
6449	* kernelcore that corresponds so that memory usable for
6450	* any allocation type is evenly spread. If both kernelcore
6451	* and movablecore are specified, then the value of kernelcore
6452	* will be used for required_kernelcore if it's greater than
6453	* what movablecore would have allowed.
6454	*/
6455	if (required_movablecore) {
6456	unsigned long corepages;
6457
6458	/*
6459	* Round-up so that ZONE_MOVABLE is at least as large as what
6460	* was requested by the user
6461	*/
6462	required_movablecore =
6463	roundup(required_movablecore, MAX_ORDER_NR_PAGES);
6464	required_movablecore = min(totalpages, required_movablecore);
6465	corepages = totalpages - required_movablecore;
6466
6467	required_kernelcore = max(required_kernelcore, corepages);
6468	}
6469
6470	/*
6471	* If kernelcore was not specified or kernelcore size is larger
6472	* than totalpages, there is no ZONE_MOVABLE.
6473	*/
6474	if (!required_kernelcore || required_kernelcore >= totalpages)
6475	goto out;
6476
6477	/* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
6478	usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone];
6479
6480	restart:
6481	/* Spread kernelcore memory as evenly as possible throughout nodes */
6482	kernelcore_node = required_kernelcore / usable_nodes;
6483	for_each_node_state(nid, N_MEMORY) {
6484	unsigned long start_pfn, end_pfn;
6485
6486	/*
6487	* Recalculate kernelcore_node if the division per node
6488	* now exceeds what is necessary to satisfy the requested
6489	* amount of memory for the kernel
6490	*/
6491	if (required_kernelcore < kernelcore_node)
6492	kernelcore_node = required_kernelcore / usable_nodes;
6493
6494	/*
6495	* As the map is walked, we track how much memory is usable
6496	* by the kernel using kernelcore_remaining. When it is
6497	* 0, the rest of the node is usable by ZONE_MOVABLE
6498	*/
6499	kernelcore_remaining = kernelcore_node;
6500
6501	/* Go through each range of PFNs within this node */
6502	for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
6503	unsigned long size_pages;
6504
6505	start_pfn = max(start_pfn, zone_movable_pfn[nid]);
6506	if (start_pfn >= end_pfn)
6507	continue;
6508
6509	/* Account for what is only usable for kernelcore */
6510	if (start_pfn < usable_startpfn) {
6511	unsigned long kernel_pages;
6512	kernel_pages = min(end_pfn, usable_startpfn)
6513	- start_pfn;
6514
6515	kernelcore_remaining -= min(kernel_pages,
6516	kernelcore_remaining);
6517	required_kernelcore -= min(kernel_pages,
6518	required_kernelcore);
6519
6520	/* Continue if range is now fully accounted */
6521	if (end_pfn <= usable_startpfn) {
6522
6523	/*
6524	* Push zone_movable_pfn to the end so
6525	* that if we have to rebalance
6526	* kernelcore across nodes, we will
6527	* not double account here
6528	*/
6529	zone_movable_pfn[nid] = end_pfn;
6530	continue;
6531	}
6532	start_pfn = usable_startpfn;
6533	}
6534
6535	/*
6536	* The usable PFN range for ZONE_MOVABLE is from
6537	* start_pfn->end_pfn. Calculate size_pages as the
6538	* number of pages used as kernelcore
6539	*/
6540	size_pages = end_pfn - start_pfn;
6541	if (size_pages > kernelcore_remaining)
6542	size_pages = kernelcore_remaining;
6543	zone_movable_pfn[nid] = start_pfn + size_pages;
6544
6545	/*
6546	* Some kernelcore has been met, update counts and
6547	* break if the kernelcore for this node has been
6548	* satisfied
6549	*/
6550	required_kernelcore -= min(required_kernelcore,
6551	size_pages);
6552	kernelcore_remaining -= size_pages;
6553	if (!kernelcore_remaining)
6554	break;
6555	}
6556	}
6557
6558	/*
6559	* If there is still required_kernelcore, we do another pass with one
6560	* less node in the count. This will push zone_movable_pfn[nid] further
6561	* along on the nodes that still have memory until kernelcore is
6562	* satisfied
6563	*/
6564	usable_nodes--;
6565	if (usable_nodes && required_kernelcore > usable_nodes)
6566	goto restart;
6567
6568	out2:
6569	/* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
6570	for (nid = 0; nid < MAX_NUMNODES; nid++)
6571	zone_movable_pfn[nid] =
6572	roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES);
6573
6574	out:
6575	/* restore the node_state */
6576	node_states[N_MEMORY] = saved_node_state;
6577	}
6578
6579	/* Any regular or high memory on that node ? */
6580	static void check_for_memory(pg_data_t *pgdat, int nid)
6581	{
6582	enum zone_type zone_type;
6583
6584	if (N_MEMORY == N_NORMAL_MEMORY)
6585	return;
6586
6587	for (zone_type = 0; zone_type <= ZONE_MOVABLE - 1; zone_type++) {
6588	struct zone *zone = &pgdat->node_zones[zone_type];
6589	if (populated_zone(zone)) {
6590	node_set_state(nid, N_HIGH_MEMORY);
6591	if (N_NORMAL_MEMORY != N_HIGH_MEMORY &&
6592	zone_type <= ZONE_NORMAL)
6593	node_set_state(nid, N_NORMAL_MEMORY);
6594	break;
6595	}
6596	}
6597	}
6598
6599	/**
6600	* free_area_init_nodes - Initialise all pg_data_t and zone data
6601	* @max_zone_pfn: an array of max PFNs for each zone
6602	*
6603	* This will call free_area_init_node() for each active node in the system.
6604	* Using the page ranges provided by memblock_set_node(), the size of each
6605	* zone in each node and their holes is calculated. If the maximum PFN
6606	* between two adjacent zones match, it is assumed that the zone is empty.
6607	* For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
6608	* that arch_max_dma32_pfn has no pages. It is also assumed that a zone
6609	* starts where the previous one ended. For example, ZONE_DMA32 starts
6610	* at arch_max_dma_pfn.
