xref: /openbmc/linux/mm/mm_init.c (revision 61167ad5fecdeaa037f3df1ba354dddd5f66a1ed)
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 "internal.h"
30 #include "slab.h"
31 #include "shuffle.h"
32 
33 #include <asm/setup.h>
34 
35 #ifdef CONFIG_DEBUG_MEMORY_INIT
36 int __meminitdata mminit_loglevel;
37 
38 /* The zonelists are simply reported, validation is manual. */
39 void __init mminit_verify_zonelist(void)
40 {
41 	int nid;
42 
43 	if (mminit_loglevel < MMINIT_VERIFY)
44 		return;
45 
46 	for_each_online_node(nid) {
47 		pg_data_t *pgdat = NODE_DATA(nid);
48 		struct zone *zone;
49 		struct zoneref *z;
50 		struct zonelist *zonelist;
51 		int i, listid, zoneid;
52 
53 		BUILD_BUG_ON(MAX_ZONELISTS > 2);
54 		for (i = 0; i < MAX_ZONELISTS * MAX_NR_ZONES; i++) {
55 
56 			/* Identify the zone and nodelist */
57 			zoneid = i % MAX_NR_ZONES;
58 			listid = i / MAX_NR_ZONES;
59 			zonelist = &pgdat->node_zonelists[listid];
60 			zone = &pgdat->node_zones[zoneid];
61 			if (!populated_zone(zone))
62 				continue;
63 
64 			/* Print information about the zonelist */
65 			printk(KERN_DEBUG "mminit::zonelist %s %d:%s = ",
66 				listid > 0 ? "thisnode" : "general", nid,
67 				zone->name);
68 
69 			/* Iterate the zonelist */
70 			for_each_zone_zonelist(zone, z, zonelist, zoneid)
71 				pr_cont("%d:%s ", zone_to_nid(zone), zone->name);
72 			pr_cont("\n");
73 		}
74 	}
75 }
76 
77 void __init mminit_verify_pageflags_layout(void)
78 {
79 	int shift, width;
80 	unsigned long or_mask, add_mask;
81 
82 	shift = 8 * sizeof(unsigned long);
83 	width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH
84 		- LAST_CPUPID_SHIFT - KASAN_TAG_WIDTH - LRU_GEN_WIDTH - LRU_REFS_WIDTH;
85 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths",
86 		"Section %d Node %d Zone %d Lastcpupid %d Kasantag %d Gen %d Tier %d Flags %d\n",
87 		SECTIONS_WIDTH,
88 		NODES_WIDTH,
89 		ZONES_WIDTH,
90 		LAST_CPUPID_WIDTH,
91 		KASAN_TAG_WIDTH,
92 		LRU_GEN_WIDTH,
93 		LRU_REFS_WIDTH,
94 		NR_PAGEFLAGS);
95 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_shifts",
96 		"Section %d Node %d Zone %d Lastcpupid %d Kasantag %d\n",
97 		SECTIONS_SHIFT,
98 		NODES_SHIFT,
99 		ZONES_SHIFT,
100 		LAST_CPUPID_SHIFT,
101 		KASAN_TAG_WIDTH);
102 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_pgshifts",
103 		"Section %lu Node %lu Zone %lu Lastcpupid %lu Kasantag %lu\n",
104 		(unsigned long)SECTIONS_PGSHIFT,
105 		(unsigned long)NODES_PGSHIFT,
106 		(unsigned long)ZONES_PGSHIFT,
107 		(unsigned long)LAST_CPUPID_PGSHIFT,
108 		(unsigned long)KASAN_TAG_PGSHIFT);
109 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodezoneid",
110 		"Node/Zone ID: %lu -> %lu\n",
111 		(unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT),
112 		(unsigned long)ZONEID_PGOFF);
113 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_usage",
114 		"location: %d -> %d layout %d -> %d unused %d -> %d page-flags\n",
115 		shift, width, width, NR_PAGEFLAGS, NR_PAGEFLAGS, 0);
116 #ifdef NODE_NOT_IN_PAGE_FLAGS
117 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
118 		"Node not in page flags");
119 #endif
120 #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
121 	mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
122 		"Last cpupid not in page flags");
123 #endif
124 
125 	if (SECTIONS_WIDTH) {
126 		shift -= SECTIONS_WIDTH;
127 		BUG_ON(shift != SECTIONS_PGSHIFT);
128 	}
129 	if (NODES_WIDTH) {
130 		shift -= NODES_WIDTH;
131 		BUG_ON(shift != NODES_PGSHIFT);
132 	}
133 	if (ZONES_WIDTH) {
134 		shift -= ZONES_WIDTH;
135 		BUG_ON(shift != ZONES_PGSHIFT);
136 	}
137 
138 	/* Check for bitmask overlaps */
139 	or_mask = (ZONES_MASK << ZONES_PGSHIFT) |
140 			(NODES_MASK << NODES_PGSHIFT) |
141 			(SECTIONS_MASK << SECTIONS_PGSHIFT);
142 	add_mask = (ZONES_MASK << ZONES_PGSHIFT) +
143 			(NODES_MASK << NODES_PGSHIFT) +
144 			(SECTIONS_MASK << SECTIONS_PGSHIFT);
145 	BUG_ON(or_mask != add_mask);
146 }
147 
148 static __init int set_mminit_loglevel(char *str)
149 {
150 	get_option(&str, &mminit_loglevel);
151 	return 0;
152 }
153 early_param("mminit_loglevel", set_mminit_loglevel);
154 #endif /* CONFIG_DEBUG_MEMORY_INIT */
155 
156 struct kobject *mm_kobj;
157 EXPORT_SYMBOL_GPL(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 		for_each_mem_region(r) {
381 			if (memblock_is_mirror(r))
382 				continue;
383 
384 			nid = memblock_get_region_node(r);
385 
386 			usable_startpfn = memblock_region_memory_base_pfn(r);
387 
388 			if (usable_startpfn < PHYS_PFN(SZ_4G)) {
389 				mem_below_4gb_not_mirrored = true;
390 				continue;
391 			}
392 
393 			zone_movable_pfn[nid] = zone_movable_pfn[nid] ?
394 				min(usable_startpfn, zone_movable_pfn[nid]) :
395 				usable_startpfn;
396 		}
397 
398 		if (mem_below_4gb_not_mirrored)
399 			pr_warn("This configuration results in unmirrored kernel memory.\n");
400 
401 		goto out2;
402 	}
403 
404 	/*
405 	 * If kernelcore=nn% or movablecore=nn% was specified, calculate the
406 	 * amount of necessary memory.
407 	 */
408 	if (required_kernelcore_percent)
409 		required_kernelcore = (totalpages * 100 * required_kernelcore_percent) /
410 				       10000UL;
411 	if (required_movablecore_percent)
412 		required_movablecore = (totalpages * 100 * required_movablecore_percent) /
413 					10000UL;
414 
415 	/*
416 	 * If movablecore= was specified, calculate what size of
417 	 * kernelcore that corresponds so that memory usable for
418 	 * any allocation type is evenly spread. If both kernelcore
419 	 * and movablecore are specified, then the value of kernelcore
420 	 * will be used for required_kernelcore if it's greater than
421 	 * what movablecore would have allowed.
422 	 */
423 	if (required_movablecore) {
424 		unsigned long corepages;
425 
426 		/*
427 		 * Round-up so that ZONE_MOVABLE is at least as large as what
428 		 * was requested by the user
429 		 */
430 		required_movablecore =
431 			roundup(required_movablecore, MAX_ORDER_NR_PAGES);
432 		required_movablecore = min(totalpages, required_movablecore);
433 		corepages = totalpages - required_movablecore;
434 
435 		required_kernelcore = max(required_kernelcore, corepages);
436 	}
437 
438 	/*
439 	 * If kernelcore was not specified or kernelcore size is larger
440 	 * than totalpages, there is no ZONE_MOVABLE.
441 	 */
442 	if (!required_kernelcore || required_kernelcore >= totalpages)
443 		goto out;
444 
445 	/* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
446 	usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone];
447 
448 restart:
449 	/* Spread kernelcore memory as evenly as possible throughout nodes */
450 	kernelcore_node = required_kernelcore / usable_nodes;
451 	for_each_node_state(nid, N_MEMORY) {
452 		unsigned long start_pfn, end_pfn;
453 
454 		/*
455 		 * Recalculate kernelcore_node if the division per node
456 		 * now exceeds what is necessary to satisfy the requested
457 		 * amount of memory for the kernel
458 		 */
459 		if (required_kernelcore < kernelcore_node)
460 			kernelcore_node = required_kernelcore / usable_nodes;
461 
462 		/*
463 		 * As the map is walked, we track how much memory is usable
464 		 * by the kernel using kernelcore_remaining. When it is
465 		 * 0, the rest of the node is usable by ZONE_MOVABLE
466 		 */
467 		kernelcore_remaining = kernelcore_node;
468 
469 		/* Go through each range of PFNs within this node */
470 		for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
471 			unsigned long size_pages;
472 
473 			start_pfn = max(start_pfn, zone_movable_pfn[nid]);
474 			if (start_pfn >= end_pfn)
475 				continue;
476 
477 			/* Account for what is only usable for kernelcore */
478 			if (start_pfn < usable_startpfn) {
479 				unsigned long kernel_pages;
480 				kernel_pages = min(end_pfn, usable_startpfn)
481 								- start_pfn;
482 
483 				kernelcore_remaining -= min(kernel_pages,
484 							kernelcore_remaining);
485 				required_kernelcore -= min(kernel_pages,
486 							required_kernelcore);
487 
488 				/* Continue if range is now fully accounted */
489 				if (end_pfn <= usable_startpfn) {
490 
491 					/*
492 					 * Push zone_movable_pfn to the end so
493 					 * that if we have to rebalance
494 					 * kernelcore across nodes, we will
495 					 * not double account here
496 					 */
497 					zone_movable_pfn[nid] = end_pfn;
498 					continue;
499 				}
500 				start_pfn = usable_startpfn;
501 			}
502 
503 			/*
504 			 * The usable PFN range for ZONE_MOVABLE is from
505 			 * start_pfn->end_pfn. Calculate size_pages as the
506 			 * number of pages used as kernelcore
507 			 */
508 			size_pages = end_pfn - start_pfn;
509 			if (size_pages > kernelcore_remaining)
510 				size_pages = kernelcore_remaining;
511 			zone_movable_pfn[nid] = start_pfn + size_pages;
512 
513 			/*
514 			 * Some kernelcore has been met, update counts and
515 			 * break if the kernelcore for this node has been
516 			 * satisfied
517 			 */
518 			required_kernelcore -= min(required_kernelcore,
519 								size_pages);
520 			kernelcore_remaining -= size_pages;
521 			if (!kernelcore_remaining)
522 				break;
523 		}
524 	}
525 
526 	/*
527 	 * If there is still required_kernelcore, we do another pass with one
528 	 * less node in the count. This will push zone_movable_pfn[nid] further
529 	 * along on the nodes that still have memory until kernelcore is
530 	 * satisfied
531 	 */
532 	usable_nodes--;
533 	if (usable_nodes && required_kernelcore > usable_nodes)
534 		goto restart;
535 
536 out2:
537 	/* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
538 	for (nid = 0; nid < MAX_NUMNODES; nid++) {
539 		unsigned long start_pfn, end_pfn;
540 
541 		zone_movable_pfn[nid] =
542 			roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES);
543 
544 		get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
545 		if (zone_movable_pfn[nid] >= end_pfn)
546 			zone_movable_pfn[nid] = 0;
547 	}
548 
549 out:
550 	/* restore the node_state */
551 	node_states[N_MEMORY] = saved_node_state;
552 }
553 
554 static void __meminit __init_single_page(struct page *page, unsigned long pfn,
555 				unsigned long zone, int nid)
556 {
557 	mm_zero_struct_page(page);
558 	set_page_links(page, zone, nid, pfn);
559 	init_page_count(page);
560 	page_mapcount_reset(page);
561 	page_cpupid_reset_last(page);
562 	page_kasan_tag_reset(page);
563 
564 	INIT_LIST_HEAD(&page->lru);
565 #ifdef WANT_PAGE_VIRTUAL
566 	/* The shift won't overflow because ZONE_NORMAL is below 4G. */
567 	if (!is_highmem_idx(zone))
568 		set_page_address(page, __va(pfn << PAGE_SHIFT));
569 #endif
570 }
571 
572 #ifdef CONFIG_NUMA
573 /*
574  * During memory init memblocks map pfns to nids. The search is expensive and
575  * this caches recent lookups. The implementation of __early_pfn_to_nid
576  * treats start/end as pfns.
