xref: /openbmc/linux/mm/memblock.c (revision 7ae5c03a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Procedures for maintaining information about logical memory blocks.
4  *
5  * Peter Bergner, IBM Corp.	June 2001.
6  * Copyright (C) 2001 Peter Bergner.
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/slab.h>
11 #include <linux/init.h>
12 #include <linux/bitops.h>
13 #include <linux/poison.h>
14 #include <linux/pfn.h>
15 #include <linux/debugfs.h>
16 #include <linux/kmemleak.h>
17 #include <linux/seq_file.h>
18 #include <linux/memblock.h>
19 
20 #include <asm/sections.h>
21 #include <linux/io.h>
22 
23 #include "internal.h"
24 
25 #define INIT_MEMBLOCK_REGIONS			128
26 #define INIT_PHYSMEM_REGIONS			4
27 
28 #ifndef INIT_MEMBLOCK_RESERVED_REGIONS
29 # define INIT_MEMBLOCK_RESERVED_REGIONS		INIT_MEMBLOCK_REGIONS
30 #endif
31 
32 #ifndef INIT_MEMBLOCK_MEMORY_REGIONS
33 #define INIT_MEMBLOCK_MEMORY_REGIONS		INIT_MEMBLOCK_REGIONS
34 #endif
35 
36 /**
37  * DOC: memblock overview
38  *
39  * Memblock is a method of managing memory regions during the early
40  * boot period when the usual kernel memory allocators are not up and
41  * running.
42  *
43  * Memblock views the system memory as collections of contiguous
44  * regions. There are several types of these collections:
45  *
46  * * ``memory`` - describes the physical memory available to the
47  *   kernel; this may differ from the actual physical memory installed
48  *   in the system, for instance when the memory is restricted with
49  *   ``mem=`` command line parameter
50  * * ``reserved`` - describes the regions that were allocated
51  * * ``physmem`` - describes the actual physical memory available during
52  *   boot regardless of the possible restrictions and memory hot(un)plug;
53  *   the ``physmem`` type is only available on some architectures.
54  *
55  * Each region is represented by struct memblock_region that
56  * defines the region extents, its attributes and NUMA node id on NUMA
57  * systems. Every memory type is described by the struct memblock_type
58  * which contains an array of memory regions along with
59  * the allocator metadata. The "memory" and "reserved" types are nicely
60  * wrapped with struct memblock. This structure is statically
61  * initialized at build time. The region arrays are initially sized to
62  * %INIT_MEMBLOCK_MEMORY_REGIONS for "memory" and
63  * %INIT_MEMBLOCK_RESERVED_REGIONS for "reserved". The region array
64  * for "physmem" is initially sized to %INIT_PHYSMEM_REGIONS.
65  * The memblock_allow_resize() enables automatic resizing of the region
66  * arrays during addition of new regions. This feature should be used
67  * with care so that memory allocated for the region array will not
68  * overlap with areas that should be reserved, for example initrd.
69  *
70  * The early architecture setup should tell memblock what the physical
71  * memory layout is by using memblock_add() or memblock_add_node()
72  * functions. The first function does not assign the region to a NUMA
73  * node and it is appropriate for UMA systems. Yet, it is possible to
74  * use it on NUMA systems as well and assign the region to a NUMA node
75  * later in the setup process using memblock_set_node(). The
76  * memblock_add_node() performs such an assignment directly.
77  *
78  * Once memblock is setup the memory can be allocated using one of the
79  * API variants:
80  *
81  * * memblock_phys_alloc*() - these functions return the **physical**
82  *   address of the allocated memory
83  * * memblock_alloc*() - these functions return the **virtual** address
84  *   of the allocated memory.
85  *
86  * Note, that both API variants use implicit assumptions about allowed
87  * memory ranges and the fallback methods. Consult the documentation
88  * of memblock_alloc_internal() and memblock_alloc_range_nid()
89  * functions for more elaborate description.
90  *
91  * As the system boot progresses, the architecture specific mem_init()
92  * function frees all the memory to the buddy page allocator.
93  *
94  * Unless an architecture enables %CONFIG_ARCH_KEEP_MEMBLOCK, the
95  * memblock data structures (except "physmem") will be discarded after the
96  * system initialization completes.