6611	*/
6612	void __init free_area_init_nodes(unsigned long *max_zone_pfn)
6613	{
6614	unsigned long start_pfn, end_pfn;
6615	int i, nid;
6616
6617	/* Record where the zone boundaries are */
6618	memset(arch_zone_lowest_possible_pfn, 0,
6619	sizeof(arch_zone_lowest_possible_pfn));
6620	memset(arch_zone_highest_possible_pfn, 0,
6621	sizeof(arch_zone_highest_possible_pfn));
6622
6623	start_pfn = find_min_pfn_with_active_regions();
6624
6625	for (i = 0; i < MAX_NR_ZONES; i++) {
6626	if (i == ZONE_MOVABLE)
6627	continue;
6628
6629	end_pfn = max(max_zone_pfn[i], start_pfn);
6630	arch_zone_lowest_possible_pfn[i] = start_pfn;
6631	arch_zone_highest_possible_pfn[i] = end_pfn;
6632
6633	start_pfn = end_pfn;
6634	}
6635	arch_zone_lowest_possible_pfn[ZONE_MOVABLE] = 0;
6636	arch_zone_highest_possible_pfn[ZONE_MOVABLE] = 0;
6637
6638	/* Find the PFNs that ZONE_MOVABLE begins at in each node */
6639	memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn));
6640	find_zone_movable_pfns_for_nodes();
6641
6642	/* Print out the zone ranges */
6643	pr_info("Zone ranges:\n");
6644	for (i = 0; i < MAX_NR_ZONES; i++) {
6645	if (i == ZONE_MOVABLE)
6646	continue;
6647	pr_info(" %-8s ", zone_names[i]);
6648	if (arch_zone_lowest_possible_pfn[i] ==
6649	arch_zone_highest_possible_pfn[i])
6650	pr_cont("empty\n");
6651	else
6652	pr_cont("[mem %#018Lx-%#018Lx]\n",
6653	(u64)arch_zone_lowest_possible_pfn[i]
6654	<< PAGE_SHIFT,
6655	((u64)arch_zone_highest_possible_pfn[i]
6656	<< PAGE_SHIFT) - 1);
6657	}
6658
6659	/* Print out the PFNs ZONE_MOVABLE begins at in each node */
6660	pr_info("Movable zone start for each node\n");
6661	for (i = 0; i < MAX_NUMNODES; i++) {
6662	if (zone_movable_pfn[i])
6663	pr_info(" Node %d: %#018Lx\n", i,
6664	(u64)zone_movable_pfn[i] << PAGE_SHIFT);
6665	}
6666
6667	/* Print out the early node map */
6668	pr_info("Early memory node ranges\n");
6669	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid)
6670	pr_info(" node %3d: [mem %#018Lx-%#018Lx]\n", nid,
6671	(u64)start_pfn << PAGE_SHIFT,
6672	((u64)end_pfn << PAGE_SHIFT) - 1);
6673
6674	/* Initialise every node */
6675	mminit_verify_pageflags_layout();
6676	setup_nr_node_ids();
6677	for_each_online_node(nid) {
6678	pg_data_t *pgdat = NODE_DATA(nid);
6679	free_area_init_node(nid, NULL,
6680	find_min_pfn_for_node(nid), NULL);
6681
6682	/* Any memory on that node */
6683	if (pgdat->node_present_pages)
6684	node_set_state(nid, N_MEMORY);
6685	check_for_memory(pgdat, nid);
6686	}
6687	}
6688
6689	static int __init cmdline_parse_core(char *p, unsigned long *core)
6690	{
6691	unsigned long long coremem;
6692	if (!p)
6693	return -EINVAL;
6694
6695	coremem = memparse(p, &p);
6696	*core = coremem >> PAGE_SHIFT;
6697
6698	/* Paranoid check that UL is enough for the coremem value */
6699	WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX);
6700
6701	return 0;
6702	}
6703
6704	/*
6705	* kernelcore=size sets the amount of memory for use for allocations that
6706	* cannot be reclaimed or migrated.
6707	*/
6708	static int __init cmdline_parse_kernelcore(char *p)
6709	{
6710	/* parse kernelcore=mirror */
6711	if (parse_option_str(p, "mirror")) {
6712	mirrored_kernelcore = true;
6713	return 0;
6714	}
6715
6716	return cmdline_parse_core(p, &required_kernelcore);
6717	}
6718
6719	/*
6720	* movablecore=size sets the amount of memory for use for allocations that
6721	* can be reclaimed or migrated.
6722	*/
6723	static int __init cmdline_parse_movablecore(char *p)
6724	{
6725	return cmdline_parse_core(p, &required_movablecore);
6726	}
6727
6728	early_param("kernelcore", cmdline_parse_kernelcore);
6729	early_param("movablecore", cmdline_parse_movablecore);
6730
6731	#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
6732
6733	void adjust_managed_page_count(struct page *page, long count)
6734	{
6735	spin_lock(&managed_page_count_lock);
6736	page_zone(page)->managed_pages += count;
6737	totalram_pages += count;
6738	#ifdef CONFIG_HIGHMEM
6739	if (PageHighMem(page))
6740	totalhigh_pages += count;
6741	#endif
6742	spin_unlock(&managed_page_count_lock);
6743	}
6744	EXPORT_SYMBOL(adjust_managed_page_count);
6745
6746	unsigned long free_reserved_area(void *start, void *end, int poison, char *s)
6747	{
6748	void *pos;
6749	unsigned long pages = 0;
6750
6751	start = (void *)PAGE_ALIGN((unsigned long)start);
6752	end = (void *)((unsigned long)end & PAGE_MASK);
6753	for (pos = start; pos < end; pos += PAGE_SIZE, pages++) {
6754	if ((unsigned int)poison <= 0xFF)
6755	memset(pos, poison, PAGE_SIZE);
6756	free_reserved_page(virt_to_page(pos));
6757	}
6758
6759	if (pages && s)
6760	pr_info("Freeing %s memory: %ldK\n",
6761	s, pages << (PAGE_SHIFT - 10));
6762
6763	return pages;
6764	}
6765	EXPORT_SYMBOL(free_reserved_area);
6766
6767	#ifdef CONFIG_HIGHMEM
6768	void free_highmem_page(struct page *page)
6769	{
6770	__free_reserved_page(page);
6771	totalram_pages++;
6772	page_zone(page)->managed_pages++;
6773	totalhigh_pages++;
6774	}
6775	#endif
6776
6777
6778	void __init mem_init_print_info(const char *str)
6779	{
6780	unsigned long physpages, codesize, datasize, rosize, bss_size;
6781	unsigned long init_code_size, init_data_size;
6782
6783	physpages = get_num_physpages();
6784	codesize = _etext - _stext;
6785	datasize = _edata - _sdata;
6786	rosize = __end_rodata - __start_rodata;
6787	bss_size = __bss_stop - __bss_start;
6788	init_data_size = __init_end - __init_begin;
6789	init_code_size = _einittext - _sinittext;
6790
6791	/*
6792	* Detect special cases and adjust section sizes accordingly:
6793	* 1) .init.* may be embedded into .data sections
6794	* 2) .init.text.* may be out of [__init_begin, __init_end],
6795	* please refer to arch/tile/kernel/vmlinux.lds.S.