577  */
578 struct mminit_pfnnid_cache {
579 	unsigned long last_start;
580 	unsigned long last_end;
581 	int last_nid;
582 };
583 
584 static struct mminit_pfnnid_cache early_pfnnid_cache __meminitdata;
585 
586 /*
587  * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
588  */
589 static int __meminit __early_pfn_to_nid(unsigned long pfn,
590 					struct mminit_pfnnid_cache *state)
591 {
592 	unsigned long start_pfn, end_pfn;
593 	int nid;
594 
595 	if (state->last_start <= pfn && pfn < state->last_end)
596 		return state->last_nid;
597 
598 	nid = memblock_search_pfn_nid(pfn, &start_pfn, &end_pfn);
599 	if (nid != NUMA_NO_NODE) {
600 		state->last_start = start_pfn;
601 		state->last_end = end_pfn;
602 		state->last_nid = nid;
603 	}
604 
605 	return nid;
606 }
607 
608 int __meminit early_pfn_to_nid(unsigned long pfn)
609 {
610 	static DEFINE_SPINLOCK(early_pfn_lock);
611 	int nid;
612 
613 	spin_lock(&early_pfn_lock);
614 	nid = __early_pfn_to_nid(pfn, &early_pfnnid_cache);
615 	if (nid < 0)
616 		nid = first_online_node;
617 	spin_unlock(&early_pfn_lock);
618 
619 	return nid;
620 }
621 
622 int hashdist = HASHDIST_DEFAULT;
623 
624 static int __init set_hashdist(char *str)
625 {
626 	if (!str)
627 		return 0;
628 	hashdist = simple_strtoul(str, &str, 0);
629 	return 1;
630 }
631 __setup("hashdist=", set_hashdist);
632 
633 static inline void fixup_hashdist(void)
634 {
635 	if (num_node_state(N_MEMORY) == 1)
636 		hashdist = 0;
637 }
638 #else
639 static inline void fixup_hashdist(void) {}
640 #endif /* CONFIG_NUMA */
641 
642 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
643 static inline void pgdat_set_deferred_range(pg_data_t *pgdat)
644 {
645 	pgdat->first_deferred_pfn = ULONG_MAX;
646 }
647 
648 /* Returns true if the struct page for the pfn is initialised */
649 static inline bool __meminit early_page_initialised(unsigned long pfn, int nid)
650 {
651 	if (node_online(nid) && pfn >= NODE_DATA(nid)->first_deferred_pfn)
652 		return false;
653 
654 	return true;
655 }
656 
657 /*
658  * Returns true when the remaining initialisation should be deferred until
659  * later in the boot cycle when it can be parallelised.
660  */
661 static bool __meminit
662 defer_init(int nid, unsigned long pfn, unsigned long end_pfn)
663 {
664 	static unsigned long prev_end_pfn, nr_initialised;
665 
666 	if (early_page_ext_enabled())
667 		return false;
668 	/*
669 	 * prev_end_pfn static that contains the end of previous zone
670 	 * No need to protect because called very early in boot before smp_init.
671 	 */
672 	if (prev_end_pfn != end_pfn) {
673 		prev_end_pfn = end_pfn;
674 		nr_initialised = 0;
675 	}
676 
677 	/* Always populate low zones for address-constrained allocations */
678 	if (end_pfn < pgdat_end_pfn(NODE_DATA(nid)))
679 		return false;
680 
681 	if (NODE_DATA(nid)->first_deferred_pfn != ULONG_MAX)
682 		return true;
683 	/*
684 	 * We start only with one section of pages, more pages are added as
685 	 * needed until the rest of deferred pages are initialized.
686 	 */
687 	nr_initialised++;
688 	if ((nr_initialised > PAGES_PER_SECTION) &&
689 	    (pfn & (PAGES_PER_SECTION - 1)) == 0) {
690 		NODE_DATA(nid)->first_deferred_pfn = pfn;
691 		return true;
692 	}
693 	return false;
694 }
695 
696 static void __meminit init_reserved_page(unsigned long pfn, int nid)
697 {
698 	pg_data_t *pgdat;
699 	int zid;
700 
701 	if (early_page_initialised(pfn, nid))
702 		return;
703 
704 	pgdat = NODE_DATA(nid);
705 
706 	for (zid = 0; zid < MAX_NR_ZONES; zid++) {
707 		struct zone *zone = &pgdat->node_zones[zid];
708 
709 		if (zone_spans_pfn(zone, pfn))
710 			break;
711 	}
712 	__init_single_page(pfn_to_page(pfn), pfn, zid, nid);
713 }
714 #else
715 static inline void pgdat_set_deferred_range(pg_data_t *pgdat) {}
716 
717 static inline bool early_page_initialised(unsigned long pfn, int nid)
718 {
719 	return true;
720 }
721 
722 static inline bool defer_init(int nid, unsigned long pfn, unsigned long end_pfn)
723 {
724 	return false;
725 }
726 
727 static inline void init_reserved_page(unsigned long pfn, int nid)
728 {
729 }
730 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
731 
732 /*
733  * Initialised pages do not have PageReserved set. This function is
734  * called for each range allocated by the bootmem allocator and
735  * marks the pages PageReserved. The remaining valid pages are later
736  * sent to the buddy page allocator.
737  */
738 void __meminit reserve_bootmem_region(phys_addr_t start,
739 				      phys_addr_t end, int nid)
740 {
741 	unsigned long start_pfn = PFN_DOWN(start);
742 	unsigned long end_pfn = PFN_UP(end);
743 
744 	for (; start_pfn < end_pfn; start_pfn++) {
745 		if (pfn_valid(start_pfn)) {
746 			struct page *page = pfn_to_page(start_pfn);
747 
748 			init_reserved_page(start_pfn, nid);
749 
750 			/* Avoid false-positive PageTail() */
751 			INIT_LIST_HEAD(&page->lru);
752 
753 			/*
754 			 * no need for atomic set_bit because the struct
755 			 * page is not visible yet so nobody should
756 			 * access it yet.
757 			 */
758 			__SetPageReserved(page);
759 		}
760 	}
761 }
762 
763 /* If zone is ZONE_MOVABLE but memory is mirrored, it is an overlapped init */
764 static bool __meminit
765 overlap_memmap_init(unsigned long zone, unsigned long *pfn)
766 {
767 	static struct memblock_region *r;
768 
769 	if (mirrored_kernelcore && zone == ZONE_MOVABLE) {
770 		if (!r || *pfn >= memblock_region_memory_end_pfn(r)) {
771 			for_each_mem_region(r) {
772 				if (*pfn < memblock_region_memory_end_pfn(r))
773 					break;
774 			}
775 		}
776 		if (*pfn >= memblock_region_memory_base_pfn(r) &&
777 		    memblock_is_mirror(r)) {
778 			*pfn = memblock_region_memory_end_pfn(r);
779 			return true;
780 		}
781 	}
782 	return false;
783 }
784 
785 /*
786  * Only struct pages that correspond to ranges defined by memblock.memory
787  * are zeroed and initialized by going through __init_single_page() during
788  * memmap_init_zone_range().
789  *
790  * But, there could be struct pages that correspond to holes in
791  * memblock.memory. This can happen because of the following reasons:
792  * - physical memory bank size is not necessarily the exact multiple of the
793  *   arbitrary section size
794  * - early reserved memory may not be listed in memblock.memory
795  * - memory layouts defined with memmap= kernel parameter may not align
796  *   nicely with memmap sections
797  *
798  * Explicitly initialize those struct pages so that:
799  * - PG_Reserved is set
800  * - zone and node links point to zone and node that span the page if the
801  *   hole is in the middle of a zone
802  * - zone and node links point to adjacent zone/node if the hole falls on
803  *   the zone boundary; the pages in such holes will be prepended to the
804  *   zone/node above the hole except for the trailing pages in the last
805  *   section that will be appended to the zone/node below.
806  */
807 static void __init init_unavailable_range(unsigned long spfn,
808 					  unsigned long epfn,
809 					  int zone, int node)
810 {
811 	unsigned long pfn;
812 	u64 pgcnt = 0;
813 
814 	for (pfn = spfn; pfn < epfn; pfn++) {
815 		if (!pfn_valid(pageblock_start_pfn(pfn))) {
816 			pfn = pageblock_end_pfn(pfn) - 1;
817 			continue;
818 		}
819 		__init_single_page(pfn_to_page(pfn), pfn, zone, node);
820 		__SetPageReserved(pfn_to_page(pfn));
821 		pgcnt++;
822 	}
823 
824 	if (pgcnt)
825 		pr_info("On node %d, zone %s: %lld pages in unavailable ranges",
826 			node, zone_names[zone], pgcnt);
827 }
828 
829 /*
830  * Initially all pages are reserved - free ones are freed
831  * up by memblock_free_all() once the early boot process is
832  * done. Non-atomic initialization, single-pass.
833  *
834  * All aligned pageblocks are initialized to the specified migratetype
835  * (usually MIGRATE_MOVABLE). Besides setting the migratetype, no related
836  * zone stats (e.g., nr_isolate_pageblock) are touched.
837  */
838 void __meminit memmap_init_range(unsigned long size, int nid, unsigned long zone,
839 		unsigned long start_pfn, unsigned long zone_end_pfn,
840 		enum meminit_context context,
841 		struct vmem_altmap *altmap, int migratetype)
842 {
843 	unsigned long pfn, end_pfn = start_pfn + size;
844 	struct page *page;
845 
846 	if (highest_memmap_pfn < end_pfn - 1)
847 		highest_memmap_pfn = end_pfn - 1;
848 
849 #ifdef CONFIG_ZONE_DEVICE
850 	/*
851 	 * Honor reservation requested by the driver for this ZONE_DEVICE
852 	 * memory. We limit the total number of pages to initialize to just
853 	 * those that might contain the memory mapping. We will defer the
854 	 * ZONE_DEVICE page initialization until after we have released
855 	 * the hotplug lock.
856 	 */
857 	if (zone == ZONE_DEVICE) {
858 		if (!altmap)
859 			return;
860 
861 		if (start_pfn == altmap->base_pfn)
862 			start_pfn += altmap->reserve;
863 		end_pfn = altmap->base_pfn + vmem_altmap_offset(altmap);
864 	}
865 #endif
866 
867 	for (pfn = start_pfn; pfn < end_pfn; ) {
868 		/*
869 		 * There can be holes in boot-time mem_map[]s handed to this
870 		 * function.  They do not exist on hotplugged memory.
871 		 */
872 		if (context == MEMINIT_EARLY) {
873 			if (overlap_memmap_init(zone, &pfn))
874 				continue;
875 			if (defer_init(nid, pfn, zone_end_pfn)) {
876 				deferred_struct_pages = true;
877 				break;
878 			}
879 		}
880 
881 		page = pfn_to_page(pfn);
882 		__init_single_page(page, pfn, zone, nid);
883 		if (context == MEMINIT_HOTPLUG)
884 			__SetPageReserved(page);
885 
886 		/*
887 		 * Usually, we want to mark the pageblock MIGRATE_MOVABLE,
888 		 * such that unmovable allocations won't be scattered all
889 		 * over the place during system boot.
