xref: /linux/mm/mm_init.c (revision e6a901a00822659181c93c86d8bbc2a17779fddc)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * mm_init.c - Memory initialisation verification and debugging
4  *
5  * Copyright 2008 IBM Corporation, 2008
6  * Author Mel Gorman <mel@csn.ul.ie>
7  *
8  */
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <linux/kobject.h>
12 #include <linux/export.h>
13 #include <linux/memory.h>
14 #include <linux/notifier.h>
15 #include <linux/sched.h>
16 #include <linux/mman.h>
17 #include <linux/memblock.h>
18 #include <linux/page-isolation.h>
19 #include <linux/padata.h>
20 #include <linux/nmi.h>
21 #include <linux/buffer_head.h>
22 #include <linux/kmemleak.h>
23 #include <linux/kfence.h>
24 #include <linux/page_ext.h>
25 #include <linux/pti.h>
26 #include <linux/pgtable.h>
27 #include <linux/swap.h>
28 #include <linux/cma.h>
29 #include <linux/crash_dump.h>
30 #include "internal.h"
31 #include "slab.h"
32 #include "shuffle.h"
33 
34 #include <asm/setup.h>
35 
36 #ifdef CONFIG_DEBUG_MEMORY_INIT
37 int __meminitdata mminit_loglevel;
38 
39 /* The zonelists are simply reported, validation is manual. */
40 void __init mminit_verify_zonelist(void)
41 {
42 	int nid;
43 
44 	if (mminit_loglevel < MMINIT_VERIFY)
45 		return;
46 
47 	for_each_online_node(nid) {
48 		pg_data_t *pgdat = NODE_DATA(nid);
49 		struct zone *zone;
50 		struct zoneref *z;
51 		struct zonelist *zonelist;
52 		int i, listid, zoneid;
53 
54 		BUILD_BUG_ON(MAX_ZONELISTS > 2);
55 		for (i = 0; i < MAX_ZONELISTS * MAX_NR_ZONES; i++) {
56 
57 			/* Identify the zone and nodelist */
58 			zoneid = i % MAX_NR_ZONES;
59 			listid = i / MAX_NR_ZONES;
60 			zonelist = &pgdat->node_zonelists[listid];
61 			zone = &pgdat->node_zones[zoneid];
62 			if (!populated_zone(zone))
63 				continue;
64 
65 			/* Print information about the zonelist */
66 			printk(KERN_DEBUG "mminit::zonelist %s %d:%s = ",
67 				listid > 0 ? "thisnode" : "general", nid,
68 				zone->name);
69 
70 			/* Iterate the zonelist */
71 			for_each_zone_zonelist(zone, z, zonelist, zoneid)
72 				pr_cont("%d:%s ", zone_to_nid(zone), zone->name);
73 			pr_cont("\n");
74 		}
75 	}
76 }
77 
78 void __init mminit_verify_pageflags_layout(void)
79 {
80 	int shift, width;
81 	unsigned long or_mask, add_mask;
82 
83 	shift = BITS_PER_LONG;
84 	width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH
85 		- LAST_CPUPID_SHIFT - KASAN_TAG_WIDTH - LRU_GEN_WIDTH - LRU_REFS_WIDTH;
86 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths",
87 		"Section %d Node %d Zone %d Lastcpupid %d Kasantag %d Gen %d Tier %d Flags %d\n",
88 		SECTIONS_WIDTH,
89 		NODES_WIDTH,
90 		ZONES_WIDTH,
91 		LAST_CPUPID_WIDTH,
92 		KASAN_TAG_WIDTH,
93 		LRU_GEN_WIDTH,
94 		LRU_REFS_WIDTH,
95 		NR_PAGEFLAGS);
96 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_shifts",
97 		"Section %d Node %d Zone %d Lastcpupid %d Kasantag %d\n",
98 		SECTIONS_SHIFT,
99 		NODES_SHIFT,
100 		ZONES_SHIFT,
101 		LAST_CPUPID_SHIFT,
102 		KASAN_TAG_WIDTH);
103 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_pgshifts",
104 		"Section %lu Node %lu Zone %lu Lastcpupid %lu Kasantag %lu\n",
105 		(unsigned long)SECTIONS_PGSHIFT,
106 		(unsigned long)NODES_PGSHIFT,
107 		(unsigned long)ZONES_PGSHIFT,
108 		(unsigned long)LAST_CPUPID_PGSHIFT,
109 		(unsigned long)KASAN_TAG_PGSHIFT);
110 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodezoneid",
111 		"Node/Zone ID: %lu -> %lu\n",
112 		(unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT),
113 		(unsigned long)ZONEID_PGOFF);
114 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_usage",
115 		"location: %d -> %d layout %d -> %d unused %d -> %d page-flags\n",
116 		shift, width, width, NR_PAGEFLAGS, NR_PAGEFLAGS, 0);
117 #ifdef NODE_NOT_IN_PAGE_FLAGS
118 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
119 		"Node not in page flags");
120 #endif
121 #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
122 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
123 		"Last cpupid not in page flags");
124 #endif
125 
126 	if (SECTIONS_WIDTH) {
127 		shift -= SECTIONS_WIDTH;
128 		BUG_ON(shift != SECTIONS_PGSHIFT);
129 	}
130 	if (NODES_WIDTH) {
131 		shift -= NODES_WIDTH;
132 		BUG_ON(shift != NODES_PGSHIFT);
133 	}
134 	if (ZONES_WIDTH) {
135 		shift -= ZONES_WIDTH;
136 		BUG_ON(shift != ZONES_PGSHIFT);
137 	}
138 
139 	/* Check for bitmask overlaps */
140 	or_mask = (ZONES_MASK << ZONES_PGSHIFT) |
141 			(NODES_MASK << NODES_PGSHIFT) |
142 			(SECTIONS_MASK << SECTIONS_PGSHIFT);
143 	add_mask = (ZONES_MASK << ZONES_PGSHIFT) +
144 			(NODES_MASK << NODES_PGSHIFT) +
145 			(SECTIONS_MASK << SECTIONS_PGSHIFT);
146 	BUG_ON(or_mask != add_mask);
147 }
148 
149 static __init int set_mminit_loglevel(char *str)
150 {
151 	get_option(&str, &mminit_loglevel);
152 	return 0;
153 }
154 early_param("mminit_loglevel", set_mminit_loglevel);
155 #endif /* CONFIG_DEBUG_MEMORY_INIT */
156 
157 struct kobject *mm_kobj;
158 
159 #ifdef CONFIG_SMP
160 s32 vm_committed_as_batch = 32;
161 
162 void mm_compute_batch(int overcommit_policy)
163 {
164 	u64 memsized_batch;
165 	s32 nr = num_present_cpus();
166 	s32 batch = max_t(s32, nr*2, 32);
167 	unsigned long ram_pages = totalram_pages();
168 
169 	/*
170 	 * For policy OVERCOMMIT_NEVER, set batch size to 0.4% of
171 	 * (total memory/#cpus), and lift it to 25% for other policies
172 	 * to easy the possible lock contention for percpu_counter
173 	 * vm_committed_as, while the max limit is INT_MAX
174 	 */
175 	if (overcommit_policy == OVERCOMMIT_NEVER)
176 		memsized_batch = min_t(u64, ram_pages/nr/256, INT_MAX);
177 	else
178 		memsized_batch = min_t(u64, ram_pages/nr/4, INT_MAX);
179 
180 	vm_committed_as_batch = max_t(s32, memsized_batch, batch);
181 }
182 
183 static int __meminit mm_compute_batch_notifier(struct notifier_block *self,
184 					unsigned long action, void *arg)
185 {
186 	switch (action) {
187 	case MEM_ONLINE:
188 	case MEM_OFFLINE:
189 		mm_compute_batch(sysctl_overcommit_memory);
190 		break;
191 	default:
192 		break;
193 	}
194 	return NOTIFY_OK;
195 }
196 
197 static int __init mm_compute_batch_init(void)
198 {
199 	mm_compute_batch(sysctl_overcommit_memory);
200 	hotplug_memory_notifier(mm_compute_batch_notifier, MM_COMPUTE_BATCH_PRI);
201 	return 0;
202 }
203 
204 __initcall(mm_compute_batch_init);
205 
206 #endif
207 
208 static int __init mm_sysfs_init(void)
209 {
210 	mm_kobj = kobject_create_and_add("mm", kernel_kobj);
211 	if (!mm_kobj)
212 		return -ENOMEM;
213 
214 	return 0;
215 }
216 postcore_initcall(mm_sysfs_init);
217 
218 static unsigned long arch_zone_lowest_possible_pfn[MAX_NR_ZONES] __initdata;
219 static unsigned long arch_zone_highest_possible_pfn[MAX_NR_ZONES] __initdata;
220 static unsigned long zone_movable_pfn[MAX_NUMNODES] __initdata;
221 
222 static unsigned long required_kernelcore __initdata;
223 static unsigned long required_kernelcore_percent __initdata;
224 static unsigned long required_movablecore __initdata;
225 static unsigned long required_movablecore_percent __initdata;
226 
227 static unsigned long nr_kernel_pages __initdata;
228 static unsigned long nr_all_pages __initdata;
229 static unsigned long dma_reserve __initdata;
230 
231 static bool deferred_struct_pages __meminitdata;
232 
233 static DEFINE_PER_CPU(struct per_cpu_nodestat, boot_nodestats);
234 
235 static int __init cmdline_parse_core(char *p, unsigned long *core,
236 				     unsigned long *percent)
237 {
238 	unsigned long long coremem;
239 	char *endptr;
240 
241 	if (!p)
242 		return -EINVAL;
243 
244 	/* Value may be a percentage of total memory, otherwise bytes */
245 	coremem = simple_strtoull(p, &endptr, 0);
246 	if (*endptr == '%') {
247 		/* Paranoid check for percent values greater than 100 */
248 		WARN_ON(coremem > 100);
249 
250 		*percent = coremem;
251 	} else {
252 		coremem = memparse(p, &p);
253 		/* Paranoid check that UL is enough for the coremem value */
254 		WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX);
255 
256 		*core = coremem >> PAGE_SHIFT;
257 		*percent = 0UL;
258 	}
259 	return 0;
260 }
261 
262 bool mirrored_kernelcore __initdata_memblock;
263 
264 /*
265  * kernelcore=size sets the amount of memory for use for allocations that
266  * cannot be reclaimed or migrated.
267  */
268 static int __init cmdline_parse_kernelcore(char *p)
269 {
270 	/* parse kernelcore=mirror */
271 	if (parse_option_str(p, "mirror")) {
272 		mirrored_kernelcore = true;
273 		return 0;
274 	}
275 
276 	return cmdline_parse_core(p, &required_kernelcore,
277 				  &required_kernelcore_percent);
278 }
279 early_param("kernelcore", cmdline_parse_kernelcore);
280 
281 /*
282  * movablecore=size sets the amount of memory for use for allocations that
283  * can be reclaimed or migrated.
284  */
285 static int __init cmdline_parse_movablecore(char *p)
286 {
287 	return cmdline_parse_core(p, &required_movablecore,
288 				  &required_movablecore_percent);
289 }
290 early_param("movablecore", cmdline_parse_movablecore);
291 
292 /*
293  * early_calculate_totalpages()
294  * Sum pages in active regions for movable zone.
295  * Populate N_MEMORY for calculating usable_nodes.
296  */
297 static unsigned long __init early_calculate_totalpages(void)
298 {
299 	unsigned long totalpages = 0;
300 	unsigned long start_pfn, end_pfn;
301 	int i, nid;
302 
303 	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) {
304 		unsigned long pages = end_pfn - start_pfn;
305 
306 		totalpages += pages;
307 		if (pages)
308 			node_set_state(nid, N_MEMORY);
309 	}
310 	return totalpages;
311 }
312 
313 /*
314  * This finds a zone that can be used for ZONE_MOVABLE pages. The
315  * assumption is made that zones within a node are ordered in monotonic
316  * increasing memory addresses so that the "highest" populated zone is used
317  */
318 static void __init find_usable_zone_for_movable(void)
319 {
320 	int zone_index;
321 	for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) {
322 		if (zone_index == ZONE_MOVABLE)
323 			continue;
324 
325 		if (arch_zone_highest_possible_pfn[zone_index] >
326 				arch_zone_lowest_possible_pfn[zone_index])
327 			break;
328 	}
329 
330 	VM_BUG_ON(zone_index == -1);
331 	movable_zone = zone_index;
332 }
333 
334 /*
335  * Find the PFN the Movable zone begins in each node. Kernel memory
336  * is spread evenly between nodes as long as the nodes have enough
337  * memory. When they don't, some nodes will have more kernelcore than
338  * others
339  */
340 static void __init find_zone_movable_pfns_for_nodes(void)
341 {
342 	int i, nid;
343 	unsigned long usable_startpfn;
344 	unsigned long kernelcore_node, kernelcore_remaining;
345 	/* save the state before borrow the nodemask */
346 	nodemask_t saved_node_state = node_states[N_MEMORY];
347 	unsigned long totalpages = early_calculate_totalpages();
348 	int usable_nodes = nodes_weight(node_states[N_MEMORY]);
349 	struct memblock_region *r;
350 
351 	/* Need to find movable_zone earlier when movable_node is specified. */
352 	find_usable_zone_for_movable();
353 
354 	/*
355 	 * If movable_node is specified, ignore kernelcore and movablecore
356 	 * options.
357 	 */
358 	if (movable_node_is_enabled()) {
359 		for_each_mem_region(r) {
360 			if (!memblock_is_hotpluggable(r))
361 				continue;
362 
363 			nid = memblock_get_region_node(r);
364 
365 			usable_startpfn = PFN_DOWN(r->base);
366 			zone_movable_pfn[nid] = zone_movable_pfn[nid] ?