6796	* 3) .rodata.* may be embedded into .text or .data sections.
6797	*/
6798	#define adj_init_size(start, end, size, pos, adj) \
6799	do { \
6800	if (start <= pos && pos < end && size > adj) \
6801	size -= adj; \
6802	} while (0)
6803
6804	adj_init_size(__init_begin, __init_end, init_data_size,
6805	_sinittext, init_code_size);
6806	adj_init_size(_stext, _etext, codesize, _sinittext, init_code_size);
6807	adj_init_size(_sdata, _edata, datasize, __init_begin, init_data_size);
6808	adj_init_size(_stext, _etext, codesize, __start_rodata, rosize);
6809	adj_init_size(_sdata, _edata, datasize, __start_rodata, rosize);
6810
6811	#undef adj_init_size
6812
6813	pr_info("Memory: %luK/%luK available (%luK kernel code, %luK rwdata, %luK rodata, %luK init, %luK bss, %luK reserved, %luK cma-reserved"
6814	#ifdef CONFIG_HIGHMEM
6815	", %luK highmem"
6816	#endif
6817	"%s%s)\n",
6818	nr_free_pages() << (PAGE_SHIFT - 10),
6819	physpages << (PAGE_SHIFT - 10),
6820	codesize >> 10, datasize >> 10, rosize >> 10,
6821	(init_data_size + init_code_size) >> 10, bss_size >> 10,
6822	(physpages - totalram_pages - totalcma_pages) << (PAGE_SHIFT - 10),
6823	totalcma_pages << (PAGE_SHIFT - 10),
6824	#ifdef CONFIG_HIGHMEM
6825	totalhigh_pages << (PAGE_SHIFT - 10),
6826	#endif
6827	str ? ", " : "", str ? str : "");
6828	}
6829
6830	/**
6831	* set_dma_reserve - set the specified number of pages reserved in the first zone
6832	* @new_dma_reserve: The number of pages to mark reserved
6833	*
6834	* The per-cpu batchsize and zone watermarks are determined by managed_pages.
6835	* In the DMA zone, a significant percentage may be consumed by kernel image
6836	* and other unfreeable allocations which can skew the watermarks badly. This
6837	* function may optionally be used to account for unfreeable pages in the
6838	* first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
6839	* smaller per-cpu batchsize.
6840	*/
6841	void __init set_dma_reserve(unsigned long new_dma_reserve)
6842	{
6843	dma_reserve = new_dma_reserve;
6844	}
6845
6846	void __init free_area_init(unsigned long *zones_size)
6847	{
6848	free_area_init_node(0, zones_size,
6849	__pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL);
6850	}
6851
6852	static int page_alloc_cpu_notify(struct notifier_block *self,
6853	unsigned long action, void *hcpu)
6854	{
6855	int cpu = (unsigned long)hcpu;
6856
6857	if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
6858	lru_add_drain_cpu(cpu);
6859	drain_pages(cpu);
6860
6861	/*
6862	* Spill the event counters of the dead processor
6863	* into the current processors event counters.
6864	* This artificially elevates the count of the current
6865	* processor.
6866	*/
6867	vm_events_fold_cpu(cpu);
6868
6869	/*
6870	* Zero the differential counters of the dead processor
6871	* so that the vm statistics are consistent.
6872	*
6873	* This is only okay since the processor is dead and cannot
6874	* race with what we are doing.
6875	*/
6876	cpu_vm_stats_fold(cpu);
6877	}
6878	return NOTIFY_OK;
6879	}
6880
6881	void __init page_alloc_init(void)
6882	{
6883	hotcpu_notifier(page_alloc_cpu_notify, 0);
6884	}
6885
6886	/*
6887	* calculate_totalreserve_pages - called when sysctl_lowmem_reserve_ratio
6888	* or min_free_kbytes changes.
6889	*/
6890	static void calculate_totalreserve_pages(void)
6891	{
6892	struct pglist_data *pgdat;
6893	unsigned long reserve_pages = 0;
6894	enum zone_type i, j;
6895
6896	for_each_online_pgdat(pgdat) {
6897
6898	pgdat->totalreserve_pages = 0;
6899
6900	for (i = 0; i < MAX_NR_ZONES; i++) {
6901	struct zone *zone = pgdat->node_zones + i;
6902	long max = 0;
6903
6904	/* Find valid and maximum lowmem_reserve in the zone */
6905	for (j = i; j < MAX_NR_ZONES; j++) {
6906	if (zone->lowmem_reserve[j] > max)
6907	max = zone->lowmem_reserve[j];
6908	}
6909
6910	/* we treat the high watermark as reserved pages. */
6911	max += high_wmark_pages(zone);
6912
6913	if (max > zone->managed_pages)
6914	max = zone->managed_pages;
6915
6916	pgdat->totalreserve_pages += max;
6917
6918	reserve_pages += max;
6919	}
6920	}
6921	totalreserve_pages = reserve_pages;
6922	}
6923
6924	/*
6925	* setup_per_zone_lowmem_reserve - called whenever
6926	* sysctl_lowmem_reserve_ratio changes. Ensures that each zone
6927	* has a correct pages reserved value, so an adequate number of
6928	* pages are left in the zone after a successful __alloc_pages().