890 		 */
891 		if (pageblock_aligned(pfn)) {
892 			set_pageblock_migratetype(page, migratetype);
893 			cond_resched();
894 		}
895 		pfn++;
896 	}
897 }
898 
899 static void __init memmap_init_zone_range(struct zone *zone,
900 					  unsigned long start_pfn,
901 					  unsigned long end_pfn,
902 					  unsigned long *hole_pfn)
903 {
904 	unsigned long zone_start_pfn = zone->zone_start_pfn;
905 	unsigned long zone_end_pfn = zone_start_pfn + zone->spanned_pages;
906 	int nid = zone_to_nid(zone), zone_id = zone_idx(zone);
907 
908 	start_pfn = clamp(start_pfn, zone_start_pfn, zone_end_pfn);
909 	end_pfn = clamp(end_pfn, zone_start_pfn, zone_end_pfn);
910 
911 	if (start_pfn >= end_pfn)
912 		return;
913 
914 	memmap_init_range(end_pfn - start_pfn, nid, zone_id, start_pfn,
915 			  zone_end_pfn, MEMINIT_EARLY, NULL, MIGRATE_MOVABLE);
916 
917 	if (*hole_pfn < start_pfn)
918 		init_unavailable_range(*hole_pfn, start_pfn, zone_id, nid);
919 
920 	*hole_pfn = end_pfn;
921 }
922 
923 static void __init memmap_init(void)
924 {
925 	unsigned long start_pfn, end_pfn;
926 	unsigned long hole_pfn = 0;
927 	int i, j, zone_id = 0, nid;
928 
929 	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) {
930 		struct pglist_data *node = NODE_DATA(nid);
931 
932 		for (j = 0; j < MAX_NR_ZONES; j++) {
933 			struct zone *zone = node->node_zones + j;
934 
935 			if (!populated_zone(zone))
936 				continue;
937 
938 			memmap_init_zone_range(zone, start_pfn, end_pfn,
939 					       &hole_pfn);
940 			zone_id = j;
941 		}
942 	}
943 
944 #ifdef CONFIG_SPARSEMEM
945 	/*
946 	 * Initialize the memory map for hole in the range [memory_end,
947 	 * section_end].
948 	 * Append the pages in this hole to the highest zone in the last
949 	 * node.
950 	 * The call to init_unavailable_range() is outside the ifdef to
951 	 * silence the compiler warining about zone_id set but not used;
952 	 * for FLATMEM it is a nop anyway
953 	 */
954 	end_pfn = round_up(end_pfn, PAGES_PER_SECTION);
955 	if (hole_pfn < end_pfn)
956 #endif
957 		init_unavailable_range(hole_pfn, end_pfn, zone_id, nid);
958 }
959 
960 #ifdef CONFIG_ZONE_DEVICE
961 static void __ref __init_zone_device_page(struct page *page, unsigned long pfn,
962 					  unsigned long zone_idx, int nid,
963 					  struct dev_pagemap *pgmap)
964 {
965 
966 	__init_single_page(page, pfn, zone_idx, nid);
967 
968 	/*
969 	 * Mark page reserved as it will need to wait for onlining
970 	 * phase for it to be fully associated with a zone.
971 	 *
972 	 * We can use the non-atomic __set_bit operation for setting
973 	 * the flag as we are still initializing the pages.
974 	 */
975 	__SetPageReserved(page);
976 
977 	/*
978 	 * ZONE_DEVICE pages union ->lru with a ->pgmap back pointer
979 	 * and zone_device_data.  It is a bug if a ZONE_DEVICE page is
980 	 * ever freed or placed on a driver-private list.
981 	 */
982 	page->pgmap = pgmap;
983 	page->zone_device_data = NULL;
984 
985 	/*
986 	 * Mark the block movable so that blocks are reserved for
987 	 * movable at startup. This will force kernel allocations
988 	 * to reserve their blocks rather than leaking throughout
989 	 * the address space during boot when many long-lived
990 	 * kernel allocations are made.
991 	 *
992 	 * Please note that MEMINIT_HOTPLUG path doesn't clear memmap
993 	 * because this is done early in section_activate()
994 	 */
995 	if (pageblock_aligned(pfn)) {
996 		set_pageblock_migratetype(page, MIGRATE_MOVABLE);
997 		cond_resched();
998 	}
999 
1000 	/*
1001 	 * ZONE_DEVICE pages are released directly to the driver page allocator
1002 	 * which will set the page count to 1 when allocating the page.
1003 	 */
1004 	if (pgmap->type == MEMORY_DEVICE_PRIVATE ||
1005 	    pgmap->type == MEMORY_DEVICE_COHERENT)
1006 		set_page_count(page, 0);
1007 }
1008 
1009 /*
1010  * With compound page geometry and when struct pages are stored in ram most
1011  * tail pages are reused. Consequently, the amount of unique struct pages to
1012  * initialize is a lot smaller that the total amount of struct pages being
1013  * mapped. This is a paired / mild layering violation with explicit knowledge
1014  * of how the sparse_vmemmap internals handle compound pages in the lack
1015  * of an altmap. See vmemmap_populate_compound_pages().
1016  */
1017 static inline unsigned long compound_nr_pages(struct vmem_altmap *altmap,
1018 					      struct dev_pagemap *pgmap)
1019 {
1020 	if (!vmemmap_can_optimize(altmap, pgmap))
1021 		return pgmap_vmemmap_nr(pgmap);
1022 
1023 	return 2 * (PAGE_SIZE / sizeof(struct page));
1024 }
1025 
1026 static void __ref memmap_init_compound(struct page *head,
1027 				       unsigned long head_pfn,
1028 				       unsigned long zone_idx, int nid,
1029 				       struct dev_pagemap *pgmap,
1030 				       unsigned long nr_pages)
1031 {
1032 	unsigned long pfn, end_pfn = head_pfn + nr_pages;
1033 	unsigned int order = pgmap->vmemmap_shift;
1034 
1035 	__SetPageHead(head);
1036 	for (pfn = head_pfn + 1; pfn < end_pfn; pfn++) {
1037 		struct page *page = pfn_to_page(pfn);
1038 
1039 		__init_zone_device_page(page, pfn, zone_idx, nid, pgmap);
1040 		prep_compound_tail(head, pfn - head_pfn);
1041 		set_page_count(page, 0);
1042 
1043 		/*
1044 		 * The first tail page stores important compound page info.
1045 		 * Call prep_compound_head() after the first tail page has
1046 		 * been initialized, to not have the data overwritten.
1047 		 */
1048 		if (pfn == head_pfn + 1)
1049 			prep_compound_head(head, order);
1050 	}
1051 }
1052 
1053 void __ref memmap_init_zone_device(struct zone *zone,
1054 				   unsigned long start_pfn,
1055 				   unsigned long nr_pages,
1056 				   struct dev_pagemap *pgmap)
1057 {
1058 	unsigned long pfn, end_pfn = start_pfn + nr_pages;
1059 	struct pglist_data *pgdat = zone->zone_pgdat;
1060 	struct vmem_altmap *altmap = pgmap_altmap(pgmap);
1061 	unsigned int pfns_per_compound = pgmap_vmemmap_nr(pgmap);
1062 	unsigned long zone_idx = zone_idx(zone);
1063 	unsigned long start = jiffies;
1064 	int nid = pgdat->node_id;
1065 
1066 	if (WARN_ON_ONCE(!pgmap || zone_idx != ZONE_DEVICE))
1067 		return;
1068 
1069 	/*
1070 	 * The call to memmap_init should have already taken care
1071 	 * of the pages reserved for the memmap, so we can just jump to
1072 	 * the end of that region and start processing the device pages.
1073 	 */
1074 	if (altmap) {
1075 		start_pfn = altmap->base_pfn + vmem_altmap_offset(altmap);
1076 		nr_pages = end_pfn - start_pfn;
1077 	}
1078 
1079 	for (pfn = start_pfn; pfn < end_pfn; pfn += pfns_per_compound) {
1080 		struct page *page = pfn_to_page(pfn);
1081 
1082 		__init_zone_device_page(page, pfn, zone_idx, nid, pgmap);
1083 
1084 		if (pfns_per_compound == 1)
1085 			continue;
1086 
1087 		memmap_init_compound(page, pfn, zone_idx, nid, pgmap,
1088 				     compound_nr_pages(altmap, pgmap));
1089 	}
1090 
1091 	pr_debug("%s initialised %lu pages in %ums\n", __func__,
1092 		nr_pages, jiffies_to_msecs(jiffies - start));
1093 }
1094 #endif
1095 
1096 /*
1097  * The zone ranges provided by the architecture do not include ZONE_MOVABLE
1098  * because it is sized independent of architecture. Unlike the other zones,
1099  * the starting point for ZONE_MOVABLE is not fixed. It may be different
1100  * in each node depending on the size of each node and how evenly kernelcore
1101  * is distributed. This helper function adjusts the zone ranges
1102  * provided by the architecture for a given node by using the end of the
1103  * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
1104  * zones within a node are in order of monotonic increases memory addresses
1105  */
1106 static void __init adjust_zone_range_for_zone_movable(int nid,
1107 					unsigned long zone_type,
1108 					unsigned long node_start_pfn,
1109 					unsigned long node_end_pfn,
1110 					unsigned long *zone_start_pfn,
1111 					unsigned long *zone_end_pfn)
1112 {
1113 	/* Only adjust if ZONE_MOVABLE is on this node */
1114 	if (zone_movable_pfn[nid]) {
1115 		/* Size ZONE_MOVABLE */
1116 		if (zone_type == ZONE_MOVABLE) {
1117 			*zone_start_pfn = zone_movable_pfn[nid];
1118 			*zone_end_pfn = min(node_end_pfn,
1119 				arch_zone_highest_possible_pfn[movable_zone]);
1120 
1121 		/* Adjust for ZONE_MOVABLE starting within this range */
1122 		} else if (!mirrored_kernelcore &&
1123 			*zone_start_pfn < zone_movable_pfn[nid] &&
1124 			*zone_end_pfn > zone_movable_pfn[nid]) {
1125 			*zone_end_pfn = zone_movable_pfn[nid];
1126 
1127 		/* Check if this whole range is within ZONE_MOVABLE */
1128 		} else if (*zone_start_pfn >= zone_movable_pfn[nid])
1129 			*zone_start_pfn = *zone_end_pfn;
1130 	}
1131 }
1132 
1133 /*
1134  * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
1135  * then all holes in the requested range will be accounted for.
1136  */
1137 unsigned long __init __absent_pages_in_range(int nid,
1138 				unsigned long range_start_pfn,
1139 				unsigned long range_end_pfn)
1140 {
1141 	unsigned long nr_absent = range_end_pfn - range_start_pfn;
1142 	unsigned long start_pfn, end_pfn;
1143 	int i;
1144 
1145 	for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
1146 		start_pfn = clamp(start_pfn, range_start_pfn, range_end_pfn);
1147 		end_pfn = clamp(end_pfn, range_start_pfn, range_end_pfn);
1148 		nr_absent -= end_pfn - start_pfn;
1149 	}
1150 	return nr_absent;
1151 }
1152 
1153 /**
1154  * absent_pages_in_range - Return number of page frames in holes within a range
1155  * @start_pfn: The start PFN to start searching for holes
1156  * @end_pfn: The end PFN to stop searching for holes
1157  *
1158  * Return: the number of pages frames in memory holes within a range.
1159  */
1160 unsigned long __init absent_pages_in_range(unsigned long start_pfn,
1161 							unsigned long end_pfn)
1162 {
1163 	return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn);
1164 }
1165 
1166 /* Return the number of page frames in holes in a zone on a node */
1167 static unsigned long __init zone_absent_pages_in_node(int nid,
1168 					unsigned long zone_type,
1169 					unsigned long zone_start_pfn,
1170 					unsigned long zone_end_pfn)
1171 {
1172 	unsigned long nr_absent;
1173 
1174 	/* zone is empty, we don't have any absent pages */
1175 	if (zone_start_pfn == zone_end_pfn)
1176 		return 0;
1177 
1178 	nr_absent = __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
1179 
1180 	/*
1181 	 * ZONE_MOVABLE handling.
1182 	 * Treat pages to be ZONE_MOVABLE in ZONE_NORMAL as absent pages
1183 	 * and vice versa.