367 				min(usable_startpfn, zone_movable_pfn[nid]) :
368 				usable_startpfn;
369 		}
370 
371 		goto out2;
372 	}
373 
374 	/*
375 	 * If kernelcore=mirror is specified, ignore movablecore option
376 	 */
377 	if (mirrored_kernelcore) {
378 		bool mem_below_4gb_not_mirrored = false;
379 
380 		if (!memblock_has_mirror()) {
381 			pr_warn("The system has no mirror memory, ignore kernelcore=mirror.\n");
382 			goto out;
383 		}
384 
385 		if (is_kdump_kernel()) {
386 			pr_warn("The system is under kdump, ignore kernelcore=mirror.\n");
387 			goto out;
388 		}
389 
390 		for_each_mem_region(r) {
391 			if (memblock_is_mirror(r))
392 				continue;
393 
394 			nid = memblock_get_region_node(r);
395 
396 			usable_startpfn = memblock_region_memory_base_pfn(r);
397 
398 			if (usable_startpfn < PHYS_PFN(SZ_4G)) {
399 				mem_below_4gb_not_mirrored = true;
400 				continue;
401 			}
402 
403 			zone_movable_pfn[nid] = zone_movable_pfn[nid] ?
404 				min(usable_startpfn, zone_movable_pfn[nid]) :
405 				usable_startpfn;
406 		}
407 
408 		if (mem_below_4gb_not_mirrored)
409 			pr_warn("This configuration results in unmirrored kernel memory.\n");
410 
411 		goto out2;
412 	}
413 
414 	/*
415 	 * If kernelcore=nn% or movablecore=nn% was specified, calculate the
416 	 * amount of necessary memory.
417 	 */
418 	if (required_kernelcore_percent)
419 		required_kernelcore = (totalpages * 100 * required_kernelcore_percent) /
420 				       10000UL;
421 	if (required_movablecore_percent)
422 		required_movablecore = (totalpages * 100 * required_movablecore_percent) /
423 					10000UL;
424 
425 	/*
426 	 * If movablecore= was specified, calculate what size of
427 	 * kernelcore that corresponds so that memory usable for
428 	 * any allocation type is evenly spread. If both kernelcore
429 	 * and movablecore are specified, then the value of kernelcore
430 	 * will be used for required_kernelcore if it's greater than
431 	 * what movablecore would have allowed.
432 	 */
433 	if (required_movablecore) {
434 		unsigned long corepages;
435 
436 		/*
437 		 * Round-up so that ZONE_MOVABLE is at least as large as what
438 		 * was requested by the user
439 		 */
440 		required_movablecore =
441 			roundup(required_movablecore, MAX_ORDER_NR_PAGES);
442 		required_movablecore = min(totalpages, required_movablecore);
443 		corepages = totalpages - required_movablecore;
444 
445 		required_kernelcore = max(required_kernelcore, corepages);
446 	}
447 
448 	/*
449 	 * If kernelcore was not specified or kernelcore size is larger
450 	 * than totalpages, there is no ZONE_MOVABLE.
451 	 */
452 	if (!required_kernelcore || required_kernelcore >= totalpages)
453 		goto out;
454 
455 	/* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
456 	usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone];
457 
458 restart:
459 	/* Spread kernelcore memory as evenly as possible throughout nodes */
460 	kernelcore_node = required_kernelcore / usable_nodes;
461 	for_each_node_state(nid, N_MEMORY) {
462 		unsigned long start_pfn, end_pfn;
463 
464 		/*
465 		 * Recalculate kernelcore_node if the division per node
466 		 * now exceeds what is necessary to satisfy the requested
467 		 * amount of memory for the kernel
468 		 */
469 		if (required_kernelcore < kernelcore_node)
470 			kernelcore_node = required_kernelcore / usable_nodes;
471 
472 		/*
473 		 * As the map is walked, we track how much memory is usable
474 		 * by the kernel using kernelcore_remaining. When it is
475 		 * 0, the rest of the node is usable by ZONE_MOVABLE
476 		 */
477 		kernelcore_remaining = kernelcore_node;
478 
479 		/* Go through each range of PFNs within this node */
480 		for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
481 			unsigned long size_pages;
482 
483 			start_pfn = max(start_pfn, zone_movable_pfn[nid]);
484 			if (start_pfn >= end_pfn)
485 				continue;
486 
487 			/* Account for what is only usable for kernelcore */
488 			if (start_pfn < usable_startpfn) {
489 				unsigned long kernel_pages;
490 				kernel_pages = min(end_pfn, usable_startpfn)
491 								- start_pfn;
492 
493 				kernelcore_remaining -= min(kernel_pages,
494 							kernelcore_remaining);
495 				required_kernelcore -= min(kernel_pages,
496 							required_kernelcore);
497 
498 				/* Continue if range is now fully accounted */
499 				if (end_pfn <= usable_startpfn) {
500 
501 					/*
502 					 * Push zone_movable_pfn to the end so
503 					 * that if we have to rebalance
504 					 * kernelcore across nodes, we will
505 					 * not double account here
506 					 */
507 					zone_movable_pfn[nid] = end_pfn;
508 					continue;
509 				}
510 				start_pfn = usable_startpfn;
511 			}
512 
513 			/*
514 			 * The usable PFN range for ZONE_MOVABLE is from
515 			 * start_pfn->end_pfn. Calculate size_pages as the
516 			 * number of pages used as kernelcore
517 			 */
518 			size_pages = end_pfn - start_pfn;
519 			if (size_pages > kernelcore_remaining)
520 				size_pages = kernelcore_remaining;
521 			zone_movable_pfn[nid] = start_pfn + size_pages;
522 
523 			/*
524 			 * Some kernelcore has been met, update counts and
525 			 * break if the kernelcore for this node has been
526 			 * satisfied
527 			 */
528 			required_kernelcore -= min(required_kernelcore,
529 								size_pages);
530 			kernelcore_remaining -= size_pages;
531 			if (!kernelcore_remaining)
532 				break;
533 		}
534 	}
535 
536 	/*
537 	 * If there is still required_kernelcore, we do another pass with one
538 	 * less node in the count. This will push zone_movable_pfn[nid] further
539 	 * along on the nodes that still have memory until kernelcore is
540 	 * satisfied
541 	 */
542 	usable_nodes--;
543 	if (usable_nodes && required_kernelcore > usable_nodes)
544 		goto restart;
545 
546 out2:
547 	/* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
548 	for (nid = 0; nid < MAX_NUMNODES; nid++) {
549 		unsigned long start_pfn, end_pfn;
550 
551 		zone_movable_pfn[nid] =
552 			roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES);
553 
554 		get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
555 		if (zone_movable_pfn[nid] >= end_pfn)
556 			zone_movable_pfn[nid] = 0;
557 	}
558 
559 out:
560 	/* restore the node_state */
561 	node_states[N_MEMORY] = saved_node_state;
562 }
563 
564 void __meminit __init_single_page(struct page *page, unsigned long pfn,
565 				unsigned long zone, int nid)
566 {
567 	mm_zero_struct_page(page);
568 	set_page_links(page, zone, nid, pfn);
569 	init_page_count(page);
570 	page_mapcount_reset(page);
571 	page_cpupid_reset_last(page);
572 	page_kasan_tag_reset(page);
573 
574 	INIT_LIST_HEAD(&page->lru);
575 #ifdef WANT_PAGE_VIRTUAL
576 	/* The shift won't overflow because ZONE_NORMAL is below 4G. */
577 	if (!is_highmem_idx(zone))
578 		set_page_address(page, __va(pfn << PAGE_SHIFT));
579 #endif
580 }
581 
582 #ifdef CONFIG_NUMA
583 /*
584  * During memory init memblocks map pfns to nids. The search is expensive and
585  * this caches recent lookups. The implementation of __early_pfn_to_nid
586  * treats start/end as pfns.
587  */
588 struct mminit_pfnnid_cache {
589 	unsigned long last_start;
590 	unsigned long last_end;
591 	int last_nid;
592 };
593 
594 static struct mminit_pfnnid_cache early_pfnnid_cache __meminitdata;
595 
596 /*
597  * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
598  */
599 static int __meminit __early_pfn_to_nid(unsigned long pfn,
600 					struct mminit_pfnnid_cache *state)
601 {
602 	unsigned long start_pfn, end_pfn;
603 	int nid;
604 
605 	if (state->last_start <= pfn && pfn < state->last_end)
606 		return state->last_nid;
607 
608 	nid = memblock_search_pfn_nid(pfn, &start_pfn, &end_pfn);
609 	if (nid != NUMA_NO_NODE) {
610 		state->last_start = start_pfn;
611 		state->last_end = end_pfn;
612 		state->last_nid = nid;
613 	}
614 
615 	return nid;
616 }
617 
618 int __meminit early_pfn_to_nid(unsigned long pfn)
619 {
620 	static DEFINE_SPINLOCK(early_pfn_lock);
621 	int nid;
622 
623 	spin_lock(&early_pfn_lock);
624 	nid = __early_pfn_to_nid(pfn, &early_pfnnid_cache);
625 	if (nid < 0)
626 		nid = first_online_node;
627 	spin_unlock(&early_pfn_lock);
628 
629 	return nid;
630 }
631 
632 int hashdist = HASHDIST_DEFAULT;
633 
634 static int __init set_hashdist(char *str)
635 {
636 	if (!str)
637 		return 0;
638 	hashdist = simple_strtoul(str, &str, 0);
639 	return 1;
640 }
641 __setup("hashdist=", set_hashdist);
642 
643 static inline void fixup_hashdist(void)
644 {
645 	if (num_node_state(N_MEMORY) == 1)
646 		hashdist = 0;
647 }
648 #else
649 static inline void fixup_hashdist(void) {}
650 #endif /* CONFIG_NUMA */
651 
652 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
653 static inline void pgdat_set_deferred_range(pg_data_t *pgdat)
654 {
655 	pgdat->first_deferred_pfn = ULONG_MAX;
656 }
657 
658 /* Returns true if the struct page for the pfn is initialised */
659 static inline bool __meminit early_page_initialised(unsigned long pfn, int nid)
660 {
661 	if (node_online(nid) && pfn >= NODE_DATA(nid)->first_deferred_pfn)
662 		return false;
663 
664 	return true;
665 }
666 
667 /*
668  * Returns true when the remaining initialisation should be deferred until
669  * later in the boot cycle when it can be parallelised.
670  */
671 static bool __meminit
672 defer_init(int nid, unsigned long pfn, unsigned long end_pfn)
673 {
674 	static unsigned long prev_end_pfn, nr_initialised;
675 
676 	if (early_page_ext_enabled())
677 		return false;
678 	/*
679 	 * prev_end_pfn static that contains the end of previous zone
680 	 * No need to protect because called very early in boot before smp_init.
681 	 */
682 	if (prev_end_pfn != end_pfn) {
683 		prev_end_pfn = end_pfn;
684 		nr_initialised = 0;
685 	}
686 
687 	/* Always populate low zones for address-constrained allocations */
688 	if (end_pfn < pgdat_end_pfn(NODE_DATA(nid)))
689 		return false;
690 
691 	if (NODE_DATA(nid)->first_deferred_pfn != ULONG_MAX)
692 		return true;
693 	/*
694 	 * We start only with one section of pages, more pages are added as
695 	 * needed until the rest of deferred pages are initialized.
696 	 */
697 	nr_initialised++;
698 	if ((nr_initialised > PAGES_PER_SECTION) &&
699 	    (pfn & (PAGES_PER_SECTION - 1)) == 0) {
700 		NODE_DATA(nid)->first_deferred_pfn = pfn;
701 		return true;
702 	}
703 	return false;
704 }
705 
706 static void __meminit init_reserved_page(unsigned long pfn, int nid)
707 {
708 	pg_data_t *pgdat;
709 	int zid;
710 
711 	if (early_page_initialised(pfn, nid))
712 		return;
713 
714 	pgdat = NODE_DATA(nid);
715 
716 	for (zid = 0; zid < MAX_NR_ZONES; zid++) {
717 		struct zone *zone = &pgdat->node_zones[zid];
718 
719 		if (zone_spans_pfn(zone, pfn))
720 			break;
721 	}
722 	__init_single_page(pfn_to_page(pfn), pfn, zid, nid);
723 }
724 #else
725 static inline void pgdat_set_deferred_range(pg_data_t *pgdat) {}
726 
727 static inline bool early_page_initialised(unsigned long pfn, int nid)
728 {
729 	return true;
730 }
731 
732 static inline bool defer_init(int nid, unsigned long pfn, unsigned long end_pfn)
733 {
734 	return false;
735 }
736 
737 static inline void init_reserved_page(unsigned long pfn, int nid)
738 {
739 }
740 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
741 
742 /*
743  * Initialised pages do not have PageReserved set. This function is
744  * called for each range allocated by the bootmem allocator and
745  * marks the pages PageReserved. The remaining valid pages are later
746  * sent to the buddy page allocator.
747  */
748 void __meminit reserve_bootmem_region(phys_addr_t start,
749 				      phys_addr_t end, int nid)
750 {
751 	unsigned long start_pfn = PFN_DOWN(start);
752 	unsigned long end_pfn = PFN_UP(end);
753 
754 	for (; start_pfn < end_pfn; start_pfn++) {
755 		if (pfn_valid(start_pfn)) {
756 			struct page *page = pfn_to_page(start_pfn);
757 
758 			init_reserved_page(start_pfn, nid);
759 
760 			/* Avoid false-positive PageTail() */
761 			INIT_LIST_HEAD(&page->lru);
762 
763 			/*
764 			 * no need for atomic set_bit because the struct
765 			 * page is not visible yet so nobody should
766 			 * access it yet.