97  */
98 
99 #ifndef CONFIG_NUMA
100 struct pglist_data __refdata contig_page_data;
101 EXPORT_SYMBOL(contig_page_data);
102 #endif
103 
104 unsigned long max_low_pfn;
105 unsigned long min_low_pfn;
106 unsigned long max_pfn;
107 unsigned long long max_possible_pfn;
108 
109 static struct memblock_region memblock_memory_init_regions[INIT_MEMBLOCK_MEMORY_REGIONS] __initdata_memblock;
110 static struct memblock_region memblock_reserved_init_regions[INIT_MEMBLOCK_RESERVED_REGIONS] __initdata_memblock;
111 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
112 static struct memblock_region memblock_physmem_init_regions[INIT_PHYSMEM_REGIONS];
113 #endif
114 
115 struct memblock memblock __initdata_memblock = {
116 	.memory.regions		= memblock_memory_init_regions,
117 	.memory.cnt		= 1,	/* empty dummy entry */
118 	.memory.max		= INIT_MEMBLOCK_MEMORY_REGIONS,
119 	.memory.name		= "memory",
120 
121 	.reserved.regions	= memblock_reserved_init_regions,
122 	.reserved.cnt		= 1,	/* empty dummy entry */
123 	.reserved.max		= INIT_MEMBLOCK_RESERVED_REGIONS,
124 	.reserved.name		= "reserved",
125 
126 	.bottom_up		= false,
127 	.current_limit		= MEMBLOCK_ALLOC_ANYWHERE,
128 };
129 
130 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
131 struct memblock_type physmem = {
132 	.regions		= memblock_physmem_init_regions,
133 	.cnt			= 1,	/* empty dummy entry */
134 	.max			= INIT_PHYSMEM_REGIONS,
135 	.name			= "physmem",
136 };
137 #endif
138 
139 /*
140  * keep a pointer to &memblock.memory in the text section to use it in
141  * __next_mem_range() and its helpers.
142  *  For architectures that do not keep memblock data after init, this
143  * pointer will be reset to NULL at memblock_discard()
144  */
145 static __refdata struct memblock_type *memblock_memory = &memblock.memory;
146 
147 #define for_each_memblock_type(i, memblock_type, rgn)			\
148 	for (i = 0, rgn = &memblock_type->regions[0];			\
149 	     i < memblock_type->cnt;					\
150 	     i++, rgn = &memblock_type->regions[i])
151 
152 #define memblock_dbg(fmt, ...)						\
153 	do {								\
154 		if (memblock_debug)					\
155 			pr_info(fmt, ##__VA_ARGS__);			\
156 	} while (0)
157 
158 static int memblock_debug __initdata_memblock;
159 static bool system_has_some_mirror __initdata_memblock = false;
160 static int memblock_can_resize __initdata_memblock;
161 static int memblock_memory_in_slab __initdata_memblock = 0;
162 static int memblock_reserved_in_slab __initdata_memblock = 0;
163 
164 static enum memblock_flags __init_memblock choose_memblock_flags(void)
165 {
166 	return system_has_some_mirror ? MEMBLOCK_MIRROR : MEMBLOCK_NONE;
167 }
168 
169 /* adjust *@size so that (@base + *@size) doesn't overflow, return new size */
170 static inline phys_addr_t memblock_cap_size(phys_addr_t base, phys_addr_t *size)
171 {
172 	return *size = min(*size, PHYS_ADDR_MAX - base);
173 }
174 
175 /*
176  * Address comparison utilities
177  */
178 static unsigned long __init_memblock memblock_addrs_overlap(phys_addr_t base1, phys_addr_t size1,
179 				       phys_addr_t base2, phys_addr_t size2)
180 {
181 	return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
182 }
183 
184 bool __init_memblock memblock_overlaps_region(struct memblock_type *type,
185 					phys_addr_t base, phys_addr_t size)
186 {
187 	unsigned long i;
188 
189 	memblock_cap_size(base, &size);
190 
191 	for (i = 0; i < type->cnt; i++)
192 		if (memblock_addrs_overlap(base, size, type->regions[i].base,
193 					   type->regions[i].size))
194 			break;
195 	return i < type->cnt;
196 }
197 
198 /**
199  * __memblock_find_range_bottom_up - find free area utility in bottom-up
200  * @start: start of candidate range
201  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
202  *       %MEMBLOCK_ALLOC_ACCESSIBLE
203  * @size: size of free area to find
204  * @align: alignment of free area to find
205  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
206  * @flags: pick from blocks based on memory attributes
207  *
208  * Utility called from memblock_find_in_range_node(), find free area bottom-up.