1184 	 */
1185 	if (mirrored_kernelcore && zone_movable_pfn[nid]) {
1186 		unsigned long start_pfn, end_pfn;
1187 		struct memblock_region *r;
1188 
1189 		for_each_mem_region(r) {
1190 			start_pfn = clamp(memblock_region_memory_base_pfn(r),
1191 					  zone_start_pfn, zone_end_pfn);
1192 			end_pfn = clamp(memblock_region_memory_end_pfn(r),
1193 					zone_start_pfn, zone_end_pfn);
1194 
1195 			if (zone_type == ZONE_MOVABLE &&
1196 			    memblock_is_mirror(r))
1197 				nr_absent += end_pfn - start_pfn;
1198 
1199 			if (zone_type == ZONE_NORMAL &&
1200 			    !memblock_is_mirror(r))
1201 				nr_absent += end_pfn - start_pfn;
1202 		}
1203 	}
1204 
1205 	return nr_absent;
1206 }
1207 
1208 /*
1209  * Return the number of pages a zone spans in a node, including holes
1210  * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
1211  */
1212 static unsigned long __init zone_spanned_pages_in_node(int nid,
1213 					unsigned long zone_type,
1214 					unsigned long node_start_pfn,
1215 					unsigned long node_end_pfn,
1216 					unsigned long *zone_start_pfn,
1217 					unsigned long *zone_end_pfn)
1218 {
1219 	unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type];
1220 	unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type];
1221 
1222 	/* Get the start and end of the zone */
1223 	*zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high);
1224 	*zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high);
1225 	adjust_zone_range_for_zone_movable(nid, zone_type,
1226 				node_start_pfn, node_end_pfn,
1227 				zone_start_pfn, zone_end_pfn);
1228 
1229 	/* Check that this node has pages within the zone's required range */
1230 	if (*zone_end_pfn < node_start_pfn || *zone_start_pfn > node_end_pfn)
1231 		return 0;
1232 
1233 	/* Move the zone boundaries inside the node if necessary */
1234 	*zone_end_pfn = min(*zone_end_pfn, node_end_pfn);
1235 	*zone_start_pfn = max(*zone_start_pfn, node_start_pfn);
1236 
1237 	/* Return the spanned pages */
1238 	return *zone_end_pfn - *zone_start_pfn;
1239 }
1240 
1241 static void __init reset_memoryless_node_totalpages(struct pglist_data *pgdat)
1242 {
1243 	struct zone *z;
1244 
1245 	for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++) {
1246 		z->zone_start_pfn = 0;
1247 		z->spanned_pages = 0;
1248 		z->present_pages = 0;
1249 #if defined(CONFIG_MEMORY_HOTPLUG)
1250 		z->present_early_pages = 0;
1251 #endif
1252 	}
1253 
1254 	pgdat->node_spanned_pages = 0;
1255 	pgdat->node_present_pages = 0;
1256 	pr_debug("On node %d totalpages: 0\n", pgdat->node_id);
1257 }
1258 
1259 static void __init calculate_node_totalpages(struct pglist_data *pgdat,
1260 						unsigned long node_start_pfn,
1261 						unsigned long node_end_pfn)
1262 {
1263 	unsigned long realtotalpages = 0, totalpages = 0;
1264 	enum zone_type i;
1265 
1266 	for (i = 0; i < MAX_NR_ZONES; i++) {
1267 		struct zone *zone = pgdat->node_zones + i;
1268 		unsigned long zone_start_pfn, zone_end_pfn;
1269 		unsigned long spanned, absent;
1270 		unsigned long real_size;
1271 
1272 		spanned = zone_spanned_pages_in_node(pgdat->node_id, i,
1273 						     node_start_pfn,
1274 						     node_end_pfn,
1275 						     &zone_start_pfn,
1276 						     &zone_end_pfn);
1277 		absent = zone_absent_pages_in_node(pgdat->node_id, i,
1278 						   zone_start_pfn,
1279 						   zone_end_pfn);
1280 
1281 		real_size = spanned - absent;
1282 
1283 		if (spanned)
1284 			zone->zone_start_pfn = zone_start_pfn;
1285 		else
1286 			zone->zone_start_pfn = 0;
1287 		zone->spanned_pages = spanned;
1288 		zone->present_pages = real_size;
1289 #if defined(CONFIG_MEMORY_HOTPLUG)
1290 		zone->present_early_pages = real_size;
1291 #endif
1292 
1293 		totalpages += spanned;
1294 		realtotalpages += real_size;
1295 	}
1296 
1297 	pgdat->node_spanned_pages = totalpages;
1298 	pgdat->node_present_pages = realtotalpages;
1299 	pr_debug("On node %d totalpages: %lu\n", pgdat->node_id, realtotalpages);
1300 }
1301 
1302 static unsigned long __init calc_memmap_size(unsigned long spanned_pages,
1303 						unsigned long present_pages)
1304 {
1305 	unsigned long pages = spanned_pages;
1306 
1307 	/*
1308 	 * Provide a more accurate estimation if there are holes within
1309 	 * the zone and SPARSEMEM is in use. If there are holes within the
1310 	 * zone, each populated memory region may cost us one or two extra
1311 	 * memmap pages due to alignment because memmap pages for each
1312 	 * populated regions may not be naturally aligned on page boundary.
1313 	 * So the (present_pages >> 4) heuristic is a tradeoff for that.
1314 	 */
1315 	if (spanned_pages > present_pages + (present_pages >> 4) &&
1316 	    IS_ENABLED(CONFIG_SPARSEMEM))
1317 		pages = present_pages;
1318 
1319 	return PAGE_ALIGN(pages * sizeof(struct page)) >> PAGE_SHIFT;
1320 }
1321 
1322 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1323 static void pgdat_init_split_queue(struct pglist_data *pgdat)
1324 {
1325 	struct deferred_split *ds_queue = &pgdat->deferred_split_queue;
1326 
1327 	spin_lock_init(&ds_queue->split_queue_lock);
1328 	INIT_LIST_HEAD(&ds_queue->split_queue);
1329 	ds_queue->split_queue_len = 0;
1330 }
1331 #else
1332 static void pgdat_init_split_queue(struct pglist_data *pgdat) {}
1333 #endif
1334 
1335 #ifdef CONFIG_COMPACTION
1336 static void pgdat_init_kcompactd(struct pglist_data *pgdat)
1337 {
1338 	init_waitqueue_head(&pgdat->kcompactd_wait);
1339 }
1340 #else
1341 static void pgdat_init_kcompactd(struct pglist_data *pgdat) {}
1342 #endif
1343 
1344 static void __meminit pgdat_init_internals(struct pglist_data *pgdat)
1345 {
1346 	int i;
1347 
1348 	pgdat_resize_init(pgdat);
1349 	pgdat_kswapd_lock_init(pgdat);
1350 
1351 	pgdat_init_split_queue(pgdat);
1352 	pgdat_init_kcompactd(pgdat);
1353 
1354 	init_waitqueue_head(&pgdat->kswapd_wait);
1355 	init_waitqueue_head(&pgdat->pfmemalloc_wait);
1356 
1357 	for (i = 0; i < NR_VMSCAN_THROTTLE; i++)
1358 		init_waitqueue_head(&pgdat->reclaim_wait[i]);
1359 
1360 	pgdat_page_ext_init(pgdat);
1361 	lruvec_init(&pgdat->__lruvec);
1362 }
1363 
1364 static void __meminit zone_init_internals(struct zone *zone, enum zone_type idx, int nid,
1365 							unsigned long remaining_pages)
1366 {
1367 	atomic_long_set(&zone->managed_pages, remaining_pages);
1368 	zone_set_nid(zone, nid);
1369 	zone->name = zone_names[idx];
1370 	zone->zone_pgdat = NODE_DATA(nid);
1371 	spin_lock_init(&zone->lock);
1372 	zone_seqlock_init(zone);
1373 	zone_pcp_init(zone);
1374 }
1375 
1376 static void __meminit zone_init_free_lists(struct zone *zone)
1377 {
1378 	unsigned int order, t;
1379 	for_each_migratetype_order(order, t) {
1380 		INIT_LIST_HEAD(&zone->free_area[order].free_list[t]);
1381 		zone->free_area[order].nr_free = 0;
1382 	}
1383 }
1384 
1385 void __meminit init_currently_empty_zone(struct zone *zone,
1386 					unsigned long zone_start_pfn,
1387 					unsigned long size)
1388 {
1389 	struct pglist_data *pgdat = zone->zone_pgdat;
1390 	int zone_idx = zone_idx(zone) + 1;
1391 
1392 	if (zone_idx > pgdat->nr_zones)
1393 		pgdat->nr_zones = zone_idx;
1394 
1395 	zone->zone_start_pfn = zone_start_pfn;
1396 
1397 	mminit_dprintk(MMINIT_TRACE, "memmap_init",
1398 			"Initialising map node %d zone %lu pfns %lu -> %lu\n",
1399 			pgdat->node_id,
1400 			(unsigned long)zone_idx(zone),
1401 			zone_start_pfn, (zone_start_pfn + size));
1402 
1403 	zone_init_free_lists(zone);
1404 	zone->initialized = 1;
1405 }
1406 
1407 #ifndef CONFIG_SPARSEMEM
1408 /*
1409  * Calculate the size of the zone->blockflags rounded to an unsigned long
1410  * Start by making sure zonesize is a multiple of pageblock_order by rounding
1411  * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
1412  * round what is now in bits to nearest long in bits, then return it in
1413  * bytes.
1414  */
1415 static unsigned long __init usemap_size(unsigned long zone_start_pfn, unsigned long zonesize)
1416 {
1417 	unsigned long usemapsize;
1418 
1419 	zonesize += zone_start_pfn & (pageblock_nr_pages-1);
1420 	usemapsize = roundup(zonesize, pageblock_nr_pages);
1421 	usemapsize = usemapsize >> pageblock_order;
1422 	usemapsize *= NR_PAGEBLOCK_BITS;
1423 	usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long));
1424 
1425 	return usemapsize / 8;
1426 }
1427 
1428 static void __ref setup_usemap(struct zone *zone)
1429 {
1430 	unsigned long usemapsize = usemap_size(zone->zone_start_pfn,
1431 					       zone->spanned_pages);
1432 	zone->pageblock_flags = NULL;
1433 	if (usemapsize) {
1434 		zone->pageblock_flags =
1435 			memblock_alloc_node(usemapsize, SMP_CACHE_BYTES,
1436 					    zone_to_nid(zone));
1437 		if (!zone->pageblock_flags)
1438 			panic("Failed to allocate %ld bytes for zone %s pageblock flags on node %d\n",
1439 			      usemapsize, zone->name, zone_to_nid(zone));
1440 	}
1441 }
1442 #else
1443 static inline void setup_usemap(struct zone *zone) {}
1444 #endif /* CONFIG_SPARSEMEM */
1445 
1446 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
1447 
1448 /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
1449 void __init set_pageblock_order(void)
1450 {
1451 	unsigned int order = MAX_ORDER;
1452 
1453 	/* Check that pageblock_nr_pages has not already been setup */
1454 	if (pageblock_order)
1455 		return;
1456 
1457 	/* Don't let pageblocks exceed the maximum allocation granularity. */
1458 	if (HPAGE_SHIFT > PAGE_SHIFT && HUGETLB_PAGE_ORDER < order)
1459 		order = HUGETLB_PAGE_ORDER;
1460 
1461 	/*
1462 	 * Assume the largest contiguous order of interest is a huge page.
1463 	 * This value may be variable depending on boot parameters on IA64 and
1464 	 * powerpc.
1465 	 */
1466 	pageblock_order = order;
1467 }
1468 #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
1469 
1470 /*
1471  * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
1472  * is unused as pageblock_order is set at compile-time. See
1473  * include/linux/pageblock-flags.h for the values of pageblock_order based on
1474  * the kernel config
1475  */
1476 void __init set_pageblock_order(void)
1477 {
1478 }
1479 
1480 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
1481 
1482 /*
1483  * Set up the zone data structures
1484  * - init pgdat internals
1485  * - init all zones belonging to this node
1486  *
1487  * NOTE: this function is only called during memory hotplug
1488  */
1489 #ifdef CONFIG_MEMORY_HOTPLUG
1490 void __ref free_area_init_core_hotplug(struct pglist_data *pgdat)
1491 {
1492 	int nid = pgdat->node_id;
1493 	enum zone_type z;
1494 	int cpu;
1495 
1496 	pgdat_init_internals(pgdat);
1497 
1498 	if (pgdat->per_cpu_nodestats == &boot_nodestats)
1499 		pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat);
1500 
1501 	/*
1502 	 * Reset the nr_zones, order and highest_zoneidx before reuse.