767 			 */
768 			__SetPageReserved(page);
769 		}
770 	}
771 }
772 
773 /* If zone is ZONE_MOVABLE but memory is mirrored, it is an overlapped init */
774 static bool __meminit
775 overlap_memmap_init(unsigned long zone, unsigned long *pfn)
776 {
777 	static struct memblock_region *r;
778 
779 	if (mirrored_kernelcore && zone == ZONE_MOVABLE) {
780 		if (!r || *pfn >= memblock_region_memory_end_pfn(r)) {
781 			for_each_mem_region(r) {
782 				if (*pfn < memblock_region_memory_end_pfn(r))
783 					break;
784 			}
785 		}
786 		if (*pfn >= memblock_region_memory_base_pfn(r) &&
787 		    memblock_is_mirror(r)) {
788 			*pfn = memblock_region_memory_end_pfn(r);
789 			return true;
790 		}
791 	}
792 	return false;
793 }
794 
795 /*
796  * Only struct pages that correspond to ranges defined by memblock.memory
797  * are zeroed and initialized by going through __init_single_page() during
798  * memmap_init_zone_range().
799  *
800  * But, there could be struct pages that correspond to holes in
801  * memblock.memory. This can happen because of the following reasons:
802  * - physical memory bank size is not necessarily the exact multiple of the
803  *   arbitrary section size
804  * - early reserved memory may not be listed in memblock.memory
805  * - non-memory regions covered by the contigious flatmem mapping
806  * - memory layouts defined with memmap= kernel parameter may not align
807  *   nicely with memmap sections
808  *
809  * Explicitly initialize those struct pages so that:
810  * - PG_Reserved is set
811  * - zone and node links point to zone and node that span the page if the
812  *   hole is in the middle of a zone
813  * - zone and node links point to adjacent zone/node if the hole falls on
814  *   the zone boundary; the pages in such holes will be prepended to the
815  *   zone/node above the hole except for the trailing pages in the last
816  *   section that will be appended to the zone/node below.
817  */
818 static void __init init_unavailable_range(unsigned long spfn,
819 					  unsigned long epfn,
820 					  int zone, int node)
821 {
822 	unsigned long pfn;
823 	u64 pgcnt = 0;
824 
825 	for (pfn = spfn; pfn < epfn; pfn++) {
826 		if (!pfn_valid(pageblock_start_pfn(pfn))) {
827 			pfn = pageblock_end_pfn(pfn) - 1;
828 			continue;
829 		}
830 		__init_single_page(pfn_to_page(pfn), pfn, zone, node);
831 		__SetPageReserved(pfn_to_page(pfn));
832 		pgcnt++;
833 	}
834 
835 	if (pgcnt)
836 		pr_info("On node %d, zone %s: %lld pages in unavailable ranges\n",
837 			node, zone_names[zone], pgcnt);
838 }
839 
840 /*
841  * Initially all pages are reserved - free ones are freed
842  * up by memblock_free_all() once the early boot process is
843  * done. Non-atomic initialization, single-pass.
844  *
845  * All aligned pageblocks are initialized to the specified migratetype
846  * (usually MIGRATE_MOVABLE). Besides setting the migratetype, no related
847  * zone stats (e.g., nr_isolate_pageblock) are touched.
848  */
849 void __meminit memmap_init_range(unsigned long size, int nid, unsigned long zone,
850 		unsigned long start_pfn, unsigned long zone_end_pfn,
851 		enum meminit_context context,
852 		struct vmem_altmap *altmap, int migratetype)
853 {
854 	unsigned long pfn, end_pfn = start_pfn + size;
855 	struct page *page;
856 
857 	if (highest_memmap_pfn < end_pfn - 1)
858 		highest_memmap_pfn = end_pfn - 1;
859 
860 #ifdef CONFIG_ZONE_DEVICE
861 	/*
862 	 * Honor reservation requested by the driver for this ZONE_DEVICE
863 	 * memory. We limit the total number of pages to initialize to just
864 	 * those that might contain the memory mapping. We will defer the
865 	 * ZONE_DEVICE page initialization until after we have released
866 	 * the hotplug lock.
867 	 */
868 	if (zone == ZONE_DEVICE) {
869 		if (!altmap)
870 			return;
871 
872 		if (start_pfn == altmap->base_pfn)
873 			start_pfn += altmap->reserve;
874 		end_pfn = altmap->base_pfn + vmem_altmap_offset(altmap);
875 	}
876 #endif
877 
878 	for (pfn = start_pfn; pfn < end_pfn; ) {
879 		/*
880 		 * There can be holes in boot-time mem_map[]s handed to this
881 		 * function.  They do not exist on hotplugged memory.
882 		 */
883 		if (context == MEMINIT_EARLY) {
884 			if (overlap_memmap_init(zone, &pfn))
885 				continue;
886 			if (defer_init(nid, pfn, zone_end_pfn)) {
887 				deferred_struct_pages = true;
888 				break;
889 			}
890 		}
891 
892 		page = pfn_to_page(pfn);
893 		__init_single_page(page, pfn, zone, nid);
894 		if (context == MEMINIT_HOTPLUG)
895 			__SetPageReserved(page);
896 
897 		/*
898 		 * Usually, we want to mark the pageblock MIGRATE_MOVABLE,
899 		 * such that unmovable allocations won't be scattered all
900 		 * over the place during system boot.
901 		 */
902 		if (pageblock_aligned(pfn)) {
903 			set_pageblock_migratetype(page, migratetype);
904 			cond_resched();
905 		}
906 		pfn++;
907 	}
908 }
909 
910 static void __init memmap_init_zone_range(struct zone *zone,
911 					  unsigned long start_pfn,
912 					  unsigned long end_pfn,
913 					  unsigned long *hole_pfn)
914 {
915 	unsigned long zone_start_pfn = zone->zone_start_pfn;
916 	unsigned long zone_end_pfn = zone_start_pfn + zone->spanned_pages;
917 	int nid = zone_to_nid(zone), zone_id = zone_idx(zone);
918 
919 	start_pfn = clamp(start_pfn, zone_start_pfn, zone_end_pfn);
920 	end_pfn = clamp(end_pfn, zone_start_pfn, zone_end_pfn);
921 
922 	if (start_pfn >= end_pfn)
923 		return;
924 
925 	memmap_init_range(end_pfn - start_pfn, nid, zone_id, start_pfn,
926 			  zone_end_pfn, MEMINIT_EARLY, NULL, MIGRATE_MOVABLE);
927 
928 	if (*hole_pfn < start_pfn)
929 		init_unavailable_range(*hole_pfn, start_pfn, zone_id, nid);
930 
931 	*hole_pfn = end_pfn;
932 }
933 
934 static void __init memmap_init(void)
935 {
936 	unsigned long start_pfn, end_pfn;
937 	unsigned long hole_pfn = 0;
938 	int i, j, zone_id = 0, nid;
939 
940 	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) {
941 		struct pglist_data *node = NODE_DATA(nid);
942 
943 		for (j = 0; j < MAX_NR_ZONES; j++) {
944 			struct zone *zone = node->node_zones + j;
945 
946 			if (!populated_zone(zone))
947 				continue;
948 
949 			memmap_init_zone_range(zone, start_pfn, end_pfn,
950 					       &hole_pfn);
951 			zone_id = j;
952 		}
953 	}
954 
955 #ifdef CONFIG_SPARSEMEM
956 	/*
957 	 * Initialize the memory map for hole in the range [memory_end,
958 	 * section_end].
959 	 * Append the pages in this hole to the highest zone in the last
960 	 * node.
961 	 * The call to init_unavailable_range() is outside the ifdef to
962 	 * silence the compiler warining about zone_id set but not used;
963 	 * for FLATMEM it is a nop anyway
964 	 */
965 	end_pfn = round_up(end_pfn, PAGES_PER_SECTION);
966 	if (hole_pfn < end_pfn)
967 #endif
968 		init_unavailable_range(hole_pfn, end_pfn, zone_id, nid);
969 }
970 
971 #ifdef CONFIG_ZONE_DEVICE
972 static void __ref __init_zone_device_page(struct page *page, unsigned long pfn,
973 					  unsigned long zone_idx, int nid,
974 					  struct dev_pagemap *pgmap)
975 {
976 
977 	__init_single_page(page, pfn, zone_idx, nid);
978 
979 	/*
980 	 * Mark page reserved as it will need to wait for onlining
981 	 * phase for it to be fully associated with a zone.
982 	 *
983 	 * We can use the non-atomic __set_bit operation for setting
984 	 * the flag as we are still initializing the pages.
985 	 */
986 	__SetPageReserved(page);
987 
988 	/*
989 	 * ZONE_DEVICE pages union ->lru with a ->pgmap back pointer
990 	 * and zone_device_data.  It is a bug if a ZONE_DEVICE page is
991 	 * ever freed or placed on a driver-private list.
992 	 */
993 	page->pgmap = pgmap;
994 	page->zone_device_data = NULL;
995 
996 	/*
997 	 * Mark the block movable so that blocks are reserved for
998 	 * movable at startup. This will force kernel allocations
999 	 * to reserve their blocks rather than leaking throughout
1000 	 * the address space during boot when many long-lived
1001 	 * kernel allocations are made.
1002 	 *
1003 	 * Please note that MEMINIT_HOTPLUG path doesn't clear memmap
1004 	 * because this is done early in section_activate()
1005 	 */
1006 	if (pageblock_aligned(pfn)) {
1007 		set_pageblock_migratetype(page, MIGRATE_MOVABLE);
1008 		cond_resched();
1009 	}
1010 
1011 	/*
1012 	 * ZONE_DEVICE pages are released directly to the driver page allocator
1013 	 * which will set the page count to 1 when allocating the page.
1014 	 */
1015 	if (pgmap->type == MEMORY_DEVICE_PRIVATE ||
1016 	    pgmap->type == MEMORY_DEVICE_COHERENT)
1017 		set_page_count(page, 0);
1018 }
1019 
1020 /*
1021  * With compound page geometry and when struct pages are stored in ram most
1022  * tail pages are reused. Consequently, the amount of unique struct pages to
1023  * initialize is a lot smaller that the total amount of struct pages being
1024  * mapped. This is a paired / mild layering violation with explicit knowledge
1025  * of how the sparse_vmemmap internals handle compound pages in the lack
1026  * of an altmap. See vmemmap_populate_compound_pages().
1027  */
1028 static inline unsigned long compound_nr_pages(struct vmem_altmap *altmap,
1029 					      struct dev_pagemap *pgmap)
1030 {
1031 	if (!vmemmap_can_optimize(altmap, pgmap))
1032 		return pgmap_vmemmap_nr(pgmap);
1033 
1034 	return VMEMMAP_RESERVE_NR * (PAGE_SIZE / sizeof(struct page));
1035 }
1036 
1037 static void __ref memmap_init_compound(struct page *head,
1038 				       unsigned long head_pfn,
1039 				       unsigned long zone_idx, int nid,
1040 				       struct dev_pagemap *pgmap,
1041 				       unsigned long nr_pages)
1042 {
1043 	unsigned long pfn, end_pfn = head_pfn + nr_pages;
1044 	unsigned int order = pgmap->vmemmap_shift;
1045 
1046 	__SetPageHead(head);
1047 	for (pfn = head_pfn + 1; pfn < end_pfn; pfn++) {
1048 		struct page *page = pfn_to_page(pfn);
1049 
1050 		__init_zone_device_page(page, pfn, zone_idx, nid, pgmap);
1051 		prep_compound_tail(head, pfn - head_pfn);
1052 		set_page_count(page, 0);
1053 
1054 		/*
1055 		 * The first tail page stores important compound page info.
1056 		 * Call prep_compound_head() after the first tail page has
1057 		 * been initialized, to not have the data overwritten.
1058 		 */
1059 		if (pfn == head_pfn + 1)
1060 			prep_compound_head(head, order);
1061 	}
1062 }
1063 
1064 void __ref memmap_init_zone_device(struct zone *zone,
1065 				   unsigned long start_pfn,
1066 				   unsigned long nr_pages,
1067 				   struct dev_pagemap *pgmap)
1068 {
1069 	unsigned long pfn, end_pfn = start_pfn + nr_pages;
1070 	struct pglist_data *pgdat = zone->zone_pgdat;
1071 	struct vmem_altmap *altmap = pgmap_altmap(pgmap);
1072 	unsigned int pfns_per_compound = pgmap_vmemmap_nr(pgmap);
1073 	unsigned long zone_idx = zone_idx(zone);
1074 	unsigned long start = jiffies;
1075 	int nid = pgdat->node_id;
1076 
1077 	if (WARN_ON_ONCE(!pgmap || zone_idx != ZONE_DEVICE))
1078 		return;
1079 
1080 	/*
1081 	 * The call to memmap_init should have already taken care
1082 	 * of the pages reserved for the memmap, so we can just jump to
1083 	 * the end of that region and start processing the device pages.