209  *
210  * Return:
211  * Found address on success, 0 on failure.
212  */
213 static phys_addr_t __init_memblock
214 __memblock_find_range_bottom_up(phys_addr_t start, phys_addr_t end,
215 				phys_addr_t size, phys_addr_t align, int nid,
216 				enum memblock_flags flags)
217 {
218 	phys_addr_t this_start, this_end, cand;
219 	u64 i;
220 
221 	for_each_free_mem_range(i, nid, flags, &this_start, &this_end, NULL) {
222 		this_start = clamp(this_start, start, end);
223 		this_end = clamp(this_end, start, end);
224 
225 		cand = round_up(this_start, align);
226 		if (cand < this_end && this_end - cand >= size)
227 			return cand;
228 	}
229 
230 	return 0;
231 }
232 
233 /**
234  * __memblock_find_range_top_down - find free area utility, in top-down
235  * @start: start of candidate range
236  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
237  *       %MEMBLOCK_ALLOC_ACCESSIBLE
238  * @size: size of free area to find
239  * @align: alignment of free area to find
240  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
241  * @flags: pick from blocks based on memory attributes
242  *
243  * Utility called from memblock_find_in_range_node(), find free area top-down.
244  *
245  * Return:
246  * Found address on success, 0 on failure.
247  */
248 static phys_addr_t __init_memblock
249 __memblock_find_range_top_down(phys_addr_t start, phys_addr_t end,
250 			       phys_addr_t size, phys_addr_t align, int nid,
251 			       enum memblock_flags flags)
252 {
253 	phys_addr_t this_start, this_end, cand;
254 	u64 i;
255 
256 	for_each_free_mem_range_reverse(i, nid, flags, &this_start, &this_end,
257 					NULL) {
258 		this_start = clamp(this_start, start, end);
259 		this_end = clamp(this_end, start, end);
260 
261 		if (this_end < size)
262 			continue;
263 
264 		cand = round_down(this_end - size, align);
265 		if (cand >= this_start)
266 			return cand;
267 	}
268 
269 	return 0;
270 }
271 
272 /**
273  * memblock_find_in_range_node - find free area in given range and node
274  * @size: size of free area to find
275  * @align: alignment of free area to find
276  * @start: start of candidate range
277  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
278  *       %MEMBLOCK_ALLOC_ACCESSIBLE
279  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
280  * @flags: pick from blocks based on memory attributes
281  *
282  * Find @size free area aligned to @align in the specified range and node.
283  *
284  * Return:
285  * Found address on success, 0 on failure.
286  */
287 static phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t size,
288 					phys_addr_t align, phys_addr_t start,
289 					phys_addr_t end, int nid,
290 					enum memblock_flags flags)
291 {
292 	/* pump up @end */
293 	if (end == MEMBLOCK_ALLOC_ACCESSIBLE ||
294 	    end == MEMBLOCK_ALLOC_NOLEAKTRACE)
295 		end = memblock.current_limit;
296 
297 	/* avoid allocating the first page */
298 	start = max_t(phys_addr_t, start, PAGE_SIZE);
299 	end = max(start, end);
300 
301 	if (memblock_bottom_up())
302 		return __memblock_find_range_bottom_up(start, end, size, align,
303 						       nid, flags);
304 	else
305 		return __memblock_find_range_top_down(start, end, size, align,
306 						      nid, flags);
307 }
308 
309 /**
310  * memblock_find_in_range - find free area in given range
311  * @start: start of candidate range
312  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
313  *       %MEMBLOCK_ALLOC_ACCESSIBLE
314  * @size: size of free area to find
315  * @align: alignment of free area to find
316  *
317  * Find @size free area aligned to @align in the specified range.
318  *
319  * Return:
320  * Found address on success, 0 on failure.