1503 	 * Note that kswapd will init kswapd_highest_zoneidx properly
1504 	 * when it starts in the near future.
1505 	 */
1506 	pgdat->nr_zones = 0;
1507 	pgdat->kswapd_order = 0;
1508 	pgdat->kswapd_highest_zoneidx = 0;
1509 	pgdat->node_start_pfn = 0;
1510 	pgdat->node_present_pages = 0;
1511 
1512 	for_each_online_cpu(cpu) {
1513 		struct per_cpu_nodestat *p;
1514 
1515 		p = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu);
1516 		memset(p, 0, sizeof(*p));
1517 	}
1518 
1519 	/*
1520 	 * When memory is hot-added, all the memory is in offline state. So
1521 	 * clear all zones' present_pages and managed_pages because they will
1522 	 * be updated in online_pages() and offline_pages().
1523 	 */
1524 	for (z = 0; z < MAX_NR_ZONES; z++) {
1525 		struct zone *zone = pgdat->node_zones + z;
1526 
1527 		zone->present_pages = 0;
1528 		zone_init_internals(zone, z, nid, 0);
1529 	}
1530 }
1531 #endif
1532 
1533 /*
1534  * Set up the zone data structures:
1535  *   - mark all pages reserved
1536  *   - mark all memory queues empty
1537  *   - clear the memory bitmaps
1538  *
1539  * NOTE: pgdat should get zeroed by caller.
1540  * NOTE: this function is only called during early init.
1541  */
1542 static void __init free_area_init_core(struct pglist_data *pgdat)
1543 {
1544 	enum zone_type j;
1545 	int nid = pgdat->node_id;
1546 
1547 	pgdat_init_internals(pgdat);
1548 	pgdat->per_cpu_nodestats = &boot_nodestats;
1549 
1550 	for (j = 0; j < MAX_NR_ZONES; j++) {
1551 		struct zone *zone = pgdat->node_zones + j;
1552 		unsigned long size, freesize, memmap_pages;
1553 
1554 		size = zone->spanned_pages;
1555 		freesize = zone->present_pages;
1556 
1557 		/*
1558 		 * Adjust freesize so that it accounts for how much memory
1559 		 * is used by this zone for memmap. This affects the watermark
1560 		 * and per-cpu initialisations
1561 		 */
1562 		memmap_pages = calc_memmap_size(size, freesize);
1563 		if (!is_highmem_idx(j)) {
1564 			if (freesize >= memmap_pages) {
1565 				freesize -= memmap_pages;
1566 				if (memmap_pages)
1567 					pr_debug("  %s zone: %lu pages used for memmap\n",
1568 						 zone_names[j], memmap_pages);
1569 			} else
1570 				pr_warn("  %s zone: %lu memmap pages exceeds freesize %lu\n",
1571 					zone_names[j], memmap_pages, freesize);
1572 		}
1573 
1574 		/* Account for reserved pages */
1575 		if (j == 0 && freesize > dma_reserve) {
1576 			freesize -= dma_reserve;
1577 			pr_debug("  %s zone: %lu pages reserved\n", zone_names[0], dma_reserve);
1578 		}
1579 
1580 		if (!is_highmem_idx(j))
1581 			nr_kernel_pages += freesize;
1582 		/* Charge for highmem memmap if there are enough kernel pages */
1583 		else if (nr_kernel_pages > memmap_pages * 2)
1584 			nr_kernel_pages -= memmap_pages;
1585 		nr_all_pages += freesize;
1586 
1587 		/*
1588 		 * Set an approximate value for lowmem here, it will be adjusted
1589 		 * when the bootmem allocator frees pages into the buddy system.
1590 		 * And all highmem pages will be managed by the buddy system.
1591 		 */
1592 		zone_init_internals(zone, j, nid, freesize);
1593 
1594 		if (!size)
1595 			continue;
1596 
1597 		setup_usemap(zone);
1598 		init_currently_empty_zone(zone, zone->zone_start_pfn, size);
1599 	}
1600 }
1601 
1602 void __init *memmap_alloc(phys_addr_t size, phys_addr_t align,
1603 			  phys_addr_t min_addr, int nid, bool exact_nid)
1604 {
1605 	void *ptr;
1606 
1607 	if (exact_nid)
1608 		ptr = memblock_alloc_exact_nid_raw(size, align, min_addr,
1609 						   MEMBLOCK_ALLOC_ACCESSIBLE,
1610 						   nid);
1611 	else
1612 		ptr = memblock_alloc_try_nid_raw(size, align, min_addr,
1613 						 MEMBLOCK_ALLOC_ACCESSIBLE,
1614 						 nid);
1615 
1616 	if (ptr && size > 0)
1617 		page_init_poison(ptr, size);
1618 
1619 	return ptr;
1620 }
1621 
1622 #ifdef CONFIG_FLATMEM
1623 static void __init alloc_node_mem_map(struct pglist_data *pgdat)
1624 {
1625 	unsigned long __maybe_unused start = 0;
1626 	unsigned long __maybe_unused offset = 0;
1627 
1628 	/* Skip empty nodes */
1629 	if (!pgdat->node_spanned_pages)
1630 		return;
1631 
1632 	start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1);
1633 	offset = pgdat->node_start_pfn - start;
1634 	/* ia64 gets its own node_mem_map, before this, without bootmem */
1635 	if (!pgdat->node_mem_map) {
1636 		unsigned long size, end;
1637 		struct page *map;
1638 
1639 		/*
1640 		 * The zone's endpoints aren't required to be MAX_ORDER
1641 		 * aligned but the node_mem_map endpoints must be in order
1642 		 * for the buddy allocator to function correctly.
1643 		 */
1644 		end = pgdat_end_pfn(pgdat);
1645 		end = ALIGN(end, MAX_ORDER_NR_PAGES);
1646 		size =  (end - start) * sizeof(struct page);
1647 		map = memmap_alloc(size, SMP_CACHE_BYTES, MEMBLOCK_LOW_LIMIT,
1648 				   pgdat->node_id, false);
1649 		if (!map)
1650 			panic("Failed to allocate %ld bytes for node %d memory map\n",
1651 			      size, pgdat->node_id);
1652 		pgdat->node_mem_map = map + offset;
1653 	}
1654 	pr_debug("%s: node %d, pgdat %08lx, node_mem_map %08lx\n",
1655 				__func__, pgdat->node_id, (unsigned long)pgdat,
1656 				(unsigned long)pgdat->node_mem_map);
1657 #ifndef CONFIG_NUMA
1658 	/*
1659 	 * With no DISCONTIG, the global mem_map is just set as node 0's
1660 	 */
1661 	if (pgdat == NODE_DATA(0)) {
1662 		mem_map = NODE_DATA(0)->node_mem_map;
1663 		if (page_to_pfn(mem_map) != pgdat->node_start_pfn)
1664 			mem_map -= offset;
1665 	}
1666 #endif
1667 }
1668 #else
1669 static inline void alloc_node_mem_map(struct pglist_data *pgdat) { }
1670 #endif /* CONFIG_FLATMEM */
1671 
1672 /**
1673  * get_pfn_range_for_nid - Return the start and end page frames for a node
1674  * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
1675  * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
1676  * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
1677  *
1678  * It returns the start and end page frame of a node based on information
1679  * provided by memblock_set_node(). If called for a node
1680  * with no available memory, a warning is printed and the start and end
1681  * PFNs will be 0.
1682  */
1683 void __init get_pfn_range_for_nid(unsigned int nid,
1684 			unsigned long *start_pfn, unsigned long *end_pfn)
1685 {
1686 	unsigned long this_start_pfn, this_end_pfn;
1687 	int i;
1688 
1689 	*start_pfn = -1UL;
1690 	*end_pfn = 0;
1691 
1692 	for_each_mem_pfn_range(i, nid, &this_start_pfn, &this_end_pfn, NULL) {
1693 		*start_pfn = min(*start_pfn, this_start_pfn);
1694 		*end_pfn = max(*end_pfn, this_end_pfn);
1695 	}
1696 
1697 	if (*start_pfn == -1UL)
1698 		*start_pfn = 0;
1699 }
1700 
1701 static void __init free_area_init_node(int nid)
1702 {
1703 	pg_data_t *pgdat = NODE_DATA(nid);
1704 	unsigned long start_pfn = 0;
1705 	unsigned long end_pfn = 0;
1706 
1707 	/* pg_data_t should be reset to zero when it's allocated */
1708 	WARN_ON(pgdat->nr_zones || pgdat->kswapd_highest_zoneidx);
1709 
1710 	get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
1711 
1712 	pgdat->node_id = nid;
1713 	pgdat->node_start_pfn = start_pfn;
1714 	pgdat->per_cpu_nodestats = NULL;
1715 
1716 	if (start_pfn != end_pfn) {
1717 		pr_info("Initmem setup node %d [mem %#018Lx-%#018Lx]\n", nid,
1718 			(u64)start_pfn << PAGE_SHIFT,
1719 			end_pfn ? ((u64)end_pfn << PAGE_SHIFT) - 1 : 0);
1720 
1721 		calculate_node_totalpages(pgdat, start_pfn, end_pfn);
1722 	} else {
1723 		pr_info("Initmem setup node %d as memoryless\n", nid);
1724 
1725 		reset_memoryless_node_totalpages(pgdat);
1726 	}
1727 
1728 	alloc_node_mem_map(pgdat);
1729 	pgdat_set_deferred_range(pgdat);
1730 
1731 	free_area_init_core(pgdat);
1732 	lru_gen_init_pgdat(pgdat);
1733 }
1734 
1735 /* Any regular or high memory on that node ? */
1736 static void check_for_memory(pg_data_t *pgdat)
1737 {
1738 	enum zone_type zone_type;
1739 
1740 	for (zone_type = 0; zone_type <= ZONE_MOVABLE - 1; zone_type++) {
1741 		struct zone *zone = &pgdat->node_zones[zone_type];
1742 		if (populated_zone(zone)) {
1743 			if (IS_ENABLED(CONFIG_HIGHMEM))
1744 				node_set_state(pgdat->node_id, N_HIGH_MEMORY);
1745 			if (zone_type <= ZONE_NORMAL)
1746 				node_set_state(pgdat->node_id, N_NORMAL_MEMORY);
1747 			break;
1748 		}
1749 	}
1750 }
1751 
1752 #if MAX_NUMNODES > 1
1753 /*
1754  * Figure out the number of possible node ids.
1755  */
1756 void __init setup_nr_node_ids(void)
1757 {
1758 	unsigned int highest;
1759 
1760 	highest = find_last_bit(node_possible_map.bits, MAX_NUMNODES);
1761 	nr_node_ids = highest + 1;
1762 }
1763 #endif
1764 
1765 /*
1766  * Some architectures, e.g. ARC may have ZONE_HIGHMEM below ZONE_NORMAL. For
1767  * such cases we allow max_zone_pfn sorted in the descending order
1768  */
1769 static bool arch_has_descending_max_zone_pfns(void)
1770 {
1771 	return IS_ENABLED(CONFIG_ARC) && !IS_ENABLED(CONFIG_ARC_HAS_PAE40);
1772 }
1773 
1774 /**
1775  * free_area_init - Initialise all pg_data_t and zone data
1776  * @max_zone_pfn: an array of max PFNs for each zone
1777  *
1778  * This will call free_area_init_node() for each active node in the system.
1779  * Using the page ranges provided by memblock_set_node(), the size of each
1780  * zone in each node and their holes is calculated. If the maximum PFN
1781  * between two adjacent zones match, it is assumed that the zone is empty.
1782  * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
1783  * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
1784  * starts where the previous one ended. For example, ZONE_DMA32 starts
1785  * at arch_max_dma_pfn.