1084 	 */
1085 	if (altmap) {
1086 		start_pfn = altmap->base_pfn + vmem_altmap_offset(altmap);
1087 		nr_pages = end_pfn - start_pfn;
1088 	}
1089 
1090 	for (pfn = start_pfn; pfn < end_pfn; pfn += pfns_per_compound) {
1091 		struct page *page = pfn_to_page(pfn);
1092 
1093 		__init_zone_device_page(page, pfn, zone_idx, nid, pgmap);
1094 
1095 		if (pfns_per_compound == 1)
1096 			continue;
1097 
1098 		memmap_init_compound(page, pfn, zone_idx, nid, pgmap,
1099 				     compound_nr_pages(altmap, pgmap));
1100 	}
1101 
1102 	pr_debug("%s initialised %lu pages in %ums\n", __func__,
1103 		nr_pages, jiffies_to_msecs(jiffies - start));
1104 }
1105 #endif
1106 
1107 /*
1108  * The zone ranges provided by the architecture do not include ZONE_MOVABLE
1109  * because it is sized independent of architecture. Unlike the other zones,
1110  * the starting point for ZONE_MOVABLE is not fixed. It may be different
1111  * in each node depending on the size of each node and how evenly kernelcore
1112  * is distributed. This helper function adjusts the zone ranges
1113  * provided by the architecture for a given node by using the end of the
1114  * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
1115  * zones within a node are in order of monotonic increases memory addresses
1116  */
1117 static void __init adjust_zone_range_for_zone_movable(int nid,
1118 					unsigned long zone_type,
1119 					unsigned long node_end_pfn,
1120 					unsigned long *zone_start_pfn,
1121 					unsigned long *zone_end_pfn)
1122 {
1123 	/* Only adjust if ZONE_MOVABLE is on this node */
1124 	if (zone_movable_pfn[nid]) {
1125 		/* Size ZONE_MOVABLE */
1126 		if (zone_type == ZONE_MOVABLE) {
1127 			*zone_start_pfn = zone_movable_pfn[nid];
1128 			*zone_end_pfn = min(node_end_pfn,
1129 				arch_zone_highest_possible_pfn[movable_zone]);
1130 
1131 		/* Adjust for ZONE_MOVABLE starting within this range */
1132 		} else if (!mirrored_kernelcore &&
1133 			*zone_start_pfn < zone_movable_pfn[nid] &&
1134 			*zone_end_pfn > zone_movable_pfn[nid]) {
1135 			*zone_end_pfn = zone_movable_pfn[nid];
1136 
1137 		/* Check if this whole range is within ZONE_MOVABLE */
1138 		} else if (*zone_start_pfn >= zone_movable_pfn[nid])
1139 			*zone_start_pfn = *zone_end_pfn;
1140 	}
1141 }
1142 
1143 /*
1144  * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
1145  * then all holes in the requested range will be accounted for.
1146  */
1147 unsigned long __init __absent_pages_in_range(int nid,
1148 				unsigned long range_start_pfn,
1149 				unsigned long range_end_pfn)
1150 {
1151 	unsigned long nr_absent = range_end_pfn - range_start_pfn;
1152 	unsigned long start_pfn, end_pfn;
1153 	int i;
1154 
1155 	for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
1156 		start_pfn = clamp(start_pfn, range_start_pfn, range_end_pfn);
1157 		end_pfn = clamp(end_pfn, range_start_pfn, range_end_pfn);
1158 		nr_absent -= end_pfn - start_pfn;
1159 	}
1160 	return nr_absent;
1161 }
1162 
1163 /**
1164  * absent_pages_in_range - Return number of page frames in holes within a range
1165  * @start_pfn: The start PFN to start searching for holes
1166  * @end_pfn: The end PFN to stop searching for holes
1167  *
1168  * Return: the number of pages frames in memory holes within a range.
1169  */
1170 unsigned long __init absent_pages_in_range(unsigned long start_pfn,
1171 							unsigned long end_pfn)
1172 {
1173 	return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn);
1174 }
1175 
1176 /* Return the number of page frames in holes in a zone on a node */
1177 static unsigned long __init zone_absent_pages_in_node(int nid,
1178 					unsigned long zone_type,
1179 					unsigned long zone_start_pfn,
1180 					unsigned long zone_end_pfn)
1181 {
1182 	unsigned long nr_absent;
1183 
1184 	/* zone is empty, we don't have any absent pages */
1185 	if (zone_start_pfn == zone_end_pfn)
1186 		return 0;
1187 
1188 	nr_absent = __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
1189 
1190 	/*
1191 	 * ZONE_MOVABLE handling.
1192 	 * Treat pages to be ZONE_MOVABLE in ZONE_NORMAL as absent pages
1193 	 * and vice versa.
1194 	 */
1195 	if (mirrored_kernelcore && zone_movable_pfn[nid]) {
1196 		unsigned long start_pfn, end_pfn;
1197 		struct memblock_region *r;
1198 
1199 		for_each_mem_region(r) {
1200 			start_pfn = clamp(memblock_region_memory_base_pfn(r),
1201 					  zone_start_pfn, zone_end_pfn);
1202 			end_pfn = clamp(memblock_region_memory_end_pfn(r),
1203 					zone_start_pfn, zone_end_pfn);
1204 
1205 			if (zone_type == ZONE_MOVABLE &&
1206 			    memblock_is_mirror(r))
1207 				nr_absent += end_pfn - start_pfn;
1208 
1209 			if (zone_type == ZONE_NORMAL &&
1210 			    !memblock_is_mirror(r))
1211 				nr_absent += end_pfn - start_pfn;
1212 		}
1213 	}
1214 
1215 	return nr_absent;
1216 }
1217 
1218 /*
1219  * Return the number of pages a zone spans in a node, including holes
1220  * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
1221  */
1222 static unsigned long __init zone_spanned_pages_in_node(int nid,
1223 					unsigned long zone_type,
1224 					unsigned long node_start_pfn,
1225 					unsigned long node_end_pfn,
1226 					unsigned long *zone_start_pfn,
1227 					unsigned long *zone_end_pfn)
1228 {
1229 	unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type];
1230 	unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type];
1231 
1232 	/* Get the start and end of the zone */
1233 	*zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high);
1234 	*zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high);
1235 	adjust_zone_range_for_zone_movable(nid, zone_type, node_end_pfn,
1236 					   zone_start_pfn, zone_end_pfn);
1237 
1238 	/* Check that this node has pages within the zone's required range */
1239 	if (*zone_end_pfn < node_start_pfn || *zone_start_pfn > node_end_pfn)
1240 		return 0;
1241 
1242 	/* Move the zone boundaries inside the node if necessary */
1243 	*zone_end_pfn = min(*zone_end_pfn, node_end_pfn);
1244 	*zone_start_pfn = max(*zone_start_pfn, node_start_pfn);
1245 
1246 	/* Return the spanned pages */
1247 	return *zone_end_pfn - *zone_start_pfn;
1248 }
1249 
1250 static void __init reset_memoryless_node_totalpages(struct pglist_data *pgdat)
1251 {
1252 	struct zone *z;
1253 
1254 	for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++) {
1255 		z->zone_start_pfn = 0;
1256 		z->spanned_pages = 0;
1257 		z->present_pages = 0;
1258 #if defined(CONFIG_MEMORY_HOTPLUG)
1259 		z->present_early_pages = 0;
1260 #endif
1261 	}
1262 
1263 	pgdat->node_spanned_pages = 0;
1264 	pgdat->node_present_pages = 0;
1265 	pr_debug("On node %d totalpages: 0\n", pgdat->node_id);
1266 }
1267 
1268 static void __init calculate_node_totalpages(struct pglist_data *pgdat,
1269 						unsigned long node_start_pfn,
1270 						unsigned long node_end_pfn)
1271 {
1272 	unsigned long realtotalpages = 0, totalpages = 0;
1273 	enum zone_type i;
1274 
1275 	for (i = 0; i < MAX_NR_ZONES; i++) {
1276 		struct zone *zone = pgdat->node_zones + i;
1277 		unsigned long zone_start_pfn, zone_end_pfn;
1278 		unsigned long spanned, absent;
1279 		unsigned long real_size;
1280 
1281 		spanned = zone_spanned_pages_in_node(pgdat->node_id, i,
1282 						     node_start_pfn,
1283 						     node_end_pfn,
1284 						     &zone_start_pfn,
1285 						     &zone_end_pfn);
1286 		absent = zone_absent_pages_in_node(pgdat->node_id, i,
1287 						   zone_start_pfn,
1288 						   zone_end_pfn);
1289 
1290 		real_size = spanned - absent;
1291 
1292 		if (spanned)
1293 			zone->zone_start_pfn = zone_start_pfn;
1294 		else
1295 			zone->zone_start_pfn = 0;
1296 		zone->spanned_pages = spanned;
1297 		zone->present_pages = real_size;
1298 #if defined(CONFIG_MEMORY_HOTPLUG)
1299 		zone->present_early_pages = real_size;
1300 #endif
1301 
1302 		totalpages += spanned;
1303 		realtotalpages += real_size;
1304 	}
1305 
1306 	pgdat->node_spanned_pages = totalpages;
1307 	pgdat->node_present_pages = realtotalpages;
1308 	pr_debug("On node %d totalpages: %lu\n", pgdat->node_id, realtotalpages);
1309 }
1310 
1311 static unsigned long __init calc_memmap_size(unsigned long spanned_pages,
1312 						unsigned long present_pages)
1313 {
1314 	unsigned long pages = spanned_pages;
1315 
1316 	/*
1317 	 * Provide a more accurate estimation if there are holes within
1318 	 * the zone and SPARSEMEM is in use. If there are holes within the
1319 	 * zone, each populated memory region may cost us one or two extra
1320 	 * memmap pages due to alignment because memmap pages for each
1321 	 * populated regions may not be naturally aligned on page boundary.
1322 	 * So the (present_pages >> 4) heuristic is a tradeoff for that.
1323 	 */
1324 	if (spanned_pages > present_pages + (present_pages >> 4) &&
1325 	    IS_ENABLED(CONFIG_SPARSEMEM))
1326 		pages = present_pages;
1327 
1328 	return PAGE_ALIGN(pages * sizeof(struct page)) >> PAGE_SHIFT;
1329 }
1330 
1331 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1332 static void pgdat_init_split_queue(struct pglist_data *pgdat)
1333 {
1334 	struct deferred_split *ds_queue = &pgdat->deferred_split_queue;
1335 
1336 	spin_lock_init(&ds_queue->split_queue_lock);
1337 	INIT_LIST_HEAD(&ds_queue->split_queue);
1338 	ds_queue->split_queue_len = 0;
1339 }
1340 #else
1341 static void pgdat_init_split_queue(struct pglist_data *pgdat) {}
1342 #endif
1343 
1344 #ifdef CONFIG_COMPACTION
1345 static void pgdat_init_kcompactd(struct pglist_data *pgdat)
1346 {
1347 	init_waitqueue_head(&pgdat->kcompactd_wait);
1348 }
1349 #else
1350 static void pgdat_init_kcompactd(struct pglist_data *pgdat) {}
1351 #endif
1352 
1353 static void __meminit pgdat_init_internals(struct pglist_data *pgdat)
1354 {
1355 	int i;
1356 
1357 	pgdat_resize_init(pgdat);
1358 	pgdat_kswapd_lock_init(pgdat);
1359 
1360 	pgdat_init_split_queue(pgdat);
1361 	pgdat_init_kcompactd(pgdat);
1362 
1363 	init_waitqueue_head(&pgdat->kswapd_wait);
1364 	init_waitqueue_head(&pgdat->pfmemalloc_wait);
1365 
1366 	for (i = 0; i < NR_VMSCAN_THROTTLE; i++)
1367 		init_waitqueue_head(&pgdat->reclaim_wait[i]);
1368 
1369 	pgdat_page_ext_init(pgdat);
1370 	lruvec_init(&pgdat->__lruvec);
1371 }
1372 
1373 static void __meminit zone_init_internals(struct zone *zone, enum zone_type idx, int nid,
1374 							unsigned long remaining_pages)
1375 {
1376 	atomic_long_set(&zone->managed_pages, remaining_pages);
1377 	zone_set_nid(zone, nid);
1378 	zone->name = zone_names[idx];
1379 	zone->zone_pgdat = NODE_DATA(nid);
1380 	spin_lock_init(&zone->lock);
1381 	zone_seqlock_init(zone);
1382 	zone_pcp_init(zone);
1383 }
1384 
1385 static void __meminit zone_init_free_lists(struct zone *zone)
1386 {
1387 	unsigned int order, t;
1388 	for_each_migratetype_order(order, t) {
1389 		INIT_LIST_HEAD(&zone->free_area[order].free_list[t]);
1390 		zone->free_area[order].nr_free = 0;
1391 	}
1392 
1393 #ifdef CONFIG_UNACCEPTED_MEMORY
1394 	INIT_LIST_HEAD(&zone->unaccepted_pages);
1395 #endif
1396 }
1397 
1398 void __meminit init_currently_empty_zone(struct zone *zone,
1399 					unsigned long zone_start_pfn,
1400 					unsigned long size)
1401 {
1402 	struct pglist_data *pgdat = zone->zone_pgdat;
1403 	int zone_idx = zone_idx(zone) + 1;
1404 
1405 	if (zone_idx > pgdat->nr_zones)
1406 		pgdat->nr_zones = zone_idx;
1407 
1408 	zone->zone_start_pfn = zone_start_pfn;
1409 
1410 	mminit_dprintk(MMINIT_TRACE, "memmap_init",
1411 			"Initialising map node %d zone %lu pfns %lu -> %lu\n",
1412 			pgdat->node_id,
1413 			(unsigned long)zone_idx(zone),
1414 			zone_start_pfn, (zone_start_pfn + size));
1415 
1416 	zone_init_free_lists(zone);
1417 	zone->initialized = 1;
1418 }
1419 
1420 #ifndef CONFIG_SPARSEMEM
1421 /*
1422  * Calculate the size of the zone->blockflags rounded to an unsigned long
1423  * Start by making sure zonesize is a multiple of pageblock_order by rounding
1424  * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
1425  * round what is now in bits to nearest long in bits, then return it in
1426  * bytes.