321  */
322 static phys_addr_t __init_memblock memblock_find_in_range(phys_addr_t start,
323 					phys_addr_t end, phys_addr_t size,
324 					phys_addr_t align)
325 {
326 	phys_addr_t ret;
327 	enum memblock_flags flags = choose_memblock_flags();
328 
329 again:
330 	ret = memblock_find_in_range_node(size, align, start, end,
331 					    NUMA_NO_NODE, flags);
332 
333 	if (!ret && (flags & MEMBLOCK_MIRROR)) {
334 		pr_warn_ratelimited("Could not allocate %pap bytes of mirrored memory\n",
335 			&size);
336 		flags &= ~MEMBLOCK_MIRROR;
337 		goto again;
338 	}
339 
340 	return ret;
341 }
342 
343 static void __init_memblock memblock_remove_region(struct memblock_type *type, unsigned long r)
344 {
345 	type->total_size -= type->regions[r].size;
346 	memmove(&type->regions[r], &type->regions[r + 1],
347 		(type->cnt - (r + 1)) * sizeof(type->regions[r]));
348 	type->cnt--;
349 
350 	/* Special case for empty arrays */
351 	if (type->cnt == 0) {
352 		WARN_ON(type->total_size != 0);
353 		type->cnt = 1;
354 		type->regions[0].base = 0;
355 		type->regions[0].size = 0;
356 		type->regions[0].flags = 0;
357 		memblock_set_region_node(&type->regions[0], MAX_NUMNODES);
358 	}
359 }
360 
361 #ifndef CONFIG_ARCH_KEEP_MEMBLOCK
362 /**
363  * memblock_discard - discard memory and reserved arrays if they were allocated
364  */
365 void __init memblock_discard(void)
366 {
367 	phys_addr_t addr, size;
368 
369 	if (memblock.reserved.regions != memblock_reserved_init_regions) {
370 		addr = __pa(memblock.reserved.regions);
371 		size = PAGE_ALIGN(sizeof(struct memblock_region) *
372 				  memblock.reserved.max);
373 		if (memblock_reserved_in_slab)
374 			kfree(memblock.reserved.regions);
375 		else
376 			memblock_free_late(addr, size);
377 	}
378 
379 	if (memblock.memory.regions != memblock_memory_init_regions) {
380 		addr = __pa(memblock.memory.regions);
381 		size = PAGE_ALIGN(sizeof(struct memblock_region) *
382 				  memblock.memory.max);
383 		if (memblock_memory_in_slab)
384 			kfree(memblock.memory.regions);
385 		else
386 			memblock_free_late(addr, size);
387 	}
388 
389 	memblock_memory = NULL;
390 }
391 #endif
392 
393 /**
394  * memblock_double_array - double the size of the memblock regions array
395  * @type: memblock type of the regions array being doubled
396  * @new_area_start: starting address of memory range to avoid overlap with
397  * @new_area_size: size of memory range to avoid overlap with
398  *
399  * Double the size of the @type regions array. If memblock is being used to
400  * allocate memory for a new reserved regions array and there is a previously
401  * allocated memory range [@new_area_start, @new_area_start + @new_area_size]
402  * waiting to be reserved, ensure the memory used by the new array does
403  * not overlap.
404  *
405  * Return:
406  * 0 on success, -1 on failure.
407  */
408 static int __init_memblock memblock_double_array(struct memblock_type *type,
409 						phys_addr_t new_area_start,
410 						phys_addr_t new_area_size)
411 {
412 	struct memblock_region *new_array, *old_array;
413 	phys_addr_t old_alloc_size, new_alloc_size;
414 	phys_addr_t old_size, new_size, addr, new_end;
415 	int use_slab = slab_is_available();
416 	int *in_slab;
417 
418 	/* We don't allow resizing until we know about the reserved regions
419 	 * of memory that aren't suitable for allocation
420 	 */
421 	if (!memblock_can_resize)
422 		return -1;
423 
424 	/* Calculate new doubled size */
425 	old_size = type->max * sizeof(struct memblock_region);
426 	new_size = old_size << 1;
427 	/*
428 	 * We need to allocated new one align to PAGE_SIZE,
429 	 *   so we can free them completely later.