1786  */
1787 void __init free_area_init(unsigned long *max_zone_pfn)
1788 {
1789 	unsigned long start_pfn, end_pfn;
1790 	int i, nid, zone;
1791 	bool descending;
1792 
1793 	/* Record where the zone boundaries are */
1794 	memset(arch_zone_lowest_possible_pfn, 0,
1795 				sizeof(arch_zone_lowest_possible_pfn));
1796 	memset(arch_zone_highest_possible_pfn, 0,
1797 				sizeof(arch_zone_highest_possible_pfn));
1798 
1799 	start_pfn = PHYS_PFN(memblock_start_of_DRAM());
1800 	descending = arch_has_descending_max_zone_pfns();
1801 
1802 	for (i = 0; i < MAX_NR_ZONES; i++) {
1803 		if (descending)
1804 			zone = MAX_NR_ZONES - i - 1;
1805 		else
1806 			zone = i;
1807 
1808 		if (zone == ZONE_MOVABLE)
1809 			continue;
1810 
1811 		end_pfn = max(max_zone_pfn[zone], start_pfn);
1812 		arch_zone_lowest_possible_pfn[zone] = start_pfn;
1813 		arch_zone_highest_possible_pfn[zone] = end_pfn;
1814 
1815 		start_pfn = end_pfn;
1816 	}
1817 
1818 	/* Find the PFNs that ZONE_MOVABLE begins at in each node */
1819 	memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn));
1820 	find_zone_movable_pfns_for_nodes();
1821 
1822 	/* Print out the zone ranges */
1823 	pr_info("Zone ranges:\n");
1824 	for (i = 0; i < MAX_NR_ZONES; i++) {
1825 		if (i == ZONE_MOVABLE)
1826 			continue;
1827 		pr_info("  %-8s ", zone_names[i]);
1828 		if (arch_zone_lowest_possible_pfn[i] ==
1829 				arch_zone_highest_possible_pfn[i])
1830 			pr_cont("empty\n");
1831 		else
1832 			pr_cont("[mem %#018Lx-%#018Lx]\n",
1833 				(u64)arch_zone_lowest_possible_pfn[i]
1834 					<< PAGE_SHIFT,
1835 				((u64)arch_zone_highest_possible_pfn[i]
1836 					<< PAGE_SHIFT) - 1);
1837 	}
1838 
1839 	/* Print out the PFNs ZONE_MOVABLE begins at in each node */
1840 	pr_info("Movable zone start for each node\n");
1841 	for (i = 0; i < MAX_NUMNODES; i++) {
1842 		if (zone_movable_pfn[i])
1843 			pr_info("  Node %d: %#018Lx\n", i,
1844 			       (u64)zone_movable_pfn[i] << PAGE_SHIFT);
1845 	}
1846 
1847 	/*
1848 	 * Print out the early node map, and initialize the
1849 	 * subsection-map relative to active online memory ranges to
1850 	 * enable future "sub-section" extensions of the memory map.
1851 	 */
1852 	pr_info("Early memory node ranges\n");
1853 	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) {
1854 		pr_info("  node %3d: [mem %#018Lx-%#018Lx]\n", nid,
1855 			(u64)start_pfn << PAGE_SHIFT,
1856 			((u64)end_pfn << PAGE_SHIFT) - 1);
1857 		subsection_map_init(start_pfn, end_pfn - start_pfn);
1858 	}
1859 
1860 	/* Initialise every node */
1861 	mminit_verify_pageflags_layout();
1862 	setup_nr_node_ids();
1863 	set_pageblock_order();
1864 
1865 	for_each_node(nid) {
1866 		pg_data_t *pgdat;
1867 
1868 		if (!node_online(nid)) {
1869 			pr_info("Initializing node %d as memoryless\n", nid);
1870 
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_ORDER);
1974 		return;
1975 	}
1976 
1977 	for (i = 0; i < nr_pages; i++, page++, pfn++) {
1978 		if (pageblock_aligned(pfn))
1979 			set_pageblock_migratetype(page, MIGRATE_MOVABLE);
1980 		__free_pages_core(page, 0);
1981 	}
1982 }
1983 
1984 /* Completion tracking for deferred_init_memmap() threads */
1985 static atomic_t pgdat_init_n_undone __initdata;
1986 static __initdata DECLARE_COMPLETION(pgdat_init_all_done_comp);
1987 
1988 static inline void __init pgdat_init_report_one_done(void)
1989 {
1990 	if (atomic_dec_and_test(&pgdat_init_n_undone))
1991 		complete(&pgdat_init_all_done_comp);
1992 }
1993 
1994 /*
1995  * Returns true if page needs to be initialized or freed to buddy allocator.
1996  *
1997  * We check if a current MAX_ORDER block is valid by only checking the validity
1998  * of the head pfn.
1999  */
2000 static inline bool __init deferred_pfn_valid(unsigned long pfn)
2001 {
2002 	if (IS_MAX_ORDER_ALIGNED(pfn) && !pfn_valid(pfn))
2003 		return false;
2004 	return true;
2005 }
2006 
2007 /*
2008  * Free pages to buddy allocator. Try to free aligned pages in
2009  * MAX_ORDER_NR_PAGES sizes.
2010  */
2011 static void __init deferred_free_pages(unsigned long pfn,
2012 				       unsigned long end_pfn)
2013 {
2014 	unsigned long nr_free = 0;
2015 
2016 	for (; pfn < end_pfn; pfn++) {
2017 		if (!deferred_pfn_valid(pfn)) {
2018 			deferred_free_range(pfn - nr_free, nr_free);
2019 			nr_free = 0;
2020 		} else if (IS_MAX_ORDER_ALIGNED(pfn)) {
2021 			deferred_free_range(pfn - nr_free, nr_free);
2022 			nr_free = 1;
2023 		} else {
2024 			nr_free++;
2025 		}
2026 	}
2027 	/* Free the last block of pages to allocator */
2028 	deferred_free_range(pfn - nr_free, nr_free);
2029 }
2030 
2031 /*
2032  * Initialize struct pages.  We minimize pfn page lookups and scheduler checks
2033  * by performing it only once every MAX_ORDER_NR_PAGES.
2034  * Return number of pages initialized.
2035  */
2036 static unsigned long  __init deferred_init_pages(struct zone *zone,
2037 						 unsigned long pfn,
2038 						 unsigned long end_pfn)
2039 {
2040 	int nid = zone_to_nid(zone);
2041 	unsigned long nr_pages = 0;
2042 	int zid = zone_idx(zone);
2043 	struct page *page = NULL;
2044 
2045 	for (; pfn < end_pfn; pfn++) {
2046 		if (!deferred_pfn_valid(pfn)) {
2047 			page = NULL;
2048 			continue;
2049 		} else if (!page || IS_MAX_ORDER_ALIGNED(pfn)) {
2050 			page = pfn_to_page(pfn);
2051 		} else {
2052 			page++;
2053 		}
2054 		__init_single_page(page, pfn, zid, nid);
2055 		nr_pages++;
2056 	}
2057 	return (nr_pages);
2058 }
2059 
2060 /*
2061  * This function is meant to pre-load the iterator for the zone init.
2062  * Specifically it walks through the ranges until we are caught up to the
2063  * first_init_pfn value and exits there. If we never encounter the value we
2064  * return false indicating there are no valid ranges left.
2065  */
2066 static bool __init
2067 deferred_init_mem_pfn_range_in_zone(u64 *i, struct zone *zone,
2068 				    unsigned long *spfn, unsigned long *epfn,
2069 				    unsigned long first_init_pfn)
2070 {
2071 	u64 j;
2072 
2073 	/*
2074 	 * Start out by walking through the ranges in this zone that have
2075 	 * already been initialized. We don't need to do anything with them
2076 	 * so we just need to flush them out of the system.
2077 	 */
2078 	for_each_free_mem_pfn_range_in_zone(j, zone, spfn, epfn) {
2079 		if (*epfn <= first_init_pfn)
2080 			continue;
2081 		if (*spfn < first_init_pfn)
2082 			*spfn = first_init_pfn;
2083 		*i = j;
2084 		return true;
2085 	}
2086 
2087 	return false;
2088 }
2089 
2090 /*
2091  * Initialize and free pages. We do it in two loops: first we initialize
2092  * struct page, then free to buddy allocator, because while we are
2093  * freeing pages we can access pages that are ahead (computing buddy
2094  * page in __free_one_page()).
2095  *
2096  * In order to try and keep some memory in the cache we have the loop
2097  * broken along max page order boundaries. This way we will not cause
2098  * any issues with the buddy page computation.
2099  */
2100 static unsigned long __init
2101 deferred_init_maxorder(u64 *i, struct zone *zone, unsigned long *start_pfn,
2102 		       unsigned long *end_pfn)
2103 {
2104 	unsigned long mo_pfn = ALIGN(*start_pfn + 1, MAX_ORDER_NR_PAGES);
2105 	unsigned long spfn = *start_pfn, epfn = *end_pfn;
2106 	unsigned long nr_pages = 0;
2107 	u64 j = *i;
2108 
2109 	/* First we loop through and initialize the page values */
2110 	for_each_free_mem_pfn_range_in_zone_from(j, zone, start_pfn, end_pfn) {
2111 		unsigned long t;
2112 
2113 		if (mo_pfn <= *start_pfn)
2114 			break;
2115 
2116 		t = min(mo_pfn, *end_pfn);
2117 		nr_pages += deferred_init_pages(zone, *start_pfn, t);
2118 
2119 		if (mo_pfn < *end_pfn) {
2120 			*start_pfn = mo_pfn;
2121 			break;
2122 		}
2123 	}
2124 
2125 	/* Reset values and now loop through freeing pages as needed */
2126 	swap(j, *i);
2127 
2128 	for_each_free_mem_pfn_range_in_zone_from(j, zone, &spfn, &epfn) {
2129 		unsigned long t;
2130 
2131 		if (mo_pfn <= spfn)
2132 			break;
2133 
2134 		t = min(mo_pfn, epfn);
2135 		deferred_free_pages(spfn, t);
2136 
2137 		if (mo_pfn <= epfn)
2138 			break;
2139 	}
2140 
2141 	return nr_pages;
2142 }
2143 
2144 static void __init
2145 deferred_init_memmap_chunk(unsigned long start_pfn, unsigned long end_pfn,
2146 			   void *arg)
2147 {
2148 	unsigned long spfn, epfn;
2149 	struct zone *zone = arg;
2150 	u64 i;
2151 
2152 	deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, start_pfn);
2153 
2154 	/*
2155 	 * Initialize and free pages in MAX_ORDER sized increments so that we
2156 	 * can avoid introducing any issues with the buddy allocator.
2157 	 */
2158 	while (spfn < end_pfn) {
2159 		deferred_init_maxorder(&i, zone, &spfn, &epfn);
2160 		cond_resched();
2161 	}
2162 }
2163 
2164 /* An arch may override for more concurrency. */
2165 __weak int __init
2166 deferred_page_init_max_threads(const struct cpumask *node_cpumask)
2167 {
2168 	return 1;
2169 }
2170 
2171 /* Initialise remaining memory on a node */
2172 static int __init deferred_init_memmap(void *data)
2173 {
2174 	pg_data_t *pgdat = data;
2175 	const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id);
2176 	unsigned long spfn = 0, epfn = 0;
2177 	unsigned long first_init_pfn, flags;
2178 	unsigned long start = jiffies;
2179 	struct zone *zone;
2180 	int zid, max_threads;
2181 	u64 i;
2182 
2183 	/* Bind memory initialisation thread to a local node if possible */
2184 	if (!cpumask_empty(cpumask))
2185 		set_cpus_allowed_ptr(current, cpumask);
2186 
2187 	pgdat_resize_lock(pgdat, &flags);
2188 	first_init_pfn = pgdat->first_deferred_pfn;
2189 	if (first_init_pfn == ULONG_MAX) {
2190 		pgdat_resize_unlock(pgdat, &flags);
2191 		pgdat_init_report_one_done();
2192 		return 0;
2193 	}
2194 
2195 	/* Sanity check boundaries */
2196 	BUG_ON(pgdat->first_deferred_pfn < pgdat->node_start_pfn);
2197 	BUG_ON(pgdat->first_deferred_pfn > pgdat_end_pfn(pgdat));
2198 	pgdat->first_deferred_pfn = ULONG_MAX;
2199 
2200 	/*
2201 	 * Once we unlock here, the zone cannot be grown anymore, thus if an
2202 	 * interrupt thread must allocate this early in boot, zone must be
2203 	 * pre-grown prior to start of deferred page initialization.