1427  */
1428 static unsigned long __init usemap_size(unsigned long zone_start_pfn, unsigned long zonesize)
1429 {
1430 	unsigned long usemapsize;
1431 
1432 	zonesize += zone_start_pfn & (pageblock_nr_pages-1);
1433 	usemapsize = roundup(zonesize, pageblock_nr_pages);
1434 	usemapsize = usemapsize >> pageblock_order;
1435 	usemapsize *= NR_PAGEBLOCK_BITS;
1436 	usemapsize = roundup(usemapsize, BITS_PER_LONG);
1437 
1438 	return usemapsize / BITS_PER_BYTE;
1439 }
1440 
1441 static void __ref setup_usemap(struct zone *zone)
1442 {
1443 	unsigned long usemapsize = usemap_size(zone->zone_start_pfn,
1444 					       zone->spanned_pages);
1445 	zone->pageblock_flags = NULL;
1446 	if (usemapsize) {
1447 		zone->pageblock_flags =
1448 			memblock_alloc_node(usemapsize, SMP_CACHE_BYTES,
1449 					    zone_to_nid(zone));
1450 		if (!zone->pageblock_flags)
1451 			panic("Failed to allocate %ld bytes for zone %s pageblock flags on node %d\n",
1452 			      usemapsize, zone->name, zone_to_nid(zone));
1453 	}
1454 }
1455 #else
1456 static inline void setup_usemap(struct zone *zone) {}
1457 #endif /* CONFIG_SPARSEMEM */
1458 
1459 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
1460 
1461 /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
1462 void __init set_pageblock_order(void)
1463 {
1464 	unsigned int order = MAX_PAGE_ORDER;
1465 
1466 	/* Check that pageblock_nr_pages has not already been setup */
1467 	if (pageblock_order)
1468 		return;
1469 
1470 	/* Don't let pageblocks exceed the maximum allocation granularity. */
1471 	if (HPAGE_SHIFT > PAGE_SHIFT && HUGETLB_PAGE_ORDER < order)
1472 		order = HUGETLB_PAGE_ORDER;
1473 
1474 	/*
1475 	 * Assume the largest contiguous order of interest is a huge page.
1476 	 * This value may be variable depending on boot parameters on powerpc.
1477 	 */
1478 	pageblock_order = order;
1479 }
1480 #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
1481 
1482 /*
1483  * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
1484  * is unused as pageblock_order is set at compile-time. See
1485  * include/linux/pageblock-flags.h for the values of pageblock_order based on
1486  * the kernel config
1487  */
1488 void __init set_pageblock_order(void)
1489 {
1490 }
1491 
1492 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
1493 
1494 /*
1495  * Set up the zone data structures
1496  * - init pgdat internals
1497  * - init all zones belonging to this node
1498  *
1499  * NOTE: this function is only called during memory hotplug
1500  */
1501 #ifdef CONFIG_MEMORY_HOTPLUG
1502 void __ref free_area_init_core_hotplug(struct pglist_data *pgdat)
1503 {
1504 	int nid = pgdat->node_id;
1505 	enum zone_type z;
1506 	int cpu;
1507 
1508 	pgdat_init_internals(pgdat);
1509 
1510 	if (pgdat->per_cpu_nodestats == &boot_nodestats)
1511 		pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat);
1512 
1513 	/*
1514 	 * Reset the nr_zones, order and highest_zoneidx before reuse.
1515 	 * Note that kswapd will init kswapd_highest_zoneidx properly
1516 	 * when it starts in the near future.
1517 	 */
1518 	pgdat->nr_zones = 0;
1519 	pgdat->kswapd_order = 0;
1520 	pgdat->kswapd_highest_zoneidx = 0;
1521 	pgdat->node_start_pfn = 0;
1522 	pgdat->node_present_pages = 0;
1523 
1524 	for_each_online_cpu(cpu) {
1525 		struct per_cpu_nodestat *p;
1526 
1527 		p = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu);
1528 		memset(p, 0, sizeof(*p));
1529 	}
1530 
1531 	/*
1532 	 * When memory is hot-added, all the memory is in offline state. So
1533 	 * clear all zones' present_pages and managed_pages because they will
1534 	 * be updated in online_pages() and offline_pages().
1535 	 */
1536 	for (z = 0; z < MAX_NR_ZONES; z++) {
1537 		struct zone *zone = pgdat->node_zones + z;
1538 
1539 		zone->present_pages = 0;
1540 		zone_init_internals(zone, z, nid, 0);
1541 	}
1542 }
1543 #endif
1544 
1545 /*
1546  * Set up the zone data structures:
1547  *   - mark all pages reserved
1548  *   - mark all memory queues empty
1549  *   - clear the memory bitmaps
1550  *
1551  * NOTE: pgdat should get zeroed by caller.
1552  * NOTE: this function is only called during early init.
1553  */
1554 static void __init free_area_init_core(struct pglist_data *pgdat)
1555 {
1556 	enum zone_type j;
1557 	int nid = pgdat->node_id;
1558 
1559 	pgdat_init_internals(pgdat);
1560 	pgdat->per_cpu_nodestats = &boot_nodestats;
1561 
1562 	for (j = 0; j < MAX_NR_ZONES; j++) {
1563 		struct zone *zone = pgdat->node_zones + j;
1564 		unsigned long size, freesize, memmap_pages;
1565 
1566 		size = zone->spanned_pages;
1567 		freesize = zone->present_pages;
1568 
1569 		/*
1570 		 * Adjust freesize so that it accounts for how much memory
1571 		 * is used by this zone for memmap. This affects the watermark
1572 		 * and per-cpu initialisations
1573 		 */
1574 		memmap_pages = calc_memmap_size(size, freesize);
1575 		if (!is_highmem_idx(j)) {
1576 			if (freesize >= memmap_pages) {
1577 				freesize -= memmap_pages;
1578 				if (memmap_pages)
1579 					pr_debug("  %s zone: %lu pages used for memmap\n",
1580 						 zone_names[j], memmap_pages);
1581 			} else
1582 				pr_warn("  %s zone: %lu memmap pages exceeds freesize %lu\n",
1583 					zone_names[j], memmap_pages, freesize);
1584 		}
1585 
1586 		/* Account for reserved pages */
1587 		if (j == 0 && freesize > dma_reserve) {
1588 			freesize -= dma_reserve;
1589 			pr_debug("  %s zone: %lu pages reserved\n", zone_names[0], dma_reserve);
1590 		}
1591 
1592 		if (!is_highmem_idx(j))
1593 			nr_kernel_pages += freesize;
1594 		/* Charge for highmem memmap if there are enough kernel pages */
1595 		else if (nr_kernel_pages > memmap_pages * 2)
1596 			nr_kernel_pages -= memmap_pages;
1597 		nr_all_pages += freesize;
1598 
1599 		/*
1600 		 * Set an approximate value for lowmem here, it will be adjusted
1601 		 * when the bootmem allocator frees pages into the buddy system.
1602 		 * And all highmem pages will be managed by the buddy system.
1603 		 */
1604 		zone_init_internals(zone, j, nid, freesize);
1605 
1606 		if (!size)
1607 			continue;
1608 
1609 		setup_usemap(zone);
1610 		init_currently_empty_zone(zone, zone->zone_start_pfn, size);
1611 	}
1612 }
1613 
1614 void __init *memmap_alloc(phys_addr_t size, phys_addr_t align,
1615 			  phys_addr_t min_addr, int nid, bool exact_nid)
1616 {
1617 	void *ptr;
1618 
1619 	if (exact_nid)
1620 		ptr = memblock_alloc_exact_nid_raw(size, align, min_addr,
1621 						   MEMBLOCK_ALLOC_ACCESSIBLE,
1622 						   nid);
1623 	else
1624 		ptr = memblock_alloc_try_nid_raw(size, align, min_addr,
1625 						 MEMBLOCK_ALLOC_ACCESSIBLE,
1626 						 nid);
1627 
1628 	if (ptr && size > 0)
1629 		page_init_poison(ptr, size);
1630 
1631 	return ptr;
1632 }
1633 
1634 #ifdef CONFIG_FLATMEM
1635 static void __init alloc_node_mem_map(struct pglist_data *pgdat)
1636 {
1637 	unsigned long start, offset, size, end;
1638 	struct page *map;
1639 
1640 	/* Skip empty nodes */
1641 	if (!pgdat->node_spanned_pages)
1642 		return;
1643 
1644 	start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1);
1645 	offset = pgdat->node_start_pfn - start;
1646 	/*
1647 		 * The zone's endpoints aren't required to be MAX_PAGE_ORDER
1648 	 * aligned but the node_mem_map endpoints must be in order
1649 	 * for the buddy allocator to function correctly.
1650 	 */
1651 	end = ALIGN(pgdat_end_pfn(pgdat), MAX_ORDER_NR_PAGES);
1652 	size =  (end - start) * sizeof(struct page);
1653 	map = memmap_alloc(size, SMP_CACHE_BYTES, MEMBLOCK_LOW_LIMIT,
1654 			   pgdat->node_id, false);
1655 	if (!map)
1656 		panic("Failed to allocate %ld bytes for node %d memory map\n",
1657 		      size, pgdat->node_id);
1658 	pgdat->node_mem_map = map + offset;
1659 	pr_debug("%s: node %d, pgdat %08lx, node_mem_map %08lx\n",
1660 		 __func__, pgdat->node_id, (unsigned long)pgdat,
1661 		 (unsigned long)pgdat->node_mem_map);
1662 #ifndef CONFIG_NUMA
1663 	/* the global mem_map is just set as node 0's */
1664 	if (pgdat == NODE_DATA(0)) {
1665 		mem_map = NODE_DATA(0)->node_mem_map;
1666 		if (page_to_pfn(mem_map) != pgdat->node_start_pfn)
1667 			mem_map -= offset;
1668 	}
1669 #endif
1670 }
1671 #else
1672 static inline void alloc_node_mem_map(struct pglist_data *pgdat) { }
1673 #endif /* CONFIG_FLATMEM */
1674 
1675 /**
1676  * get_pfn_range_for_nid - Return the start and end page frames for a node
1677  * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
1678  * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
1679  * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
1680  *
1681  * It returns the start and end page frame of a node based on information
1682  * provided by memblock_set_node(). If called for a node
1683  * with no available memory, the start and end PFNs will be 0.
1684  */
1685 void __init get_pfn_range_for_nid(unsigned int nid,
1686 			unsigned long *start_pfn, unsigned long *end_pfn)
1687 {
1688 	unsigned long this_start_pfn, this_end_pfn;
1689 	int i;
1690 
1691 	*start_pfn = -1UL;
1692 	*end_pfn = 0;
1693 
1694 	for_each_mem_pfn_range(i, nid, &this_start_pfn, &this_end_pfn, NULL) {
1695 		*start_pfn = min(*start_pfn, this_start_pfn);
1696 		*end_pfn = max(*end_pfn, this_end_pfn);
1697 	}
1698 
1699 	if (*start_pfn == -1UL)
1700 		*start_pfn = 0;
1701 }
1702 
1703 static void __init free_area_init_node(int nid)
1704 {
1705 	pg_data_t *pgdat = NODE_DATA(nid);
1706 	unsigned long start_pfn = 0;
1707 	unsigned long end_pfn = 0;
1708 
1709 	/* pg_data_t should be reset to zero when it's allocated */
1710 	WARN_ON(pgdat->nr_zones || pgdat->kswapd_highest_zoneidx);
1711 
1712 	get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
1713 
1714 	pgdat->node_id = nid;
1715 	pgdat->node_start_pfn = start_pfn;
1716 	pgdat->per_cpu_nodestats = NULL;
1717 
1718 	if (start_pfn != end_pfn) {
1719 		pr_info("Initmem setup node %d [mem %#018Lx-%#018Lx]\n", nid,
1720 			(u64)start_pfn << PAGE_SHIFT,
1721 			end_pfn ? ((u64)end_pfn << PAGE_SHIFT) - 1 : 0);
1722 
1723 		calculate_node_totalpages(pgdat, start_pfn, end_pfn);
1724 	} else {
1725 		pr_info("Initmem setup node %d as memoryless\n", nid);
1726 
1727 		reset_memoryless_node_totalpages(pgdat);
1728 	}
1729 
1730 	alloc_node_mem_map(pgdat);
1731 	pgdat_set_deferred_range(pgdat);
1732 
1733 	free_area_init_core(pgdat);
1734 	lru_gen_init_pgdat(pgdat);
1735 }
1736 
1737 /* Any regular or high memory on that node ? */
1738 static void __init check_for_memory(pg_data_t *pgdat)
1739 {
1740 	enum zone_type zone_type;
1741 
1742 	for (zone_type = 0; zone_type <= ZONE_MOVABLE - 1; zone_type++) {
1743 		struct zone *zone = &pgdat->node_zones[zone_type];
1744 		if (populated_zone(zone)) {
1745 			if (IS_ENABLED(CONFIG_HIGHMEM))
1746 				node_set_state(pgdat->node_id, N_HIGH_MEMORY);
1747 			if (zone_type <= ZONE_NORMAL)
1748 				node_set_state(pgdat->node_id, N_NORMAL_MEMORY);
1749 			break;
1750 		}
1751 	}
1752 }
1753 
1754 #if MAX_NUMNODES > 1
1755 /*
1756  * Figure out the number of possible node ids.
1757  */
1758 void __init setup_nr_node_ids(void)
1759 {
1760 	unsigned int highest;
1761 
1762 	highest = find_last_bit(node_possible_map.bits, MAX_NUMNODES);
1763 	nr_node_ids = highest + 1;
1764 }
1765 #endif
1766 
1767 /*
1768  * Some architectures, e.g. ARC may have ZONE_HIGHMEM below ZONE_NORMAL. For
1769  * such cases we allow max_zone_pfn sorted in the descending order
1770  */
1771 static bool arch_has_descending_max_zone_pfns(void)
1772 {
1773 	return IS_ENABLED(CONFIG_ARC) && !IS_ENABLED(CONFIG_ARC_HAS_PAE40);
1774 }
1775 
1776 /**
1777  * free_area_init - Initialise all pg_data_t and zone data
1778  * @max_zone_pfn: an array of max PFNs for each zone
1779  *
1780  * This will call free_area_init_node() for each active node in the system.