430 	 */
431 	old_alloc_size = PAGE_ALIGN(old_size);
432 	new_alloc_size = PAGE_ALIGN(new_size);
433 
434 	/* Retrieve the slab flag */
435 	if (type == &memblock.memory)
436 		in_slab = &memblock_memory_in_slab;
437 	else
438 		in_slab = &memblock_reserved_in_slab;
439 
440 	/* Try to find some space for it */
441 	if (use_slab) {
442 		new_array = kmalloc(new_size, GFP_KERNEL);
443 		addr = new_array ? __pa(new_array) : 0;
444 	} else {
445 		/* only exclude range when trying to double reserved.regions */
446 		if (type != &memblock.reserved)
447 			new_area_start = new_area_size = 0;
448 
449 		addr = memblock_find_in_range(new_area_start + new_area_size,
450 						memblock.current_limit,
451 						new_alloc_size, PAGE_SIZE);
452 		if (!addr && new_area_size)
453 			addr = memblock_find_in_range(0,
454 				min(new_area_start, memblock.current_limit),
455 				new_alloc_size, PAGE_SIZE);
456 
457 		new_array = addr ? __va(addr) : NULL;
458 	}
459 	if (!addr) {
460 		pr_err("memblock: Failed to double %s array from %ld to %ld entries !\n",
461 		       type->name, type->max, type->max * 2);
462 		return -1;
463 	}
464 
465 	new_end = addr + new_size - 1;
466 	memblock_dbg("memblock: %s is doubled to %ld at [%pa-%pa]",
467 			type->name, type->max * 2, &addr, &new_end);
468 
469 	/*
470 	 * Found space, we now need to move the array over before we add the
471 	 * reserved region since it may be our reserved array itself that is
472 	 * full.
473 	 */
474 	memcpy(new_array, type->regions, old_size);
475 	memset(new_array + type->max, 0, old_size);
476 	old_array = type->regions;
477 	type->regions = new_array;
478 	type->max <<= 1;
479 
480 	/* Free old array. We needn't free it if the array is the static one */
481 	if (*in_slab)
482 		kfree(old_array);
483 	else if (old_array != memblock_memory_init_regions &&
484 		 old_array != memblock_reserved_init_regions)
485 		memblock_free(old_array, old_alloc_size);
486 
487 	/*
488 	 * Reserve the new array if that comes from the memblock.  Otherwise, we
489 	 * needn't do it
490 	 */
491 	if (!use_slab)
492 		BUG_ON(memblock_reserve(addr, new_alloc_size));
493 
494 	/* Update slab flag */
495 	*in_slab = use_slab;
496 
497 	return 0;
498 }
499 
500 /**
501  * memblock_merge_regions - merge neighboring compatible regions
502  * @type: memblock type to scan
503  *
504  * Scan @type and merge neighboring compatible regions.
505  */
506 static void __init_memblock memblock_merge_regions(struct memblock_type *type)
507 {
508 	int i = 0;
509 
510 	/* cnt never goes below 1 */
511 	while (i < type->cnt - 1) {
512 		struct memblock_region *this = &type->regions[i];
513 		struct memblock_region *next = &type->regions[i + 1];
514 
515 		if (this->base + this->size != next->base ||
516 		    memblock_get_region_node(this) !=
517 		    memblock_get_region_node(next) ||
518 		    this->flags != next->flags) {
519 			BUG_ON(this->base + this->size > next->base);
520 			i++;
521 			continue;
522 		}
523 
524 		this->size += next->size;
525 		/* move forward from next + 1, index of which is i + 2 */
526 		memmove(next, next + 1, (type->cnt - (i + 2)) * sizeof(*next));
527 		type->cnt--;
528 	}
529 }
530 
531 /**
532  * memblock_insert_region - insert new memblock region
533  * @type:	memblock type to insert into
534  * @idx:	index for the insertion point
535  * @base:	base address of the new region
536  * @size:	size of the new region
537  * @nid:	node id of the new region
538  * @flags:	flags of the new region
539  *
540  * Insert new memblock region [@base, @base + @size) into @type at @idx.
541  * @type must already have extra room to accommodate the new region.