2204 	 */
2205 	pgdat_resize_unlock(pgdat, &flags);
2206 
2207 	/* Only the highest zone is deferred so find it */
2208 	for (zid = 0; zid < MAX_NR_ZONES; zid++) {
2209 		zone = pgdat->node_zones + zid;
2210 		if (first_init_pfn < zone_end_pfn(zone))
2211 			break;
2212 	}
2213 
2214 	/* If the zone is empty somebody else may have cleared out the zone */
2215 	if (!deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn,
2216 						 first_init_pfn))
2217 		goto zone_empty;
2218 
2219 	max_threads = deferred_page_init_max_threads(cpumask);
2220 
2221 	while (spfn < epfn) {
2222 		unsigned long epfn_align = ALIGN(epfn, PAGES_PER_SECTION);
2223 		struct padata_mt_job job = {
2224 			.thread_fn   = deferred_init_memmap_chunk,
2225 			.fn_arg      = zone,
2226 			.start       = spfn,
2227 			.size        = epfn_align - spfn,
2228 			.align       = PAGES_PER_SECTION,
2229 			.min_chunk   = PAGES_PER_SECTION,
2230 			.max_threads = max_threads,
2231 		};
2232 
2233 		padata_do_multithreaded(&job);
2234 		deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn,
2235 						    epfn_align);
2236 	}
2237 zone_empty:
2238 	/* Sanity check that the next zone really is unpopulated */
2239 	WARN_ON(++zid < MAX_NR_ZONES && populated_zone(++zone));
2240 
2241 	pr_info("node %d deferred pages initialised in %ums\n",
2242 		pgdat->node_id, jiffies_to_msecs(jiffies - start));
2243 
2244 	pgdat_init_report_one_done();
2245 	return 0;
2246 }
2247 
2248 /*
2249  * If this zone has deferred pages, try to grow it by initializing enough
2250  * deferred pages to satisfy the allocation specified by order, rounded up to
2251  * the nearest PAGES_PER_SECTION boundary.  So we're adding memory in increments
2252  * of SECTION_SIZE bytes by initializing struct pages in increments of
2253  * PAGES_PER_SECTION * sizeof(struct page) bytes.
2254  *
2255  * Return true when zone was grown, otherwise return false. We return true even
2256  * when we grow less than requested, to let the caller decide if there are
2257  * enough pages to satisfy the allocation.
2258  *
2259  * Note: We use noinline because this function is needed only during boot, and
2260  * it is called from a __ref function _deferred_grow_zone. This way we are
2261  * making sure that it is not inlined into permanent text section.
2262  */
2263 bool __init deferred_grow_zone(struct zone *zone, unsigned int order)
2264 {
2265 	unsigned long nr_pages_needed = ALIGN(1 << order, PAGES_PER_SECTION);
2266 	pg_data_t *pgdat = zone->zone_pgdat;
2267 	unsigned long first_deferred_pfn = pgdat->first_deferred_pfn;
2268 	unsigned long spfn, epfn, flags;
2269 	unsigned long nr_pages = 0;
2270 	u64 i;
2271 
2272 	/* Only the last zone may have deferred pages */
2273 	if (zone_end_pfn(zone) != pgdat_end_pfn(pgdat))
2274 		return false;
2275 
2276 	pgdat_resize_lock(pgdat, &flags);
2277 
2278 	/*
2279 	 * If someone grew this zone while we were waiting for spinlock, return
2280 	 * true, as there might be enough pages already.
2281 	 */
2282 	if (first_deferred_pfn != pgdat->first_deferred_pfn) {
2283 		pgdat_resize_unlock(pgdat, &flags);
2284 		return true;
2285 	}
2286 
2287 	/* If the zone is empty somebody else may have cleared out the zone */
2288 	if (!deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn,
2289 						 first_deferred_pfn)) {
2290 		pgdat->first_deferred_pfn = ULONG_MAX;
2291 		pgdat_resize_unlock(pgdat, &flags);
2292 		/* Retry only once. */
2293 		return first_deferred_pfn != ULONG_MAX;
2294 	}
2295 
2296 	/*
2297 	 * Initialize and free pages in MAX_ORDER sized increments so
2298 	 * that we can avoid introducing any issues with the buddy
2299 	 * allocator.
2300 	 */
2301 	while (spfn < epfn) {
2302 		/* update our first deferred PFN for this section */
2303 		first_deferred_pfn = spfn;
2304 
2305 		nr_pages += deferred_init_maxorder(&i, zone, &spfn, &epfn);
2306 		touch_nmi_watchdog();
2307 
2308 		/* We should only stop along section boundaries */
2309 		if ((first_deferred_pfn ^ spfn) < PAGES_PER_SECTION)
2310 			continue;
2311 
2312 		/* If our quota has been met we can stop here */
2313 		if (nr_pages >= nr_pages_needed)
2314 			break;
2315 	}
2316 
2317 	pgdat->first_deferred_pfn = spfn;
2318 	pgdat_resize_unlock(pgdat, &flags);
2319 
2320 	return nr_pages > 0;
2321 }
2322 
2323 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
2324 
2325 #ifdef CONFIG_CMA
2326 void __init init_cma_reserved_pageblock(struct page *page)
2327 {
2328 	unsigned i = pageblock_nr_pages;
2329 	struct page *p = page;
2330 
2331 	do {
2332 		__ClearPageReserved(p);
2333 		set_page_count(p, 0);
2334 	} while (++p, --i);
2335 
2336 	set_pageblock_migratetype(page, MIGRATE_CMA);
2337 	set_page_refcounted(page);
2338 	__free_pages(page, pageblock_order);
2339 
2340 	adjust_managed_page_count(page, pageblock_nr_pages);
2341 	page_zone(page)->cma_pages += pageblock_nr_pages;
2342 }
2343 #endif
2344 
2345 void set_zone_contiguous(struct zone *zone)
2346 {
2347 	unsigned long block_start_pfn = zone->zone_start_pfn;
2348 	unsigned long block_end_pfn;
2349 
2350 	block_end_pfn = pageblock_end_pfn(block_start_pfn);
2351 	for (; block_start_pfn < zone_end_pfn(zone);
2352 			block_start_pfn = block_end_pfn,
2353 			 block_end_pfn += pageblock_nr_pages) {
2354 
2355 		block_end_pfn = min(block_end_pfn, zone_end_pfn(zone));
2356 
2357 		if (!__pageblock_pfn_to_page(block_start_pfn,
2358 					     block_end_pfn, zone))
2359 			return;
2360 		cond_resched();
2361 	}
2362 
2363 	/* We confirm that there is no hole */
2364 	zone->contiguous = true;
2365 }
2366 
2367 void __init page_alloc_init_late(void)
2368 {
2369 	struct zone *zone;
2370 	int nid;
2371 
2372 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
2373 
2374 	/* There will be num_node_state(N_MEMORY) threads */
2375 	atomic_set(&pgdat_init_n_undone, num_node_state(N_MEMORY));
2376 	for_each_node_state(nid, N_MEMORY) {
2377 		kthread_run(deferred_init_memmap, NODE_DATA(nid), "pgdatinit%d", nid);
2378 	}
2379 
2380 	/* Block until all are initialised */
2381 	wait_for_completion(&pgdat_init_all_done_comp);
2382 
2383 	/*
2384 	 * We initialized the rest of the deferred pages.  Permanently disable
2385 	 * on-demand struct page initialization.
2386 	 */
2387 	static_branch_disable(&deferred_pages);
2388 
2389 	/* Reinit limits that are based on free pages after the kernel is up */
2390 	files_maxfiles_init();
2391 #endif
2392 
2393 	buffer_init();
2394 
2395 	/* Discard memblock private memory */
2396 	memblock_discard();
2397 
2398 	for_each_node_state(nid, N_MEMORY)
2399 		shuffle_free_memory(NODE_DATA(nid));
2400 
2401 	for_each_populated_zone(zone)
2402 		set_zone_contiguous(zone);
2403 
2404 	/* Initialize page ext after all struct pages are initialized. */
2405 	if (deferred_struct_pages)
2406 		page_ext_init();
2407 
2408 	page_alloc_sysctl_init();
2409 }
2410 
2411 #ifndef __HAVE_ARCH_RESERVED_KERNEL_PAGES
2412 /*
2413  * Returns the number of pages that arch has reserved but
2414  * is not known to alloc_large_system_hash().
2415  */
2416 static unsigned long __init arch_reserved_kernel_pages(void)
2417 {
2418 	return 0;
2419 }
2420 #endif
2421 
2422 /*
2423  * Adaptive scale is meant to reduce sizes of hash tables on large memory
2424  * machines. As memory size is increased the scale is also increased but at
2425  * slower pace.  Starting from ADAPT_SCALE_BASE (64G), every time memory
2426  * quadruples the scale is increased by one, which means the size of hash table
2427  * only doubles, instead of quadrupling as well.
2428  * Because 32-bit systems cannot have large physical memory, where this scaling
2429  * makes sense, it is disabled on such platforms.
2430  */
2431 #if __BITS_PER_LONG > 32
2432 #define ADAPT_SCALE_BASE	(64ul << 30)
2433 #define ADAPT_SCALE_SHIFT	2
2434 #define ADAPT_SCALE_NPAGES	(ADAPT_SCALE_BASE >> PAGE_SHIFT)
2435 #endif
2436 
2437 /*
2438  * allocate a large system hash table from bootmem
2439  * - it is assumed that the hash table must contain an exact power-of-2
2440  *   quantity of entries
2441  * - limit is the number of hash buckets, not the total allocation size
2442  */
2443 void *__init alloc_large_system_hash(const char *tablename,
2444 				     unsigned long bucketsize,
2445 				     unsigned long numentries,
2446 				     int scale,
2447 				     int flags,
2448 				     unsigned int *_hash_shift,
2449 				     unsigned int *_hash_mask,
2450 				     unsigned long low_limit,
2451 				     unsigned long high_limit)
2452 {
2453 	unsigned long long max = high_limit;
2454 	unsigned long log2qty, size;
2455 	void *table;
2456 	gfp_t gfp_flags;
2457 	bool virt;
2458 	bool huge;
2459 
2460 	/* allow the kernel cmdline to have a say */
2461 	if (!numentries) {
2462 		/* round applicable memory size up to nearest megabyte */
2463 		numentries = nr_kernel_pages;
2464 		numentries -= arch_reserved_kernel_pages();
2465 
2466 		/* It isn't necessary when PAGE_SIZE >= 1MB */
2467 		if (PAGE_SIZE < SZ_1M)
2468 			numentries = round_up(numentries, SZ_1M / PAGE_SIZE);
2469 
2470 #if __BITS_PER_LONG > 32
2471 		if (!high_limit) {
2472 			unsigned long adapt;
2473 
2474 			for (adapt = ADAPT_SCALE_NPAGES; adapt < numentries;
2475 			     adapt <<= ADAPT_SCALE_SHIFT)
2476 				scale++;
2477 		}
2478 #endif
2479 
2480 		/* limit to 1 bucket per 2^scale bytes of low memory */
2481 		if (scale > PAGE_SHIFT)
2482 			numentries >>= (scale - PAGE_SHIFT);
2483 		else
2484 			numentries <<= (PAGE_SHIFT - scale);
2485 
2486 		/* Make sure we've got at least a 0-order allocation.. */
2487 		if (unlikely(flags & HASH_SMALL)) {
2488 			/* Makes no sense without HASH_EARLY */
2489 			WARN_ON(!(flags & HASH_EARLY));
2490 			if (!(numentries >> *_hash_shift)) {
2491 				numentries = 1UL << *_hash_shift;
2492 				BUG_ON(!numentries);
2493 			}
2494 		} else if (unlikely((numentries * bucketsize) < PAGE_SIZE))
2495 			numentries = PAGE_SIZE / bucketsize;
2496 	}
2497 	numentries = roundup_pow_of_two(numentries);
2498 
2499 	/* limit allocation size to 1/16 total memory by default */
2500 	if (max == 0) {
2501 		max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4;
2502 		do_div(max, bucketsize);
2503 	}
2504 	max = min(max, 0x80000000ULL);
2505 
2506 	if (numentries < low_limit)
2507 		numentries = low_limit;
2508 	if (numentries > max)
2509 		numentries = max;
2510 
2511 	log2qty = ilog2(numentries);
2512 
2513 	gfp_flags = (flags & HASH_ZERO) ? GFP_ATOMIC | __GFP_ZERO : GFP_ATOMIC;
2514 	do {
2515 		virt = false;
2516 		size = bucketsize << log2qty;
2517 		if (flags & HASH_EARLY) {
2518 			if (flags & HASH_ZERO)
2519 				table = memblock_alloc(size, SMP_CACHE_BYTES);
2520 			else
2521 				table = memblock_alloc_raw(size,
2522 							   SMP_CACHE_BYTES);
2523 		} else if (get_order(size) > MAX_ORDER || hashdist) {
2524 			table = vmalloc_huge(size, gfp_flags);
2525 			virt = true;
2526 			if (table)
2527 				huge = is_vm_area_hugepages(table);
2528 		} else {
2529 			/*
2530 			 * If bucketsize is not a power-of-two, we may free
2531 			 * some pages at the end of hash table which
2532 			 * alloc_pages_exact() automatically does
2533 			 */
2534 			table = alloc_pages_exact(size, gfp_flags);
2535 			kmemleak_alloc(table, size, 1, gfp_flags);
2536 		}
2537 	} while (!table && size > PAGE_SIZE && --log2qty);
2538 
2539 	if (!table)
2540 		panic("Failed to allocate %s hash table\n", tablename);
2541 
2542 	pr_info("%s hash table entries: %ld (order: %d, %lu bytes, %s)\n",
2543 		tablename, 1UL << log2qty, ilog2(size) - PAGE_SHIFT, size,
2544 		virt ? (huge ? "vmalloc hugepage" : "vmalloc") : "linear");
2545 
2546 	if (_hash_shift)
2547 		*_hash_shift = log2qty;
2548 	if (_hash_mask)
2549 		*_hash_mask = (1 << log2qty) - 1;
2550 
2551 	return table;
2552 }
2553 
2554 /**
2555  * set_dma_reserve - set the specified number of pages reserved in the first zone
2556  * @new_dma_reserve: The number of pages to mark reserved
2557  *
2558  * The per-cpu batchsize and zone watermarks are determined by managed_pages.