1781  * Using the page ranges provided by memblock_set_node(), the size of each
1782  * zone in each node and their holes is calculated. If the maximum PFN
1783  * between two adjacent zones match, it is assumed that the zone is empty.
1784  * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
1785  * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
1786  * starts where the previous one ended. For example, ZONE_DMA32 starts
1787  * at arch_max_dma_pfn.
1788  */
1789 void __init free_area_init(unsigned long *max_zone_pfn)
1790 {
1791 	unsigned long start_pfn, end_pfn;
1792 	int i, nid, zone;
1793 	bool descending;
1794 
1795 	/* Record where the zone boundaries are */
1796 	memset(arch_zone_lowest_possible_pfn, 0,
1797 				sizeof(arch_zone_lowest_possible_pfn));
1798 	memset(arch_zone_highest_possible_pfn, 0,
1799 				sizeof(arch_zone_highest_possible_pfn));
1800 
1801 	start_pfn = PHYS_PFN(memblock_start_of_DRAM());
1802 	descending = arch_has_descending_max_zone_pfns();
1803 
1804 	for (i = 0; i < MAX_NR_ZONES; i++) {
1805 		if (descending)
1806 			zone = MAX_NR_ZONES - i - 1;
1807 		else
1808 			zone = i;
1809 
1810 		if (zone == ZONE_MOVABLE)
1811 			continue;
1812 
1813 		end_pfn = max(max_zone_pfn[zone], start_pfn);
1814 		arch_zone_lowest_possible_pfn[zone] = start_pfn;
1815 		arch_zone_highest_possible_pfn[zone] = end_pfn;
1816 
1817 		start_pfn = end_pfn;
1818 	}
1819 
1820 	/* Find the PFNs that ZONE_MOVABLE begins at in each node */
1821 	memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn));
1822 	find_zone_movable_pfns_for_nodes();
1823 
1824 	/* Print out the zone ranges */
1825 	pr_info("Zone ranges:\n");
1826 	for (i = 0; i < MAX_NR_ZONES; i++) {
1827 		if (i == ZONE_MOVABLE)
1828 			continue;
1829 		pr_info("  %-8s ", zone_names[i]);
1830 		if (arch_zone_lowest_possible_pfn[i] ==
1831 				arch_zone_highest_possible_pfn[i])
1832 			pr_cont("empty\n");
1833 		else
1834 			pr_cont("[mem %#018Lx-%#018Lx]\n",
1835 				(u64)arch_zone_lowest_possible_pfn[i]
1836 					<< PAGE_SHIFT,
1837 				((u64)arch_zone_highest_possible_pfn[i]
1838 					<< PAGE_SHIFT) - 1);
1839 	}
1840 
1841 	/* Print out the PFNs ZONE_MOVABLE begins at in each node */
1842 	pr_info("Movable zone start for each node\n");
1843 	for (i = 0; i < MAX_NUMNODES; i++) {
1844 		if (zone_movable_pfn[i])
1845 			pr_info("  Node %d: %#018Lx\n", i,
1846 			       (u64)zone_movable_pfn[i] << PAGE_SHIFT);
1847 	}
1848 
1849 	/*
1850 	 * Print out the early node map, and initialize the
1851 	 * subsection-map relative to active online memory ranges to
1852 	 * enable future "sub-section" extensions of the memory map.
1853 	 */
1854 	pr_info("Early memory node ranges\n");
1855 	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) {
1856 		pr_info("  node %3d: [mem %#018Lx-%#018Lx]\n", nid,
1857 			(u64)start_pfn << PAGE_SHIFT,
1858 			((u64)end_pfn << PAGE_SHIFT) - 1);
1859 		subsection_map_init(start_pfn, end_pfn - start_pfn);
1860 	}
1861 
1862 	/* Initialise every node */
1863 	mminit_verify_pageflags_layout();
1864 	setup_nr_node_ids();
1865 	set_pageblock_order();
1866 
1867 	for_each_node(nid) {
1868 		pg_data_t *pgdat;
1869 
1870 		if (!node_online(nid)) {
1871 			/* Allocator not initialized yet */
1872 			pgdat = arch_alloc_nodedata(nid);
1873 			if (!pgdat)
1874 				panic("Cannot allocate %zuB for node %d.\n",
1875 				       sizeof(*pgdat), nid);
1876 			arch_refresh_nodedata(nid, pgdat);
1877 			free_area_init_node(nid);
1878 
1879 			/*
1880 			 * We do not want to confuse userspace by sysfs
1881 			 * files/directories for node without any memory
1882 			 * attached to it, so this node is not marked as
1883 			 * N_MEMORY and not marked online so that no sysfs
1884 			 * hierarchy will be created via register_one_node for
1885 			 * it. The pgdat will get fully initialized by
1886 			 * hotadd_init_pgdat() when memory is hotplugged into
1887 			 * this node.
1888 			 */
1889 			continue;
1890 		}
1891 
1892 		pgdat = NODE_DATA(nid);
1893 		free_area_init_node(nid);
1894 
1895 		/* Any memory on that node */
1896 		if (pgdat->node_present_pages)
1897 			node_set_state(nid, N_MEMORY);
1898 		check_for_memory(pgdat);
1899 	}
1900 
1901 	memmap_init();
1902 
1903 	/* disable hash distribution for systems with a single node */
1904 	fixup_hashdist();
1905 }
1906 
1907 /**
1908  * node_map_pfn_alignment - determine the maximum internode alignment
1909  *
1910  * This function should be called after node map is populated and sorted.
1911  * It calculates the maximum power of two alignment which can distinguish
1912  * all the nodes.
1913  *
1914  * For example, if all nodes are 1GiB and aligned to 1GiB, the return value
1915  * would indicate 1GiB alignment with (1 << (30 - PAGE_SHIFT)).  If the
1916  * nodes are shifted by 256MiB, 256MiB.  Note that if only the last node is
1917  * shifted, 1GiB is enough and this function will indicate so.
1918  *
1919  * This is used to test whether pfn -> nid mapping of the chosen memory
1920  * model has fine enough granularity to avoid incorrect mapping for the
1921  * populated node map.
1922  *
1923  * Return: the determined alignment in pfn's.  0 if there is no alignment
1924  * requirement (single node).
1925  */
1926 unsigned long __init node_map_pfn_alignment(void)
1927 {
1928 	unsigned long accl_mask = 0, last_end = 0;
1929 	unsigned long start, end, mask;
1930 	int last_nid = NUMA_NO_NODE;
1931 	int i, nid;
1932 
1933 	for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, &nid) {
1934 		if (!start || last_nid < 0 || last_nid == nid) {
1935 			last_nid = nid;
1936 			last_end = end;
1937 			continue;
1938 		}
1939 
1940 		/*
1941 		 * Start with a mask granular enough to pin-point to the
1942 		 * start pfn and tick off bits one-by-one until it becomes
1943 		 * too coarse to separate the current node from the last.
1944 		 */
1945 		mask = ~((1 << __ffs(start)) - 1);
1946 		while (mask && last_end <= (start & (mask << 1)))
1947 			mask <<= 1;
1948 
1949 		/* accumulate all internode masks */
1950 		accl_mask |= mask;
1951 	}
1952 
1953 	/* convert mask to number of pages */
1954 	return ~accl_mask + 1;
1955 }
1956 
1957 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
1958 static void __init deferred_free_range(unsigned long pfn,
1959 				       unsigned long nr_pages)
1960 {
1961 	struct page *page;
1962 	unsigned long i;
1963 
1964 	if (!nr_pages)
1965 		return;
1966 
1967 	page = pfn_to_page(pfn);
1968 
1969 	/* Free a large naturally-aligned chunk if possible */
1970 	if (nr_pages == MAX_ORDER_NR_PAGES && IS_MAX_ORDER_ALIGNED(pfn)) {
1971 		for (i = 0; i < nr_pages; i += pageblock_nr_pages)
1972 			set_pageblock_migratetype(page + i, MIGRATE_MOVABLE);
1973 		__free_pages_core(page, MAX_PAGE_ORDER);
1974 		return;
1975 	}
1976 
1977 	/* Accept chunks smaller than MAX_PAGE_ORDER upfront */
1978 	accept_memory(PFN_PHYS(pfn), PFN_PHYS(pfn + nr_pages));
1979 
1980 	for (i = 0; i < nr_pages; i++, page++, pfn++) {
1981 		if (pageblock_aligned(pfn))
1982 			set_pageblock_migratetype(page, MIGRATE_MOVABLE);
1983 		__free_pages_core(page, 0);
1984 	}
1985 }
1986 
1987 /* Completion tracking for deferred_init_memmap() threads */
1988 static atomic_t pgdat_init_n_undone __initdata;
1989 static __initdata DECLARE_COMPLETION(pgdat_init_all_done_comp);
1990 
1991 static inline void __init pgdat_init_report_one_done(void)
1992 {
1993 	if (atomic_dec_and_test(&pgdat_init_n_undone))
1994 		complete(&pgdat_init_all_done_comp);
1995 }
1996 
1997 /*
1998  * Returns true if page needs to be initialized or freed to buddy allocator.
1999  *
2000  * We check if a current MAX_PAGE_ORDER block is valid by only checking the
2001  * validity of the head pfn.
2002  */
2003 static inline bool __init deferred_pfn_valid(unsigned long pfn)
2004 {
2005 	if (IS_MAX_ORDER_ALIGNED(pfn) && !pfn_valid(pfn))
2006 		return false;
2007 	return true;
2008 }
2009 
2010 /*
2011  * Free pages to buddy allocator. Try to free aligned pages in
2012  * MAX_ORDER_NR_PAGES sizes.
2013  */
2014 static void __init deferred_free_pages(unsigned long pfn,
2015 				       unsigned long end_pfn)
2016 {
2017 	unsigned long nr_free = 0;
2018 
2019 	for (; pfn < end_pfn; pfn++) {
2020 		if (!deferred_pfn_valid(pfn)) {
2021 			deferred_free_range(pfn - nr_free, nr_free);
2022 			nr_free = 0;
2023 		} else if (IS_MAX_ORDER_ALIGNED(pfn)) {
2024 			deferred_free_range(pfn - nr_free, nr_free);
2025 			nr_free = 1;
2026 		} else {
2027 			nr_free++;
2028 		}
2029 	}
2030 	/* Free the last block of pages to allocator */
2031 	deferred_free_range(pfn - nr_free, nr_free);
2032 }
2033 
2034 /*
2035  * Initialize struct pages.  We minimize pfn page lookups and scheduler checks
2036  * by performing it only once every MAX_ORDER_NR_PAGES.
2037  * Return number of pages initialized.
2038  */
2039 static unsigned long  __init deferred_init_pages(struct zone *zone,
2040 						 unsigned long pfn,
2041 						 unsigned long end_pfn)
2042 {
2043 	int nid = zone_to_nid(zone);
2044 	unsigned long nr_pages = 0;
2045 	int zid = zone_idx(zone);
2046 	struct page *page = NULL;
2047 
2048 	for (; pfn < end_pfn; pfn++) {
2049 		if (!deferred_pfn_valid(pfn)) {
2050 			page = NULL;
2051 			continue;
2052 		} else if (!page || IS_MAX_ORDER_ALIGNED(pfn)) {
2053 			page = pfn_to_page(pfn);
2054 		} else {
2055 			page++;
2056 		}
2057 		__init_single_page(page, pfn, zid, nid);
2058 		nr_pages++;
2059 	}
2060 	return (nr_pages);
2061 }
2062 
2063 /*
2064  * This function is meant to pre-load the iterator for the zone init.
2065  * Specifically it walks through the ranges until we are caught up to the
2066  * first_init_pfn value and exits there. If we never encounter the value we
2067  * return false indicating there are no valid ranges left.
2068  */
2069 static bool __init
2070 deferred_init_mem_pfn_range_in_zone(u64 *i, struct zone *zone,
2071 				    unsigned long *spfn, unsigned long *epfn,
2072 				    unsigned long first_init_pfn)
2073 {
2074 	u64 j;
2075 
2076 	/*
2077 	 * Start out by walking through the ranges in this zone that have
2078 	 * already been initialized. We don't need to do anything with them
2079 	 * so we just need to flush them out of the system.
2080 	 */
2081 	for_each_free_mem_pfn_range_in_zone(j, zone, spfn, epfn) {
2082 		if (*epfn <= first_init_pfn)
2083 			continue;
2084 		if (*spfn < first_init_pfn)
2085 			*spfn = first_init_pfn;
2086 		*i = j;
2087 		return true;
2088 	}
2089 
2090 	return false;
2091 }
2092 
2093 /*
2094  * Initialize and free pages. We do it in two loops: first we initialize
2095  * struct page, then free to buddy allocator, because while we are
2096  * freeing pages we can access pages that are ahead (computing buddy
2097  * page in __free_one_page()).
2098  *
2099  * In order to try and keep some memory in the cache we have the loop
2100  * broken along max page order boundaries. This way we will not cause
2101  * any issues with the buddy page computation.