6929	*/
6930	static void setup_per_zone_lowmem_reserve(void)
6931	{
6932	struct pglist_data *pgdat;
6933	enum zone_type j, idx;
6934
6935	for_each_online_pgdat(pgdat) {
6936	for (j = 0; j < MAX_NR_ZONES; j++) {
6937	struct zone *zone = pgdat->node_zones + j;
6938	unsigned long managed_pages = zone->managed_pages;
6939
6940	zone->lowmem_reserve[j] = 0;
6941
6942	idx = j;
6943	while (idx) {
6944	struct zone *lower_zone;
6945
6946	idx--;
6947
6948	if (sysctl_lowmem_reserve_ratio[idx] < 1)
6949	sysctl_lowmem_reserve_ratio[idx] = 1;
6950
6951	lower_zone = pgdat->node_zones + idx;
6952	lower_zone->lowmem_reserve[j] = managed_pages /
6953	sysctl_lowmem_reserve_ratio[idx];
6954	managed_pages += lower_zone->managed_pages;
6955	}
6956	}
6957	}
6958
6959	/* update totalreserve_pages */
6960	calculate_totalreserve_pages();
6961	}
6962
6963	static void __setup_per_zone_wmarks(void)
6964	{
6965	unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10);
6966	unsigned long pages_low = extra_free_kbytes >> (PAGE_SHIFT - 10);
6967	unsigned long lowmem_pages = 0;
6968	struct zone *zone;
6969	unsigned long flags;
6970
6971	/* Calculate total number of !ZONE_HIGHMEM pages */
6972	for_each_zone(zone) {
6973	if (!is_highmem(zone))
6974	lowmem_pages += zone->managed_pages;
6975	}
6976
6977	for_each_zone(zone) {
6978	u64 min, low;
6979
6980	spin_lock_irqsave(&zone->lock, flags);
6981	min = (u64)pages_min * zone->managed_pages;
6982	do_div(min, lowmem_pages);
6983	low = (u64)pages_low * zone->managed_pages;
6984	do_div(low, vm_total_pages);
6985
6986	if (is_highmem(zone)) {
6987	/*
6988	* __GFP_HIGH and PF_MEMALLOC allocations usually don't
6989	* need highmem pages, so cap pages_min to a small
6990	* value here.
6991	*
6992	* The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
6993	* deltas control asynch page reclaim, and so should
6994	* not be capped for highmem.
6995	*/
6996	unsigned long min_pages;
6997
6998	min_pages = zone->managed_pages / 1024;
6999	min_pages = clamp(min_pages, SWAP_CLUSTER_MAX, 128UL);
7000	zone->watermark[WMARK_MIN] = min_pages;
7001	} else {
7002	/*
7003	* If it's a lowmem zone, reserve a number of pages
7004	* proportionate to the zone's size.
7005	*/
7006	zone->watermark[WMARK_MIN] = min;
7007	}
7008
7009	/*
7010	* Set the kswapd watermarks distance according to the
7011	* scale factor in proportion to available memory, but
7012	* ensure a minimum size on small systems.
7013	*/
7014	min = max_t(u64, min >> 2,
7015	mult_frac(zone->managed_pages,
7016	watermark_scale_factor, 10000));
7017
7018	zone->watermark[WMARK_LOW] = min_wmark_pages(zone) +
7019	low + min;
7020	zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) +
7021	low + min * 2;
7022
7023	spin_unlock_irqrestore(&zone->lock, flags);
7024	}
7025
7026	/* update totalreserve_pages */
7027	calculate_totalreserve_pages();
7028	}
7029
7030	/**
7031	* setup_per_zone_wmarks - called when min_free_kbytes changes
7032	* or when memory is hot-{added|removed}
7033	*
7034	* Ensures that the watermark[min,low,high] values for each zone are set
7035	* correctly with respect to min_free_kbytes.
7036	*/
7037	void setup_per_zone_wmarks(void)
7038	{
7039	mutex_lock(&zonelists_mutex);
7040	__setup_per_zone_wmarks();
7041	mutex_unlock(&zonelists_mutex);
7042	}
7043
7044	/*
7045	* Initialise min_free_kbytes.
7046	*
7047	* For small machines we want it small (128k min). For large machines
7048	* we want it large (64MB max). But it is not linear, because network
7049	* bandwidth does not increase linearly with machine size. We use
7050	*
7051	* min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
7052	* min_free_kbytes = sqrt(lowmem_kbytes * 16)
7053	*
7054	* which yields
7055	*
7056	* 16MB: 512k
7057	* 32MB: 724k
7058	* 64MB: 1024k
7059	* 128MB: 1448k
7060	* 256MB: 2048k
7061	* 512MB: 2896k
7062	* 1024MB: 4096k
7063	* 2048MB: 5792k
7064	* 4096MB: 8192k
7065	* 8192MB: 11584k
7066	* 16384MB: 16384k
7067	*/
7068	int __meminit init_per_zone_wmark_min(void)
7069	{
7070	unsigned long lowmem_kbytes;
7071	int new_min_free_kbytes;
7072
7073	lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10);
7074	new_min_free_kbytes = int_sqrt(lowmem_kbytes * 16);
7075
7076	if (new_min_free_kbytes > user_min_free_kbytes) {
7077	min_free_kbytes = new_min_free_kbytes;
7078	if (min_free_kbytes < 128)
7079	min_free_kbytes = 128;
7080	if (min_free_kbytes > 65536)
7081	min_free_kbytes = 65536;
7082	} else {
7083	pr_warn("min_free_kbytes is not updated to %d because user defined value %d is preferred\n",
7084	new_min_free_kbytes, user_min_free_kbytes);
7085	}
7086	setup_per_zone_wmarks();
7087	refresh_zone_stat_thresholds();
7088	setup_per_zone_lowmem_reserve();
7089
7090	#ifdef CONFIG_NUMA
7091	setup_min_unmapped_ratio();
7092	setup_min_slab_ratio();
7093	#endif
7094
7095	return 0;
7096	}
7097	core_initcall(init_per_zone_wmark_min)
7098
7099	/*
7100	* min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
7101	* that we can call two helper functions whenever min_free_kbytes
7102	* or extra_free_kbytes changes.