2559  * In the DMA zone, a significant percentage may be consumed by kernel image
2560  * and other unfreeable allocations which can skew the watermarks badly. This
2561  * function may optionally be used to account for unfreeable pages in the
2562  * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
2563  * smaller per-cpu batchsize.
2564  */
2565 void __init set_dma_reserve(unsigned long new_dma_reserve)
2566 {
2567 	dma_reserve = new_dma_reserve;
2568 }
2569 
2570 void __init memblock_free_pages(struct page *page, unsigned long pfn,
2571 							unsigned int order)
2572 {
2573 
2574 	if (IS_ENABLED(CONFIG_DEFERRED_STRUCT_PAGE_INIT)) {
2575 		int nid = early_pfn_to_nid(pfn);
2576 
2577 		if (!early_page_initialised(pfn, nid))
2578 			return;
2579 	}
2580 
2581 	if (!kmsan_memblock_free_pages(page, order)) {
2582 		/* KMSAN will take care of these pages. */
2583 		return;
2584 	}
2585 	__free_pages_core(page, order);
2586 }
2587 
2588 DEFINE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc);
2589 EXPORT_SYMBOL(init_on_alloc);
2590 
2591 DEFINE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free);
2592 EXPORT_SYMBOL(init_on_free);
2593 
2594 static bool _init_on_alloc_enabled_early __read_mostly
2595 				= IS_ENABLED(CONFIG_INIT_ON_ALLOC_DEFAULT_ON);
2596 static int __init early_init_on_alloc(char *buf)
2597 {
2598 
2599 	return kstrtobool(buf, &_init_on_alloc_enabled_early);
2600 }
2601 early_param("init_on_alloc", early_init_on_alloc);
2602 
2603 static bool _init_on_free_enabled_early __read_mostly
2604 				= IS_ENABLED(CONFIG_INIT_ON_FREE_DEFAULT_ON);
2605 static int __init early_init_on_free(char *buf)
2606 {
2607 	return kstrtobool(buf, &_init_on_free_enabled_early);
2608 }
2609 early_param("init_on_free", early_init_on_free);
2610 
2611 DEFINE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled);
2612 
2613 /*
2614  * Enable static keys related to various memory debugging and hardening options.
2615  * Some override others, and depend on early params that are evaluated in the
2616  * order of appearance. So we need to first gather the full picture of what was
2617  * enabled, and then make decisions.
2618  */
2619 static void __init mem_debugging_and_hardening_init(void)
2620 {
2621 	bool page_poisoning_requested = false;
2622 	bool want_check_pages = false;
2623 
2624 #ifdef CONFIG_PAGE_POISONING
2625 	/*
2626 	 * Page poisoning is debug page alloc for some arches. If
2627 	 * either of those options are enabled, enable poisoning.
2628 	 */
2629 	if (page_poisoning_enabled() ||
2630 	     (!IS_ENABLED(CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC) &&
2631 	      debug_pagealloc_enabled())) {
2632 		static_branch_enable(&_page_poisoning_enabled);
2633 		page_poisoning_requested = true;
2634 		want_check_pages = true;
2635 	}
2636 #endif
2637 
2638 	if ((_init_on_alloc_enabled_early || _init_on_free_enabled_early) &&
2639 	    page_poisoning_requested) {
2640 		pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, "
2641 			"will take precedence over init_on_alloc and init_on_free\n");
2642 		_init_on_alloc_enabled_early = false;
2643 		_init_on_free_enabled_early = false;
2644 	}
2645 
2646 	if (_init_on_alloc_enabled_early) {
2647 		want_check_pages = true;
2648 		static_branch_enable(&init_on_alloc);
2649 	} else {
2650 		static_branch_disable(&init_on_alloc);
2651 	}
2652 
2653 	if (_init_on_free_enabled_early) {
2654 		want_check_pages = true;
2655 		static_branch_enable(&init_on_free);
2656 	} else {
2657 		static_branch_disable(&init_on_free);
2658 	}
2659 
2660 	if (IS_ENABLED(CONFIG_KMSAN) &&
2661 	    (_init_on_alloc_enabled_early || _init_on_free_enabled_early))
2662 		pr_info("mem auto-init: please make sure init_on_alloc and init_on_free are disabled when running KMSAN\n");
2663 
2664 #ifdef CONFIG_DEBUG_PAGEALLOC
2665 	if (debug_pagealloc_enabled()) {
2666 		want_check_pages = true;
2667 		static_branch_enable(&_debug_pagealloc_enabled);
2668 
2669 		if (debug_guardpage_minorder())
2670 			static_branch_enable(&_debug_guardpage_enabled);
2671 	}
2672 #endif
2673 
2674 	/*
2675 	 * Any page debugging or hardening option also enables sanity checking
2676 	 * of struct pages being allocated or freed. With CONFIG_DEBUG_VM it's
2677 	 * enabled already.
2678 	 */
2679 	if (!IS_ENABLED(CONFIG_DEBUG_VM) && want_check_pages)
2680 		static_branch_enable(&check_pages_enabled);
2681 }
2682 
2683 /* Report memory auto-initialization states for this boot. */
2684 static void __init report_meminit(void)
2685 {
2686 	const char *stack;
2687 
2688 	if (IS_ENABLED(CONFIG_INIT_STACK_ALL_PATTERN))
2689 		stack = "all(pattern)";
2690 	else if (IS_ENABLED(CONFIG_INIT_STACK_ALL_ZERO))
2691 		stack = "all(zero)";
2692 	else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL))
2693 		stack = "byref_all(zero)";
2694 	else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF))
2695 		stack = "byref(zero)";
2696 	else if (IS_ENABLED(CONFIG_GCC_PLUGIN_STRUCTLEAK_USER))
2697 		stack = "__user(zero)";
2698 	else
2699 		stack = "off";
2700 
2701 	pr_info("mem auto-init: stack:%s, heap alloc:%s, heap free:%s\n",
2702 		stack, want_init_on_alloc(GFP_KERNEL) ? "on" : "off",
2703 		want_init_on_free() ? "on" : "off");
2704 	if (want_init_on_free())
2705 		pr_info("mem auto-init: clearing system memory may take some time...\n");
2706 }
2707 
2708 static void __init mem_init_print_info(void)
2709 {
2710 	unsigned long physpages, codesize, datasize, rosize, bss_size;
2711 	unsigned long init_code_size, init_data_size;
2712 
2713 	physpages = get_num_physpages();
2714 	codesize = _etext - _stext;
2715 	datasize = _edata - _sdata;
2716 	rosize = __end_rodata - __start_rodata;
2717 	bss_size = __bss_stop - __bss_start;
2718 	init_data_size = __init_end - __init_begin;
2719 	init_code_size = _einittext - _sinittext;
2720 
2721 	/*
2722 	 * Detect special cases and adjust section sizes accordingly:
2723 	 * 1) .init.* may be embedded into .data sections
2724 	 * 2) .init.text.* may be out of [__init_begin, __init_end],
2725 	 *    please refer to arch/tile/kernel/vmlinux.lds.S.
2726 	 * 3) .rodata.* may be embedded into .text or .data sections.
2727 	 */
2728 #define adj_init_size(start, end, size, pos, adj) \
2729 	do { \
2730 		if (&start[0] <= &pos[0] && &pos[0] < &end[0] && size > adj) \
2731 			size -= adj; \
2732 	} while (0)
2733 
2734 	adj_init_size(__init_begin, __init_end, init_data_size,
2735 		     _sinittext, init_code_size);
2736 	adj_init_size(_stext, _etext, codesize, _sinittext, init_code_size);
2737 	adj_init_size(_sdata, _edata, datasize, __init_begin, init_data_size);
2738 	adj_init_size(_stext, _etext, codesize, __start_rodata, rosize);
2739 	adj_init_size(_sdata, _edata, datasize, __start_rodata, rosize);
2740 
2741 #undef	adj_init_size
2742 
2743 	pr_info("Memory: %luK/%luK available (%luK kernel code, %luK rwdata, %luK rodata, %luK init, %luK bss, %luK reserved, %luK cma-reserved"
2744 #ifdef	CONFIG_HIGHMEM
2745 		", %luK highmem"
2746 #endif
2747 		")\n",
2748 		K(nr_free_pages()), K(physpages),
2749 		codesize / SZ_1K, datasize / SZ_1K, rosize / SZ_1K,
2750 		(init_data_size + init_code_size) / SZ_1K, bss_size / SZ_1K,
2751 		K(physpages - totalram_pages() - totalcma_pages),
2752 		K(totalcma_pages)
2753 #ifdef	CONFIG_HIGHMEM
2754 		, K(totalhigh_pages())
2755 #endif
2756 		);
2757 }
2758 
2759 /*
2760  * Set up kernel memory allocators
2761  */
2762 void __init mm_core_init(void)
2763 {
2764 	/* Initializations relying on SMP setup */
2765 	build_all_zonelists(NULL);
2766 	page_alloc_init_cpuhp();
2767 
2768 	/*
2769 	 * page_ext requires contiguous pages,
2770 	 * bigger than MAX_ORDER unless SPARSEMEM.
2771 	 */
2772 	page_ext_init_flatmem();
2773 	mem_debugging_and_hardening_init();
2774 	kfence_alloc_pool();
2775 	report_meminit();
2776 	kmsan_init_shadow();
2777 	stack_depot_early_init();
2778 	mem_init();
2779 	mem_init_print_info();
2780 	kmem_cache_init();
2781 	/*
2782 	 * page_owner must be initialized after buddy is ready, and also after
2783 	 * slab is ready so that stack_depot_init() works properly
2784 	 */
2785 	page_ext_init_flatmem_late();
2786 	kmemleak_init();
2787 	ptlock_cache_init();
2788 	pgtable_cache_init();
2789 	debug_objects_mem_init();
2790 	vmalloc_init();
2791 	/* If no deferred init page_ext now, as vmap is fully initialized */
2792 	if (!deferred_struct_pages)
2793 		page_ext_init();
2794 	/* Should be run before the first non-init thread is created */
2795 	init_espfix_bsp();
2796 	/* Should be run after espfix64 is set up. */
2797 	pti_init();
2798 	kmsan_init_runtime();
2799 	mm_cache_init();
2800 }
2801