2102  */
2103 static unsigned long __init
2104 deferred_init_maxorder(u64 *i, struct zone *zone, unsigned long *start_pfn,
2105 		       unsigned long *end_pfn)
2106 {
2107 	unsigned long mo_pfn = ALIGN(*start_pfn + 1, MAX_ORDER_NR_PAGES);
2108 	unsigned long spfn = *start_pfn, epfn = *end_pfn;
2109 	unsigned long nr_pages = 0;
2110 	u64 j = *i;
2111 
2112 	/* First we loop through and initialize the page values */
2113 	for_each_free_mem_pfn_range_in_zone_from(j, zone, start_pfn, end_pfn) {
2114 		unsigned long t;
2115 
2116 		if (mo_pfn <= *start_pfn)
2117 			break;
2118 
2119 		t = min(mo_pfn, *end_pfn);
2120 		nr_pages += deferred_init_pages(zone, *start_pfn, t);
2121 
2122 		if (mo_pfn < *end_pfn) {
2123 			*start_pfn = mo_pfn;
2124 			break;
2125 		}
2126 	}
2127 
2128 	/* Reset values and now loop through freeing pages as needed */
2129 	swap(j, *i);
2130 
2131 	for_each_free_mem_pfn_range_in_zone_from(j, zone, &spfn, &epfn) {
2132 		unsigned long t;
2133 
2134 		if (mo_pfn <= spfn)
2135 			break;
2136 
2137 		t = min(mo_pfn, epfn);
2138 		deferred_free_pages(spfn, t);
2139 
2140 		if (mo_pfn <= epfn)
2141 			break;
2142 	}
2143 
2144 	return nr_pages;
2145 }
2146 
2147 static void __init
2148 deferred_init_memmap_chunk(unsigned long start_pfn, unsigned long end_pfn,
2149 			   void *arg)
2150 {
2151 	unsigned long spfn, epfn;
2152 	struct zone *zone = arg;
2153 	u64 i;
2154 
2155 	deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, start_pfn);
2156 
2157 	/*
2158 	 * Initialize and free pages in MAX_PAGE_ORDER sized increments so that
2159 	 * we can avoid introducing any issues with the buddy allocator.
2160 	 */
2161 	while (spfn < end_pfn) {
2162 		deferred_init_maxorder(&i, zone, &spfn, &epfn);
2163 		cond_resched();
2164 	}
2165 }
2166 
2167 /* An arch may override for more concurrency. */
2168 __weak int __init
2169 deferred_page_init_max_threads(const struct cpumask *node_cpumask)
2170 {
2171 	return 1;
2172 }
2173 
2174 /* Initialise remaining memory on a node */
2175 static int __init deferred_init_memmap(void *data)
2176 {
2177 	pg_data_t *pgdat = data;
2178 	const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id);
2179 	unsigned long spfn = 0, epfn = 0;
2180 	unsigned long first_init_pfn, flags;
2181 	unsigned long start = jiffies;
2182 	struct zone *zone;
2183 	int zid, max_threads;
2184 	u64 i;
2185 
2186 	/* Bind memory initialisation thread to a local node if possible */
2187 	if (!cpumask_empty(cpumask))
2188 		set_cpus_allowed_ptr(current, cpumask);
2189 
2190 	pgdat_resize_lock(pgdat, &flags);
2191 	first_init_pfn = pgdat->first_deferred_pfn;
2192 	if (first_init_pfn == ULONG_MAX) {
2193 		pgdat_resize_unlock(pgdat, &flags);
2194 		pgdat_init_report_one_done();
2195 		return 0;
2196 	}
2197 
2198 	/* Sanity check boundaries */
2199 	BUG_ON(pgdat->first_deferred_pfn < pgdat->node_start_pfn);
2200 	BUG_ON(pgdat->first_deferred_pfn > pgdat_end_pfn(pgdat));
2201 	pgdat->first_deferred_pfn = ULONG_MAX;
2202 
2203 	/*
2204 	 * Once we unlock here, the zone cannot be grown anymore, thus if an
2205 	 * interrupt thread must allocate this early in boot, zone must be
2206 	 * pre-grown prior to start of deferred page initialization.
2207 	 */
2208 	pgdat_resize_unlock(pgdat, &flags);
2209 
2210 	/* Only the highest zone is deferred so find it */
2211 	for (zid = 0; zid < MAX_NR_ZONES; zid++) {
2212 		zone = pgdat->node_zones + zid;
2213 		if (first_init_pfn < zone_end_pfn(zone))
2214 			break;
2215 	}
2216 
2217 	/* If the zone is empty somebody else may have cleared out the zone */
2218 	if (!deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn,
2219 						 first_init_pfn))
2220 		goto zone_empty;
2221 
2222 	max_threads = deferred_page_init_max_threads(cpumask);
2223 
2224 	while (spfn < epfn) {
2225 		unsigned long epfn_align = ALIGN(epfn, PAGES_PER_SECTION);
2226 		struct padata_mt_job job = {
2227 			.thread_fn   = deferred_init_memmap_chunk,
2228 			.fn_arg      = zone,
2229 			.start       = spfn,
2230 			.size        = epfn_align - spfn,
2231 			.align       = PAGES_PER_SECTION,
2232 			.min_chunk   = PAGES_PER_SECTION,
2233 			.max_threads = max_threads,
2234 			.numa_aware  = false,
2235 		};
2236 
2237 		padata_do_multithreaded(&job);
2238 		deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn,
2239 						    epfn_align);
2240 	}
2241 zone_empty:
2242 	/* Sanity check that the next zone really is unpopulated */
2243 	WARN_ON(++zid < MAX_NR_ZONES && populated_zone(++zone));
2244 
2245 	pr_info("node %d deferred pages initialised in %ums\n",
2246 		pgdat->node_id, jiffies_to_msecs(jiffies - start));
2247 
2248 	pgdat_init_report_one_done();
2249 	return 0;
2250 }
2251 
2252 /*
2253  * If this zone has deferred pages, try to grow it by initializing enough
2254  * deferred pages to satisfy the allocation specified by order, rounded up to
2255  * the nearest PAGES_PER_SECTION boundary.  So we're adding memory in increments
2256  * of SECTION_SIZE bytes by initializing struct pages in increments of
2257  * PAGES_PER_SECTION * sizeof(struct page) bytes.
2258  *
2259  * Return true when zone was grown, otherwise return false. We return true even
2260  * when we grow less than requested, to let the caller decide if there are
2261  * enough pages to satisfy the allocation.
2262  *
2263  * Note: We use noinline because this function is needed only during boot, and
2264  * it is called from a __ref function _deferred_grow_zone. This way we are
2265  * making sure that it is not inlined into permanent text section.
2266  */
2267 bool __init deferred_grow_zone(struct zone *zone, unsigned int order)
2268 {
2269 	unsigned long nr_pages_needed = ALIGN(1 << order, PAGES_PER_SECTION);
2270 	pg_data_t *pgdat = zone->zone_pgdat;
2271 	unsigned long first_deferred_pfn = pgdat->first_deferred_pfn;
2272 	unsigned long spfn, epfn, flags;
2273 	unsigned long nr_pages = 0;
2274 	u64 i;
2275 
2276 	/* Only the last zone may have deferred pages */
2277 	if (zone_end_pfn(zone) != pgdat_end_pfn(pgdat))
2278 		return false;
2279 
2280 	pgdat_resize_lock(pgdat, &flags);
2281 
2282 	/*
2283 	 * If someone grew this zone while we were waiting for spinlock, return
2284 	 * true, as there might be enough pages already.
2285 	 */
2286 	if (first_deferred_pfn != pgdat->first_deferred_pfn) {
2287 		pgdat_resize_unlock(pgdat, &flags);
2288 		return true;
2289 	}
2290 
2291 	/* If the zone is empty somebody else may have cleared out the zone */
2292 	if (!deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn,
2293 						 first_deferred_pfn)) {
2294 		pgdat->first_deferred_pfn = ULONG_MAX;
2295 		pgdat_resize_unlock(pgdat, &flags);
2296 		/* Retry only once. */
2297 		return first_deferred_pfn != ULONG_MAX;
2298 	}
2299 
2300 	/*
2301 	 * Initialize and free pages in MAX_PAGE_ORDER sized increments so
2302 	 * that we can avoid introducing any issues with the buddy
2303 	 * allocator.
2304 	 */
2305 	while (spfn < epfn) {
2306 		/* update our first deferred PFN for this section */
2307 		first_deferred_pfn = spfn;
2308 
2309 		nr_pages += deferred_init_maxorder(&i, zone, &spfn, &epfn);
2310 		touch_nmi_watchdog();
2311 
2312 		/* We should only stop along section boundaries */
2313 		if ((first_deferred_pfn ^ spfn) < PAGES_PER_SECTION)
2314 			continue;
2315 
2316 		/* If our quota has been met we can stop here */
2317 		if (nr_pages >= nr_pages_needed)
2318 			break;
2319 	}
2320 
2321 	pgdat->first_deferred_pfn = spfn;
2322 	pgdat_resize_unlock(pgdat, &flags);
2323 
2324 	return nr_pages > 0;
2325 }
2326 
2327 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
2328 
2329 #ifdef CONFIG_CMA
2330 void __init init_cma_reserved_pageblock(struct page *page)
2331 {
2332 	unsigned i = pageblock_nr_pages;
2333 	struct page *p = page;
2334 
2335 	do {
2336 		__ClearPageReserved(p);
2337 		set_page_count(p, 0);
2338 	} while (++p, --i);
2339 
2340 	set_pageblock_migratetype(page, MIGRATE_CMA);
2341 	set_page_refcounted(page);
2342 	__free_pages(page, pageblock_order);
2343 
2344 	adjust_managed_page_count(page, pageblock_nr_pages);
2345 	page_zone(page)->cma_pages += pageblock_nr_pages;
2346 }
2347 #endif
2348 
2349 void set_zone_contiguous(struct zone *zone)
2350 {
2351 	unsigned long block_start_pfn = zone->zone_start_pfn;
2352 	unsigned long block_end_pfn;
2353 
2354 	block_end_pfn = pageblock_end_pfn(block_start_pfn);
2355 	for (; block_start_pfn < zone_end_pfn(zone);
2356 			block_start_pfn = block_end_pfn,
2357 			 block_end_pfn += pageblock_nr_pages) {
2358 
2359 		block_end_pfn = min(block_end_pfn, zone_end_pfn(zone));
2360 
2361 		if (!__pageblock_pfn_to_page(block_start_pfn,
2362 					     block_end_pfn, zone))
2363 			return;
2364 		cond_resched();
2365 	}
2366 
2367 	/* We confirm that there is no hole */
2368 	zone->contiguous = true;
2369 }
2370 
2371 void __init page_alloc_init_late(void)
2372 {
2373 	struct zone *zone;
2374 	int nid;
2375 
2376 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
2377 
2378 	/* There will be num_node_state(N_MEMORY) threads */
2379 	atomic_set(&pgdat_init_n_undone, num_node_state(N_MEMORY));
2380 	for_each_node_state(nid, N_MEMORY) {
2381 		kthread_run(deferred_init_memmap, NODE_DATA(nid), "pgdatinit%d", nid);
2382 	}
2383 
2384 	/* Block until all are initialised */
2385 	wait_for_completion(&pgdat_init_all_done_comp);
2386 
2387 	/*
2388 	 * We initialized the rest of the deferred pages.  Permanently disable
2389 	 * on-demand struct page initialization.
2390 	 */
2391 	static_branch_disable(&deferred_pages);
2392 
2393 	/* Reinit limits that are based on free pages after the kernel is up */
2394 	files_maxfiles_init();
2395 #endif
2396 
2397 	buffer_init();
2398 
2399 	/* Discard memblock private memory */
2400 	memblock_discard();
2401 
2402 	for_each_node_state(nid, N_MEMORY)
2403 		shuffle_free_memory(NODE_DATA(nid));
2404 
2405 	for_each_populated_zone(zone)
2406 		set_zone_contiguous(zone);
2407 
2408 	/* Initialize page ext after all struct pages are initialized. */
2409 	if (deferred_struct_pages)
2410 		page_ext_init();
2411 
2412 	page_alloc_sysctl_init();
2413 }
2414 
2415 #ifndef __HAVE_ARCH_RESERVED_KERNEL_PAGES
2416 /*
2417  * Returns the number of pages that arch has reserved but
2418  * is not known to alloc_large_system_hash().
2419  */
2420 static unsigned long __init arch_reserved_kernel_pages(void)
2421 {
2422 	return 0;
2423 }
2424 #endif
2425 
2426 /*
2427  * Adaptive scale is meant to reduce sizes of hash tables on large memory
2428  * machines. As memory size is increased the scale is also increased but at
2429  * slower pace.  Starting from ADAPT_SCALE_BASE (64G), every time memory
2430  * quadruples the scale is increased by one, which means the size of hash table
2431  * only doubles, instead of quadrupling as well.
2432  * Because 32-bit systems cannot have large physical memory, where this scaling
2433  * makes sense, it is disabled on such platforms.