7103	*/
7104	int min_free_kbytes_sysctl_handler(struct ctl_table *table, int write,
7105	void __user *buffer, size_t *length, loff_t *ppos)
7106	{
7107	int rc;
7108
7109	rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
7110	if (rc)
7111	return rc;
7112
7113	if (write) {
7114	user_min_free_kbytes = min_free_kbytes;
7115	setup_per_zone_wmarks();
7116	}
7117	return 0;
7118	}
7119
7120	int watermark_scale_factor_sysctl_handler(struct ctl_table *table, int write,
7121	void __user *buffer, size_t *length, loff_t *ppos)
7122	{
7123	int rc;
7124
7125	rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
7126	if (rc)
7127	return rc;
7128
7129	if (write)
7130	setup_per_zone_wmarks();
7131
7132	return 0;
7133	}
7134
7135	#ifdef CONFIG_NUMA
7136	static void setup_min_unmapped_ratio(void)
7137	{
7138	pg_data_t *pgdat;
7139	struct zone *zone;
7140
7141	for_each_online_pgdat(pgdat)
7142	pgdat->min_unmapped_pages = 0;
7143
7144	for_each_zone(zone)
7145	zone->zone_pgdat->min_unmapped_pages += (zone->managed_pages *
7146	sysctl_min_unmapped_ratio) / 100;
7147	}
7148
7149
7150	int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *table, int write,
7151	void __user *buffer, size_t *length, loff_t *ppos)
7152	{
7153	int rc;
7154
7155	rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
7156	if (rc)
7157	return rc;
7158
7159	setup_min_unmapped_ratio();
7160
7161	return 0;
7162	}
7163
7164	static void setup_min_slab_ratio(void)
7165	{
7166	pg_data_t *pgdat;
7167	struct zone *zone;
7168
7169	for_each_online_pgdat(pgdat)
7170	pgdat->min_slab_pages = 0;
7171
7172	for_each_zone(zone)
7173	zone->zone_pgdat->min_slab_pages += (zone->managed_pages *
7174	sysctl_min_slab_ratio) / 100;
7175	}
7176
7177	int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *table, int write,
7178	void __user *buffer, size_t *length, loff_t *ppos)
7179	{
7180	int rc;
7181
7182	rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
7183	if (rc)
7184	return rc;
7185
7186	setup_min_slab_ratio();
7187
7188	return 0;
7189	}
7190	#endif
7191
7192	/*
7193	* lowmem_reserve_ratio_sysctl_handler - just a wrapper around
7194	* proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
7195	* whenever sysctl_lowmem_reserve_ratio changes.
7196	*
7197	* The reserve ratio obviously has absolutely no relation with the
7198	* minimum watermarks. The lowmem reserve ratio can only make sense
7199	* if in function of the boot time zone sizes.
7200	*/
7201	int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *table, int write,
7202	void __user *buffer, size_t *length, loff_t *ppos)
7203	{
7204	proc_dointvec_minmax(table, write, buffer, length, ppos);
7205	setup_per_zone_lowmem_reserve();
7206	return 0;
7207	}
7208
7209	/*
7210	* percpu_pagelist_fraction - changes the pcp->high for each zone on each
7211	* cpu. It is the fraction of total pages in each zone that a hot per cpu
7212	* pagelist can have before it gets flushed back to buddy allocator.
7213	*/
7214	int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *table, int write,
7215	void __user *buffer, size_t *length, loff_t *ppos)
7216	{
7217	struct zone *zone;
7218	int old_percpu_pagelist_fraction;
7219	int ret;
7220
7221	mutex_lock(&pcp_batch_high_lock);
7222	old_percpu_pagelist_fraction = percpu_pagelist_fraction;
7223
7224	ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
7225	if (!write || ret < 0)
7226	goto out;
7227
7228	/* Sanity checking to avoid pcp imbalance */
7229	if (percpu_pagelist_fraction &&
7230	percpu_pagelist_fraction < MIN_PERCPU_PAGELIST_FRACTION) {
7231	percpu_pagelist_fraction = old_percpu_pagelist_fraction;
7232	ret = -EINVAL;
7233	goto out;
7234	}
7235
7236	/* No change? */
7237	if (percpu_pagelist_fraction == old_percpu_pagelist_fraction)
7238	goto out;
7239
7240	for_each_populated_zone(zone) {
7241	unsigned int cpu;
7242
7243	for_each_possible_cpu(cpu)
7244	pageset_set_high_and_batch(zone,
7245	per_cpu_ptr(zone->pageset, cpu));
7246	}
7247	out:
7248	mutex_unlock(&pcp_batch_high_lock);
7249	return ret;
7250	}
7251
7252	#ifdef CONFIG_NUMA
7253	int hashdist = HASHDIST_DEFAULT;
7254
7255	static int __init set_hashdist(char *str)
7256	{
7257	if (!str)
7258	return 0;
7259	hashdist = simple_strtoul(str, &str, 0);
7260	return 1;
7261	}
7262	__setup("hashdist=", set_hashdist);
7263	#endif
7264
7265	#ifndef __HAVE_ARCH_RESERVED_KERNEL_PAGES
7266	/*
7267	* Returns the number of pages that arch has reserved but
7268	* is not known to alloc_large_system_hash().