542  */
543 static void __init_memblock memblock_insert_region(struct memblock_type *type,
544 						   int idx, phys_addr_t base,
545 						   phys_addr_t size,
546 						   int nid,
547 						   enum memblock_flags flags)
548 {
549 	struct memblock_region *rgn = &type->regions[idx];
550 
551 	BUG_ON(type->cnt >= type->max);
552 	memmove(rgn + 1, rgn, (type->cnt - idx) * sizeof(*rgn));
553 	rgn->base = base;
554 	rgn->size = size;
555 	rgn->flags = flags;
556 	memblock_set_region_node(rgn, nid);
557 	type->cnt++;
558 	type->total_size += size;
559 }
560 
561 /**
562  * memblock_add_range - add new memblock region
563  * @type: memblock type to add new region into
564  * @base: base address of the new region
565  * @size: size of the new region
566  * @nid: nid of the new region
567  * @flags: flags of the new region
568  *
569  * Add new memblock region [@base, @base + @size) into @type.  The new region
570  * is allowed to overlap with existing ones - overlaps don't affect already
571  * existing regions.  @type is guaranteed to be minimal (all neighbouring
572  * compatible regions are merged) after the addition.
573  *
574  * Return:
575  * 0 on success, -errno on failure.
576  */
577 static int __init_memblock memblock_add_range(struct memblock_type *type,
578 				phys_addr_t base, phys_addr_t size,
579 				int nid, enum memblock_flags flags)
580 {
581 	bool insert = false;
582 	phys_addr_t obase = base;
583 	phys_addr_t end = base + memblock_cap_size(base, &size);
584 	int idx, nr_new;
585 	struct memblock_region *rgn;
586 
587 	if (!size)
588 		return 0;
589 
590 	/* special case for empty array */
591 	if (type->regions[0].size == 0) {
592 		WARN_ON(type->cnt != 1 || type->total_size);
593 		type->regions[0].base = base;
594 		type->regions[0].size = size;
595 		type->regions[0].flags = flags;
596 		memblock_set_region_node(&type->regions[0], nid);
597 		type->total_size = size;
598 		return 0;
599 	}
600 repeat:
601 	/*
602 	 * The following is executed twice.  Once with %false @insert and
603 	 * then with %true.  The first counts the number of regions needed
604 	 * to accommodate the new area.  The second actually inserts them.
605 	 */
606 	base = obase;
607 	nr_new = 0;
608 
609 	for_each_memblock_type(idx, type, rgn) {
610 		phys_addr_t rbase = rgn->base;
611 		phys_addr_t rend = rbase + rgn->size;
612 
613 		if (rbase >= end)
614 			break;
615 		if (rend <= base)
616 			continue;
617 		/*
618 		 * @rgn overlaps.  If it separates the lower part of new
619 		 * area, insert that portion.
620 		 */
621 		if (rbase > base) {
622 #ifdef CONFIG_NUMA
623 			WARN_ON(nid != memblock_get_region_node(rgn));
624 #endif
625 			WARN_ON(flags != rgn->flags);
626 			nr_new++;
627 			if (insert)
628 				memblock_insert_region(type, idx++, base,
629 						       rbase - base, nid,
630 						       flags);
631 		}
632 		/* area below @rend is dealt with, forget about it */
633 		base = min(rend, end);
634 	}
635 
636 	/* insert the remaining portion */
637 	if (base < end) {
638 		nr_new++;
639 		if (insert)
640 			memblock_insert_region(type, idx, base, end - base,
641 					       nid, flags);
642 	}
643 
644 	if (!nr_new)
645 		return 0;
646 
647 	/*
648 	 * If this was the first round, resize array and repeat for actual
649 	 * insertions; otherwise, merge and return.
650 	 */
651 	if (!insert) {
652 		while (type->cnt + nr_new > type->max)
653 			if (memblock_double_array(type, obase, size) < 0)
654 				return -ENOMEM;
655 		insert = true;
656 		goto repeat;
657 	} else {
658 		memblock_merge_regions(type);
659 		return 0;
660 	}
661 }
662 
663 /**
664  * memblock_add_node - add new memblock region within a NUMA node
665  * @base: base address of the new region
666  * @size: size of the new region
667  * @nid: nid of the new region
668  * @flags: flags of the new region
669  *
670  * Add new memblock region [@base, @base + @size) to the "memory"
671  * type. See memblock_add_range() description for mode details
672  *
673  * Return:
674  * 0 on success, -errno on failure.