2434  */
2435 #if __BITS_PER_LONG > 32
2436 #define ADAPT_SCALE_BASE	(64ul << 30)
2437 #define ADAPT_SCALE_SHIFT	2
2438 #define ADAPT_SCALE_NPAGES	(ADAPT_SCALE_BASE >> PAGE_SHIFT)
2439 #endif
2440 
2441 /*
2442  * allocate a large system hash table from bootmem
2443  * - it is assumed that the hash table must contain an exact power-of-2
2444  *   quantity of entries
2445  * - limit is the number of hash buckets, not the total allocation size
2446  */
2447 void *__init alloc_large_system_hash(const char *tablename,
2448 				     unsigned long bucketsize,
2449 				     unsigned long numentries,
2450 				     int scale,
2451 				     int flags,
2452 				     unsigned int *_hash_shift,
2453 				     unsigned int *_hash_mask,
2454 				     unsigned long low_limit,
2455 				     unsigned long high_limit)
2456 {
2457 	unsigned long long max = high_limit;
2458 	unsigned long log2qty, size;
2459 	void *table;
2460 	gfp_t gfp_flags;
2461 	bool virt;
2462 	bool huge;
2463 
2464 	/* allow the kernel cmdline to have a say */
2465 	if (!numentries) {
2466 		/* round applicable memory size up to nearest megabyte */
2467 		numentries = nr_kernel_pages;
2468 		numentries -= arch_reserved_kernel_pages();
2469 
2470 		/* It isn't necessary when PAGE_SIZE >= 1MB */
2471 		if (PAGE_SIZE < SZ_1M)
2472 			numentries = round_up(numentries, SZ_1M / PAGE_SIZE);
2473 
2474 #if __BITS_PER_LONG > 32
2475 		if (!high_limit) {
2476 			unsigned long adapt;
2477 
2478 			for (adapt = ADAPT_SCALE_NPAGES; adapt < numentries;
2479 			     adapt <<= ADAPT_SCALE_SHIFT)
2480 				scale++;
2481 		}
2482 #endif
2483 
2484 		/* limit to 1 bucket per 2^scale bytes of low memory */
2485 		if (scale > PAGE_SHIFT)
2486 			numentries >>= (scale - PAGE_SHIFT);
2487 		else
2488 			numentries <<= (PAGE_SHIFT - scale);
2489 
2490 		if (unlikely((numentries * bucketsize) < PAGE_SIZE))
2491 			numentries = PAGE_SIZE / bucketsize;
2492 	}
2493 	numentries = roundup_pow_of_two(numentries);
2494 
2495 	/* limit allocation size to 1/16 total memory by default */
2496 	if (max == 0) {
2497 		max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4;
2498 		do_div(max, bucketsize);
2499 	}
2500 	max = min(max, 0x80000000ULL);
2501 
2502 	if (numentries < low_limit)
2503 		numentries = low_limit;
2504 	if (numentries > max)
2505 		numentries = max;
2506 
2507 	log2qty = ilog2(numentries);
2508 
2509 	gfp_flags = (flags & HASH_ZERO) ? GFP_ATOMIC | __GFP_ZERO : GFP_ATOMIC;
2510 	do {
2511 		virt = false;
2512 		size = bucketsize << log2qty;
2513 		if (flags & HASH_EARLY) {
2514 			if (flags & HASH_ZERO)
2515 				table = memblock_alloc(size, SMP_CACHE_BYTES);
2516 			else
2517 				table = memblock_alloc_raw(size,
2518 							   SMP_CACHE_BYTES);
2519 		} else if (get_order(size) > MAX_PAGE_ORDER || hashdist) {
2520 			table = vmalloc_huge(size, gfp_flags);
2521 			virt = true;
2522 			if (table)
2523 				huge = is_vm_area_hugepages(table);
2524 		} else {
2525 			/*
2526 			 * If bucketsize is not a power-of-two, we may free
2527 			 * some pages at the end of hash table which
2528 			 * alloc_pages_exact() automatically does
2529 			 */
2530 			table = alloc_pages_exact(size, gfp_flags);
2531 			kmemleak_alloc(table, size, 1, gfp_flags);
2532 		}
2533 	} while (!table && size > PAGE_SIZE && --log2qty);
2534 
2535 	if (!table)
2536 		panic("Failed to allocate %s hash table\n", tablename);
2537 
2538 	pr_info("%s hash table entries: %ld (order: %d, %lu bytes, %s)\n",
2539 		tablename, 1UL << log2qty, ilog2(size) - PAGE_SHIFT, size,
2540 		virt ? (huge ? "vmalloc hugepage" : "vmalloc") : "linear");
2541 
2542 	if (_hash_shift)
2543 		*_hash_shift = log2qty;
2544 	if (_hash_mask)
2545 		*_hash_mask = (1 << log2qty) - 1;
2546 
2547 	return table;
2548 }
2549 
2550 /**
2551  * set_dma_reserve - set the specified number of pages reserved in the first zone
2552  * @new_dma_reserve: The number of pages to mark reserved
2553  *
2554  * The per-cpu batchsize and zone watermarks are determined by managed_pages.
2555  * In the DMA zone, a significant percentage may be consumed by kernel image
2556  * and other unfreeable allocations which can skew the watermarks badly. This
2557  * function may optionally be used to account for unfreeable pages in the
2558  * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
2559  * smaller per-cpu batchsize.
2560  */
2561 void __init set_dma_reserve(unsigned long new_dma_reserve)
2562 {
2563 	dma_reserve = new_dma_reserve;
2564 }
2565 
2566 void __init memblock_free_pages(struct page *page, unsigned long pfn,
2567 							unsigned int order)
2568 {
2569 
2570 	if (IS_ENABLED(CONFIG_DEFERRED_STRUCT_PAGE_INIT)) {
2571 		int nid = early_pfn_to_nid(pfn);
2572 
2573 		if (!early_page_initialised(pfn, nid))
2574 			return;
2575 	}
2576 
2577 	if (!kmsan_memblock_free_pages(page, order)) {
2578 		/* KMSAN will take care of these pages. */
2579 		return;
2580 	}
2581 	__free_pages_core(page, order);
2582 }
2583 
2584 DEFINE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc);
2585 EXPORT_SYMBOL(init_on_alloc);
2586 
2587 DEFINE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free);
2588 EXPORT_SYMBOL(init_on_free);
2589 
2590 static bool _init_on_alloc_enabled_early __read_mostly
2591 				= IS_ENABLED(CONFIG_INIT_ON_ALLOC_DEFAULT_ON);
2592 static int __init early_init_on_alloc(char *buf)
2593 {
2594 
2595 	return kstrtobool(buf, &_init_on_alloc_enabled_early);
2596 }
2597 early_param("init_on_alloc", early_init_on_alloc);
2598 
2599 static bool _init_on_free_enabled_early __read_mostly
2600 				= IS_ENABLED(CONFIG_INIT_ON_FREE_DEFAULT_ON);
2601 static int __init early_init_on_free(char *buf)
2602 {
2603 	return kstrtobool(buf, &_init_on_free_enabled_early);
2604 }
2605 early_param("init_on_free", early_init_on_free);
2606 
2607 DEFINE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled);
2608 
2609 /*
2610  * Enable static keys related to various memory debugging and hardening options.
2611  * Some override others, and depend on early params that are evaluated in the
2612  * order of appearance. So we need to first gather the full picture of what was
2613  * enabled, and then make decisions.
2614  */
2615 static void __init mem_debugging_and_hardening_init(void)
2616 {
2617 	bool page_poisoning_requested = false;
2618 	bool want_check_pages = false;
2619 
2620 #ifdef CONFIG_PAGE_POISONING
2621 	/*
2622 	 * Page poisoning is debug page alloc for some arches. If
2623 	 * either of those options are enabled, enable poisoning.
2624 	 */
2625 	if (page_poisoning_enabled() ||
2626 	     (!IS_ENABLED(CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC) &&
2627 	      debug_pagealloc_enabled())) {
2628 		static_branch_enable(&_page_poisoning_enabled);
2629 		page_poisoning_requested = true;
2630 		want_check_pages = true;
2631 	}
2632 #endif
2633 
2634 	if ((_init_on_alloc_enabled_early || _init_on_free_enabled_early) &&
2635 	    page_poisoning_requested) {
2636 		pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, "
2637 			"will take precedence over init_on_alloc and init_on_free\n");
2638 		_init_on_alloc_enabled_early = false;
2639 		_init_on_free_enabled_early = false;
2640 	}
2641 
2642 	if (_init_on_alloc_enabled_early) {
2643 		want_check_pages = true;
2644 		static_branch_enable(&init_on_alloc);
2645 	} else {
2646 		static_branch_disable(&init_on_alloc);
2647 	}
2648 
2649 	if (_init_on_free_enabled_early) {
2650 		want_check_pages = true;
2651 		static_branch_enable(&init_on_free);
2652 	} else {
2653 		static_branch_disable(&init_on_free);
2654 	}
2655 
2656 	if (IS_ENABLED(CONFIG_KMSAN) &&
2657 	    (_init_on_alloc_enabled_early || _init_on_free_enabled_early))
2658 		pr_info("mem auto-init: please make sure init_on_alloc and init_on_free are disabled when running KMSAN\n");
2659 
2660 #ifdef CONFIG_DEBUG_PAGEALLOC
2661 	if (debug_pagealloc_enabled()) {
2662 		want_check_pages = true;
2663 		static_branch_enable(&_debug_pagealloc_enabled);
2664 
2665 		if (debug_guardpage_minorder())
2666 			static_branch_enable(&_debug_guardpage_enabled);
2667 	}
2668 #endif
2669 
2670 	/*
2671 	 * Any page debugging or hardening option also enables sanity checking
2672 	 * of struct pages being allocated or freed. With CONFIG_DEBUG_VM it's
2673 	 * enabled already.
2674 	 */
2675 	if (!IS_ENABLED(CONFIG_DEBUG_VM) && want_check_pages)
2676 		static_branch_enable(&check_pages_enabled);
2677 }
2678 
2679 /* Report memory auto-initialization states for this boot. */
2680 static void __init report_meminit(void)
2681 {
2682 	const char *stack;
2683 
2684 	if (IS_ENABLED(CONFIG_INIT_STACK_ALL_PATTERN))
2685 		stack = "all(pattern)";
2686 	else if (IS_ENABLED(CONFIG_INIT_STACK_ALL_ZERO))
2687 		stack = "all(zero)";
2688 	else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL))
2689 		stack = "byref_all(zero)";
2690 	else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF))
2691 		stack = "byref(zero)";
2692 	else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_USER))
2693 		stack = "__user(zero)";
2694 	else
2695 		stack = "off";
2696 
2697 	pr_info("mem auto-init: stack:%s, heap alloc:%s, heap free:%s\n",
2698 		stack, want_init_on_alloc(GFP_KERNEL) ? "on" : "off",
2699 		want_init_on_free() ? "on" : "off");
2700 	if (want_init_on_free())
2701 		pr_info("mem auto-init: clearing system memory may take some time...\n");
2702 }
2703 
2704 static void __init mem_init_print_info(void)
2705 {
2706 	unsigned long physpages, codesize, datasize, rosize, bss_size;
2707 	unsigned long init_code_size, init_data_size;
2708 
2709 	physpages = get_num_physpages();
2710 	codesize = _etext - _stext;
2711 	datasize = _edata - _sdata;
2712 	rosize = __end_rodata - __start_rodata;
2713 	bss_size = __bss_stop - __bss_start;
2714 	init_data_size = __init_end - __init_begin;
2715 	init_code_size = _einittext - _sinittext;
2716 
2717 	/*
2718 	 * Detect special cases and adjust section sizes accordingly:
2719 	 * 1) .init.* may be embedded into .data sections
2720 	 * 2) .init.text.* may be out of [__init_begin, __init_end],
2721 	 *    please refer to arch/tile/kernel/vmlinux.lds.S.
2722 	 * 3) .rodata.* may be embedded into .text or .data sections.
2723 	 */
2724 #define adj_init_size(start, end, size, pos, adj) \
2725 	do { \
2726 		if (&start[0] <= &pos[0] && &pos[0] < &end[0] && size > adj) \
2727 			size -= adj; \
2728 	} while (0)
2729 
2730 	adj_init_size(__init_begin, __init_end, init_data_size,
2731 		     _sinittext, init_code_size);
2732 	adj_init_size(_stext, _etext, codesize, _sinittext, init_code_size);
2733 	adj_init_size(_sdata, _edata, datasize, __init_begin, init_data_size);
2734 	adj_init_size(_stext, _etext, codesize, __start_rodata, rosize);
2735 	adj_init_size(_sdata, _edata, datasize, __start_rodata, rosize);
2736 
2737 #undef	adj_init_size
2738 
2739 	pr_info("Memory: %luK/%luK available (%luK kernel code, %luK rwdata, %luK rodata, %luK init, %luK bss, %luK reserved, %luK cma-reserved"
2740 #ifdef	CONFIG_HIGHMEM
2741 		", %luK highmem"
2742 #endif
2743 		")\n",
2744 		K(nr_free_pages()), K(physpages),
2745 		codesize / SZ_1K, datasize / SZ_1K, rosize / SZ_1K,
2746 		(init_data_size + init_code_size) / SZ_1K, bss_size / SZ_1K,
2747 		K(physpages - totalram_pages() - totalcma_pages),
2748 		K(totalcma_pages)
2749 #ifdef	CONFIG_HIGHMEM
2750 		, K(totalhigh_pages())
2751 #endif
2752 		);
2753 }
2754 
2755 /*
2756  * Set up kernel memory allocators
2757  */
2758 void __init mm_core_init(void)
2759 {
2760 	/* Initializations relying on SMP setup */
2761 	build_all_zonelists(NULL);
2762 	page_alloc_init_cpuhp();
2763 
2764 	/*
2765 	 * page_ext requires contiguous pages,
2766 	 * bigger than MAX_PAGE_ORDER unless SPARSEMEM.
2767 	 */
2768 	page_ext_init_flatmem();
2769 	mem_debugging_and_hardening_init();
2770 	kfence_alloc_pool_and_metadata();
2771 	report_meminit();
2772 	kmsan_init_shadow();
2773 	stack_depot_early_init();
2774 	mem_init();
2775 	mem_init_print_info();
2776 	kmem_cache_init();
2777 	/*
2778 	 * page_owner must be initialized after buddy is ready, and also after
2779 	 * slab is ready so that stack_depot_init() works properly
2780 	 */
2781 	page_ext_init_flatmem_late();
2782 	kmemleak_init();
2783 	ptlock_cache_init();
2784 	pgtable_cache_init();
2785 	debug_objects_mem_init();
2786 	vmalloc_init();
2787 	/* If no deferred init page_ext now, as vmap is fully initialized */
2788 	if (!deferred_struct_pages)
2789 		page_ext_init();
2790 	/* Should be run before the first non-init thread is created */
2791 	init_espfix_bsp();
2792 	/* Should be run after espfix64 is set up. */
2793 	pti_init();
2794 	kmsan_init_runtime();
2795 	mm_cache_init();
2796 }
2797