7269	*/
7270	static unsigned long __init arch_reserved_kernel_pages(void)
7271	{
7272	return 0;
7273	}
7274	#endif
7275
7276	/*
7277	* allocate a large system hash table from bootmem
7278	* - it is assumed that the hash table must contain an exact power-of-2
7279	* quantity of entries
7280	* - limit is the number of hash buckets, not the total allocation size
7281	*/
7282	void *__init alloc_large_system_hash(const char *tablename,
7283	unsigned long bucketsize,
7284	unsigned long numentries,
7285	int scale,
7286	int flags,
7287	unsigned int *_hash_shift,
7288	unsigned int *_hash_mask,
7289	unsigned long low_limit,
7290	unsigned long high_limit)
7291	{
7292	unsigned long long max = high_limit;
7293	unsigned long log2qty, size;
7294	void *table = NULL;
7295
7296	/* allow the kernel cmdline to have a say */
7297	if (!numentries) {
7298	/* round applicable memory size up to nearest megabyte */
7299	numentries = nr_kernel_pages;
7300	numentries -= arch_reserved_kernel_pages();
7301
7302	/* It isn't necessary when PAGE_SIZE >= 1MB */
7303	if (PAGE_SHIFT < 20)
7304	numentries = round_up(numentries, (1<<20)/PAGE_SIZE);
7305
7306	/* limit to 1 bucket per 2^scale bytes of low memory */
7307	if (scale > PAGE_SHIFT)
7308	numentries >>= (scale - PAGE_SHIFT);
7309	else
7310	numentries <<= (PAGE_SHIFT - scale);
7311
7312	/* Make sure we've got at least a 0-order allocation.. */
7313	if (unlikely(flags & HASH_SMALL)) {
7314	/* Makes no sense without HASH_EARLY */
7315	WARN_ON(!(flags & HASH_EARLY));
7316	if (!(numentries >> *_hash_shift)) {
7317	numentries = 1UL << *_hash_shift;
7318	BUG_ON(!numentries);
7319	}
7320	} else if (unlikely((numentries * bucketsize) < PAGE_SIZE))
7321	numentries = PAGE_SIZE / bucketsize;
7322	}
7323	numentries = roundup_pow_of_two(numentries);
7324
7325	/* limit allocation size to 1/16 total memory by default */
7326	if (max == 0) {
7327	max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4;
7328	do_div(max, bucketsize);
7329	}
7330	max = min(max, 0x80000000ULL);
7331
7332	if (numentries < low_limit)
7333	numentries = low_limit;
7334	if (numentries > max)
7335	numentries = max;
7336
7337	log2qty = ilog2(numentries);
7338
7339	do {
7340	size = bucketsize << log2qty;
7341	if (flags & HASH_EARLY)
7342	table = memblock_virt_alloc_nopanic(size, 0);
7343	else if (hashdist)
7344	table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL);
7345	else {
7346	/*
7347	* If bucketsize is not a power-of-two, we may free
7348	* some pages at the end of hash table which
7349	* alloc_pages_exact() automatically does
7350	*/
7351	if (get_order(size) < MAX_ORDER) {
7352	table = alloc_pages_exact(size, GFP_ATOMIC);
7353	kmemleak_alloc(table, size, 1, GFP_ATOMIC);
7354	}
7355	}
7356	} while (!table && size > PAGE_SIZE && --log2qty);
7357
7358	if (!table)
7359	panic("Failed to allocate %s hash table\n", tablename);
7360
7361	pr_info("%s hash table entries: %ld (order: %d, %lu bytes)\n",
7362	tablename, 1UL << log2qty, ilog2(size) - PAGE_SHIFT, size);
7363
7364	if (_hash_shift)
7365	*_hash_shift = log2qty;
7366	if (_hash_mask)
7367	*_hash_mask = (1 << log2qty) - 1;
7368
7369	return table;
7370	}
7371
7372	/*
7373	* This function checks whether pageblock includes unmovable pages or not.
7374	* If @count is not zero, it is okay to include less @count unmovable pages
7375	*
7376	* PageLRU check without isolation or lru_lock could race so that
7377	* MIGRATE_MOVABLE block might include unmovable pages. It means you can't
7378	* expect this function should be exact.
7379	*/
7380	bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
7381	bool skip_hwpoisoned_pages)
7382	{
7383	unsigned long pfn, iter, found;
7384	int mt;
7385
7386	/*
7387	* For avoiding noise data, lru_add_drain_all() should be called
7388	* If ZONE_MOVABLE, the zone never contains unmovable pages
7389	*/
7390	if (zone_idx(zone) == ZONE_MOVABLE)
7391	return false;
7392	mt = get_pageblock_migratetype(page);
7393	if (mt == MIGRATE_MOVABLE || is_migrate_cma(mt))
7394	return false;
7395
7396	pfn = page_to_pfn(page);
7397	for (found = 0, iter = 0; iter < pageblock_nr_pages; iter++) {
7398	unsigned long check = pfn + iter;
7399
7400	if (!pfn_valid_within(check))
7401	continue;
7402
7403	page = pfn_to_page(check);
7404
7405	/*
7406	* Hugepages are not in LRU lists, but they're movable.
7407	* We need not scan over tail pages bacause we don't
7408	* handle each tail page individually in migration.
7409	*/
7410	if (PageHuge(page)) {
7411	iter = round_up(iter + 1, 1<<compound_order(page)) - 1;
7412	continue;
7413	}
7414
7415	/*
7416	* We can't use page_count without pin a page
7417	* because another CPU can free compound page.
7418	* This check already skips compound tails of THP
7419	* because their page->_refcount is zero at all time.
7420	*/
7421	if (!page_ref_count(page)) {
7422	if (PageBuddy(page))
7423	iter += (1 << page_order(page)) - 1;
7424	continue;
7425	}
7426
7427	/*
7428	* The HWPoisoned page may be not in buddy system, and
7429	* page_count() is not 0.
7430	*/
7431	if (skip_hwpoisoned_pages && PageHWPoison(page))
7432	continue;
7433
7434	if (!PageLRU(page))
7435	found++;
7436	/*
7437	* If there are RECLAIMABLE pages, we need to check
7438	* it. But now, memory offline itself doesn't call
7439	* shrink_node_slabs() and it still to be fixed.
7440	*/
7441	/*
7442	* If the page is not RAM, page_count()should be 0.
7443	* we don't need more check. This is an _used_ not-movable page.
7444	*
7445	* The problematic thing here is PG_reserved pages. PG_reserved
7446	* is set to both of a memory hole page and a _used_ kernel
7447	* page at boot.
7448	*/
7449	if (found > count)
7450	return true;
7451	}
7452	return false;
7453	}
7454
7455	bool is_pageblock_removable_nolock(struct page *page)
7456	{
7457	struct zone *zone;
7458	unsigned long pfn;
7459
7460	/*
7461	* We have to be careful here because we are iterating over memory
7462	* sections which are not zone aware so we might end up outside of
7463	* the zone but still within the section.
7464	* We have to take care about the node as well. If the node is offline
7465	* its NODE_DATA will be NULL - see page_zone.