675  */
676 int __init_memblock memblock_add_node(phys_addr_t base, phys_addr_t size,
677 				      int nid, enum memblock_flags flags)
678 {
679 	phys_addr_t end = base + size - 1;
680 
681 	memblock_dbg("%s: [%pa-%pa] nid=%d flags=%x %pS\n", __func__,
682 		     &base, &end, nid, flags, (void *)_RET_IP_);
683 
684 	return memblock_add_range(&memblock.memory, base, size, nid, flags);
685 }
686 
687 /**
688  * memblock_add - add new memblock region
689  * @base: base address of the new region
690  * @size: size of the new region
691  *
692  * Add new memblock region [@base, @base + @size) to the "memory"
693  * type. See memblock_add_range() description for mode details
694  *
695  * Return:
696  * 0 on success, -errno on failure.
697  */
698 int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
699 {
700 	phys_addr_t end = base + size - 1;
701 
702 	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
703 		     &base, &end, (void *)_RET_IP_);
704 
705 	return memblock_add_range(&memblock.memory, base, size, MAX_NUMNODES, 0);
706 }
707 
708 /**
709  * memblock_isolate_range - isolate given range into disjoint memblocks
710  * @type: memblock type to isolate range for
711  * @base: base of range to isolate
712  * @size: size of range to isolate
713  * @start_rgn: out parameter for the start of isolated region
714  * @end_rgn: out parameter for the end of isolated region
715  *
716  * Walk @type and ensure that regions don't cross the boundaries defined by
717  * [@base, @base + @size).  Crossing regions are split at the boundaries,
718  * which may create at most two more regions.  The index of the first
719  * region inside the range is returned in *@start_rgn and end in *@end_rgn.
720  *
721  * Return:
722  * 0 on success, -errno on failure.
723  */
724 static int __init_memblock memblock_isolate_range(struct memblock_type *type,
725 					phys_addr_t base, phys_addr_t size,
726 					int *start_rgn, int *end_rgn)
727 {
728 	phys_addr_t end = base + memblock_cap_size(base, &size);
729 	int idx;
730 	struct memblock_region *rgn;
731 
732 	*start_rgn = *end_rgn = 0;
733 
734 	if (!size)
735 		return 0;
736 
737 	/* we'll create at most two more regions */
738 	while (type->cnt + 2 > type->max)
739 		if (memblock_double_array(type, base, size) < 0)
740 			return -ENOMEM;
741 
742 	for_each_memblock_type(idx, type, rgn) {
743 		phys_addr_t rbase = rgn->base;
744 		phys_addr_t rend = rbase + rgn->size;
745 
746 		if (rbase >= end)
747 			break;
748 		if (rend <= base)
749 			continue;
750 
751 		if (rbase < base) {
752 			/*
753 			 * @rgn intersects from below.  Split and continue
754 			 * to process the next region - the new top half.
755 			 */
756 			rgn->base = base;
757 			rgn->size -= base - rbase;
758 			type->total_size -= base - rbase;
759 			memblock_insert_region(type, idx, rbase, base - rbase,
760 					       memblock_get_region_node(rgn),
761 					       rgn->flags);
762 		} else if (rend > end) {
763 			/*
764 			 * @rgn intersects from above.  Split and redo the
765 			 * current region - the new bottom half.
766 			 */
767 			rgn->base = end;
768 			rgn->size -= end - rbase;
769 			type->total_size -= end - rbase;
770 			memblock_insert_region(type, idx--, rbase, end - rbase,
771 					       memblock_get_region_node(rgn),
772 					       rgn->flags);
773 		} else {
774 			/* @rgn is fully contained, record it */
775 			if (!*end_rgn)
776 				*start_rgn = idx;
777 			*end_rgn = idx + 1;
778 		}
779 	}
780 
781 	return 0;
782 }
783 
784 static int __init_memblock memblock_remove_range(struct memblock_type *type,
785 					  phys_addr_t base, phys_addr_t size)
786 {
787 	int start_rgn, end_rgn;
788 	int i, ret;
789 
790 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
791 	if (ret)
792 		return ret;
793 
794 	for (i = end_rgn - 1; i >= start_rgn; i--)
795 		memblock_remove_region(type, i);
796 	return 0;
797 }
798 
799 int __init_memblock memblock_remove(phys_addr_t base, phys_addr_t size)
800 {
801 	phys_addr_t end = base + size - 1;
802 
803 	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
804 		     &base, &end, (void *)_RET_IP_);
805 
806 	return memblock_remove_range(&memblock.memory, base, size);
807 }
808 
809 /**
810  * memblock_free - free boot memory allocation
811  * @ptr: starting address of the  boot memory allocation
812  * @size: size of the boot memory block in bytes
813  *
814  * Free boot memory block previously allocated by memblock_alloc_xx() API.