7466	*/
7467	if (!node_online(page_to_nid(page)))
7468	return false;
7469
7470	zone = page_zone(page);
7471	pfn = page_to_pfn(page);
7472	if (!zone_spans_pfn(zone, pfn))
7473	return false;
7474
7475	return !has_unmovable_pages(zone, page, 0, true);
7476	}
7477
7478	#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
7479
7480	static unsigned long pfn_max_align_down(unsigned long pfn)
7481	{
7482	return pfn & ~(max_t(unsigned long, MAX_ORDER_NR_PAGES,
7483	pageblock_nr_pages) - 1);
7484	}
7485
7486	static unsigned long pfn_max_align_up(unsigned long pfn)
7487	{
7488	return ALIGN(pfn, max_t(unsigned long, MAX_ORDER_NR_PAGES,
7489	pageblock_nr_pages));
7490	}
7491
7492	/* [start, end) must belong to a single zone. */
7493	static int __alloc_contig_migrate_range(struct compact_control *cc,
7494	unsigned long start, unsigned long end)
7495	{
7496	/* This function is based on compact_zone() from compaction.c. */
7497	unsigned long nr_reclaimed;
7498	unsigned long pfn = start;
7499	unsigned int tries = 0;
7500	int ret = 0;
7501
7502	migrate_prep();
7503
7504	while (pfn < end || !list_empty(&cc->migratepages)) {
7505	if (fatal_signal_pending(current)) {
7506	ret = -EINTR;
7507	break;
7508	}
7509
7510	if (list_empty(&cc->migratepages)) {
7511	cc->nr_migratepages = 0;
7512	pfn = isolate_migratepages_range(cc, pfn, end);
7513	if (!pfn) {
7514	ret = -EINTR;
7515	break;
7516	}
7517	tries = 0;
7518	} else if (++tries == 5) {
7519	ret = ret < 0 ? ret : -EBUSY;
7520	break;
7521	}
7522
7523	nr_reclaimed = reclaim_clean_pages_from_list(cc->zone,
7524	&cc->migratepages);
7525	cc->nr_migratepages -= nr_reclaimed;
7526
7527	ret = migrate_pages(&cc->migratepages, alloc_migrate_target,
7528	NULL, 0, cc->mode, MR_CMA);
7529	}
7530	if (ret < 0) {
7531	putback_movable_pages(&cc->migratepages);
7532	return ret;
7533	}
7534	return 0;
7535	}
7536
7537	/**
7538	* alloc_contig_range() -- tries to allocate given range of pages
7539	* @start: start PFN to allocate
7540	* @end: one-past-the-last PFN to allocate
7541	* @migratetype: migratetype of the underlaying pageblocks (either
7542	* #MIGRATE_MOVABLE or #MIGRATE_CMA). All pageblocks
7543	* in range must have the same migratetype and it must
7544	* be either of the two.
7545	*
7546	* The PFN range does not have to be pageblock or MAX_ORDER_NR_PAGES
7547	* aligned, however it's the caller's responsibility to guarantee that
7548	* we are the only thread that changes migrate type of pageblocks the
7549	* pages fall in.
7550	*
7551	* The PFN range must belong to a single zone.
7552	*
7553	* Returns zero on success or negative error code. On success all
7554	* pages which PFN is in [start, end) are allocated for the caller and
7555	* need to be freed with free_contig_range().
7556	*/
7557	int alloc_contig_range(unsigned long start, unsigned long end,
7558	unsigned migratetype)
7559	{
7560	unsigned long outer_start, outer_end;
7561	unsigned int order;
7562	int ret = 0;
7563
7564	struct compact_control cc = {
7565	.nr_migratepages = 0,
7566	.order = -1,
7567	.zone = page_zone(pfn_to_page(start)),
7568	.mode = MIGRATE_SYNC,
7569	.ignore_skip_hint = true,
7570	};
7571	INIT_LIST_HEAD(&cc.migratepages);
7572
7573	/*
7574	* What we do here is we mark all pageblocks in range as
7575	* MIGRATE_ISOLATE. Because pageblock and max order pages may
7576	* have different sizes, and due to the way page allocator
7577	* work, we align the range to biggest of the two pages so
7578	* that page allocator won't try to merge buddies from
7579	* different pageblocks and change MIGRATE_ISOLATE to some
7580	* other migration type.
7581	*
7582	* Once the pageblocks are marked as MIGRATE_ISOLATE, we
7583	* migrate the pages from an unaligned range (ie. pages that
7584	* we are interested in). This will put all the pages in
7585	* range back to page allocator as MIGRATE_ISOLATE.
7586	*
7587	* When this is done, we take the pages in range from page
7588	* allocator removing them from the buddy system. This way
7589	* page allocator will never consider using them.
7590	*
7591	* This lets us mark the pageblocks back as
7592	* MIGRATE_CMA/MIGRATE_MOVABLE so that free pages in the
7593	* aligned range but not in the unaligned, original range are
7594	* put back to page allocator so that buddy can use them.
7595	*/
7596
7597	ret = start_isolate_page_range(pfn_max_align_down(start),
7598	pfn_max_align_up(end), migratetype,
7599	false);
7600	if (ret)
7601	return ret;
7602
7603	/*
7604	* In case of -EBUSY, we'd like to know which page causes problem.
7605	* So, just fall through. test_pages_isolated() has a tracepoint
7606	* which will report the busy page.
7607	*
7608	* It is possible that busy pages could become available before
7609	* the call to test_pages_isolated, and the range will actually be
7610	* allocated. So, if we fall through be sure to clear ret so that
7611	* -EBUSY is not accidentally used or returned to caller.
7612	*/
7613	ret = __alloc_contig_migrate_range(&cc, start, end);
7614	if (ret && ret != -EBUSY)
7615	goto done;
7616	ret =0;
7617
7618	/*
7619	* Pages from [start, end) are within a MAX_ORDER_NR_PAGES
7620	* aligned blocks that are marked as MIGRATE_ISOLATE. What's
7621	* more, all pages in [start, end) are free in page allocator.
7622	* What we are going to do is to allocate all pages from
7623	* [start, end) (that is remove them from page allocator).
7624	*
7625	* The only problem is that pages at the beginning and at the
7626	* end of interesting range may be not aligned with pages that
7627	* page allocator holds, ie. they can be part of higher order
7628	* pages. Because of this, we reserve the bigger range and
7629	* once this is done free the pages we are not interested in.
7630	*
7631	* We don't have to hold zone->lock here because the pages are
7632	* isolated thus they won't get removed from buddy.
7633	*/
7634
7635	lru_add_drain_all();
7636	drain_all_pages(cc.zone);
7637
7638	order = 0;
7639	outer_start = start;
7640	while (!PageBuddy(pfn_to_page(outer_start))) {
7641	if (++order >= MAX_ORDER) {
7642	outer_start = start;
7643	break;
7644	}
7645	outer_start &= ~0UL << order;
7646	}
7647
7648	if (outer_start != start) {
7649	order = page_order(pfn_to_page(outer_start));
7650
7651	/*
7652	* outer_start page could be small order buddy page and
7653	* it doesn't include start page. Adjust outer_start
7654	* in this case to report failed page properly
7655	* on tracepoint in test_pages_isolated()
7656	*/
7657	if (outer_start + (1UL << order) <= start)
7658	outer_start = start;
7659	}
7660
7661	/* Make sure the range is really isolated. */
7662	if (test_pages_isolated(outer_start, end, false)) {
7663	pr_info_ratelimited("%s: [%lx, %lx) PFNs busy\n",
7664	__func__, outer_start, end);
7665	ret = -EBUSY;
7666	goto done;
7667	}
7668
7669	/* Grab isolated pages from freelists. */
7670	outer_end = isolate_freepages_range(&cc, outer_start, end);
7671	if (!outer_end) {
7672	ret = -EBUSY;
7673	goto done;
7674	}
7675
7676	/* Free head and tail (if any) */
7677	if (start != outer_start)
7678	free_contig_range(outer_start, start - outer_start);
7679	if (end != outer_end)
7680	free_contig_range(end, outer_end - end);
7681
7682	done:
7683	undo_isolate_page_range(pfn_max_align_down(start),
7684	pfn_max_align_up(end), migratetype);
7685	return ret;
7686	}
7687
7688	void free_contig_range(unsigned long pfn, unsigned nr_pages)
7689	{
7690	unsigned int count = 0;
7691
7692	for (; nr_pages--; pfn++) {
7693	struct page *page = pfn_to_page(pfn);
7694
7695	count += page_count(page) != 1;
7696	__free_page(page);
7697	}
7698	WARN(count != 0, "%d pages are still in use!\n", count);
7699	}
7700	#endif
7701
7702	#ifdef CONFIG_MEMORY_HOTPLUG
7703	/*
7704	* The zone indicated has a new number of managed_pages; batch sizes and percpu
7705	* page high values need to be recalulated.
7706	*/
7707	void __meminit zone_pcp_update(struct zone *zone)
7708	{
7709	unsigned cpu;
7710	mutex_lock(&pcp_batch_high_lock);
7711	for_each_possible_cpu(cpu)
7712	pageset_set_high_and_batch(zone,
7713	per_cpu_ptr(zone->pageset, cpu));
7714	mutex_unlock(&pcp_batch_high_lock);
7715	}
7716	#endif
7717
7718	void zone_pcp_reset(struct zone *zone)
7719	{
7720	unsigned long flags;
7721	int cpu;
7722	struct per_cpu_pageset *pset;
7723
7724	/* avoid races with drain_pages() */
7725	local_irq_save(flags);
7726	if (zone->pageset != &boot_pageset) {
7727	for_each_online_cpu(cpu) {
7728	pset = per_cpu_ptr(zone->pageset, cpu);
7729	drain_zonestat(zone, pset);
7730	}
7731	free_percpu(zone->pageset);
7732	zone->pageset = &boot_pageset;
7733	}
7734	local_irq_restore(flags);
7735	}
7736
7737	#ifdef CONFIG_MEMORY_HOTREMOVE
7738	/*
7739	* All pages in the range must be in a single zone and isolated
7740	* before calling this.
7741	*/
7742	void
7743	__offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
7744	{
7745	struct page *page;
7746	struct zone *zone;
7747	unsigned int order, i;
7748	unsigned long pfn;
7749	unsigned long flags;
7750	/* find the first valid pfn */
7751	for (pfn = start_pfn; pfn < end_pfn; pfn++)
7752	if (pfn_valid(pfn))
7753	break;
7754	if (pfn == end_pfn)
7755	return;
7756	zone = page_zone(pfn_to_page(pfn));
7757	spin_lock_irqsave(&zone->lock, flags);
7758	pfn = start_pfn;
7759	while (pfn < end_pfn) {
7760	if (!pfn_valid(pfn)) {
7761	pfn++;
7762	continue;
7763	}
7764	page = pfn_to_page(pfn);
7765	/*
7766	* The HWPoisoned page may be not in buddy system, and
7767	* page_count() is not 0.
7768	*/
7769	if (unlikely(!PageBuddy(page) && PageHWPoison(page))) {
7770	pfn++;
7771	SetPageReserved(page);
7772	continue;
7773	}
7774
7775	BUG_ON(page_count(page));
7776	BUG_ON(!PageBuddy(page));
7777	order = page_order(page);
7778	#ifdef CONFIG_DEBUG_VM
7779	pr_info("remove from free list %lx %d %lx\n",
7780	pfn, 1 << order, end_pfn);
7781	#endif
7782	list_del(&page->lru);
7783	rmv_page_order(page);
7784	zone->free_area[order].nr_free--;
7785	#ifdef CONFIG_AMLOGIC_MEMORY_EXTEND
7786	__mod_zone_migrate_state(zone, -(1 << order),
7787	get_pcppage_migratetype(page));
7788	#endif /* CONFIG_AMLOGIC_MEMORY_EXTEND */
7789	for (i = 0; i < (1 << order); i++)
7790	SetPageReserved((page+i));
7791	pfn += (1 << order);
7792	}
7793	spin_unlock_irqrestore(&zone->lock, flags);
7794	}
7795	#endif
7796
7797	bool is_free_buddy_page(struct page *page)
7798	{
7799	struct zone *zone = page_zone(page);
7800	unsigned long pfn = page_to_pfn(page);
7801	unsigned long flags;
7802	unsigned int order;
7803
7804	spin_lock_irqsave(&zone->lock, flags);
7805	for (order = 0; order < MAX_ORDER; order++) {
7806	struct page *page_head = page - (pfn & ((1 << order) - 1));
7807
7808	if (PageBuddy(page_head) && page_order(page_head) >= order)
7809	break;
7810	}
7811	spin_unlock_irqrestore(&zone->lock, flags);
7812
7813	return order < MAX_ORDER;
7814	}
7815