815  * The freeing memory will not be released to the buddy allocator.
816  */
817 void __init_memblock memblock_free(void *ptr, size_t size)
818 {
819 	if (ptr)
820 		memblock_phys_free(__pa(ptr), size);
821 }
822 
823 /**
824  * memblock_phys_free - free boot memory block
825  * @base: phys starting address of the  boot memory block
826  * @size: size of the boot memory block in bytes
827  *
828  * Free boot memory block previously allocated by memblock_alloc_xx() API.
829  * The freeing memory will not be released to the buddy allocator.
830  */
831 int __init_memblock memblock_phys_free(phys_addr_t base, phys_addr_t size)
832 {
833 	phys_addr_t end = base + size - 1;
834 
835 	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
836 		     &base, &end, (void *)_RET_IP_);
837 
838 	kmemleak_free_part_phys(base, size);
839 	return memblock_remove_range(&memblock.reserved, base, size);
840 }
841 
842 int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
843 {
844 	phys_addr_t end = base + size - 1;
845 
846 	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
847 		     &base, &end, (void *)_RET_IP_);
848 
849 	return memblock_add_range(&memblock.reserved, base, size, MAX_NUMNODES, 0);
850 }
851 
852 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
853 int __init_memblock memblock_physmem_add(phys_addr_t base, phys_addr_t size)
854 {
855 	phys_addr_t end = base + size - 1;
856 
857 	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
858 		     &base, &end, (void *)_RET_IP_);
859 
860 	return memblock_add_range(&physmem, base, size, MAX_NUMNODES, 0);
861 }
862 #endif
863 
864 /**
865  * memblock_setclr_flag - set or clear flag for a memory region
866  * @base: base address of the region
867  * @size: size of the region
868  * @set: set or clear the flag
869  * @flag: the flag to update
870  *
871  * This function isolates region [@base, @base + @size), and sets/clears flag
872  *
873  * Return: 0 on success, -errno on failure.
874  */
875 static int __init_memblock memblock_setclr_flag(phys_addr_t base,
876 				phys_addr_t size, int set, int flag)
877 {
878 	struct memblock_type *type = &memblock.memory;
879 	int i, ret, start_rgn, end_rgn;
880 
881 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
882 	if (ret)
883 		return ret;
884 
885 	for (i = start_rgn; i < end_rgn; i++) {
886 		struct memblock_region *r = &type->regions[i];
887 
888 		if (set)
889 			r->flags |= flag;
890 		else
891 			r->flags &= ~flag;
892 	}
893 
894 	memblock_merge_regions(type);
895 	return 0;
896 }
897 
898 /**
899  * memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
900  * @base: the base phys addr of the region
901  * @size: the size of the region
902  *
903  * Return: 0 on success, -errno on failure.
904  */
905 int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
906 {
907 	return memblock_setclr_flag(base, size, 1, MEMBLOCK_HOTPLUG);
908 }
909 
910 /**
911  * memblock_clear_hotplug - Clear flag MEMBLOCK_HOTPLUG for a specified region.
912  * @base: the base phys addr of the region
913  * @size: the size of the region
914  *
915  * Return: 0 on success, -errno on failure.
916  */
917 int __init_memblock memblock_clear_hotplug(phys_addr_t base, phys_addr_t size)
918 {
919 	return memblock_setclr_flag(base, size, 0, MEMBLOCK_HOTPLUG);
920 }
921 
922 /**
923  * memblock_mark_mirror - Mark mirrored memory with flag MEMBLOCK_MIRROR.
924  * @base: the base phys addr of the region
925  * @size: the size of the region
926  *
927  * Return: 0 on success, -errno on failure.
928  */
929 int __init_memblock memblock_mark_mirror(phys_addr_t base, phys_addr_t size)
930 {
931 	if (!mirrored_kernelcore)
932 		return 0;
933 
934 	system_has_some_mirror = true;
935 
936 	return memblock_setclr_flag(base, size, 1, MEMBLOCK_MIRROR);
937 }
938 
939 /**
940  * memblock_mark_nomap - Mark a memory region with flag MEMBLOCK_NOMAP.
941  * @base: the base phys addr of the region
942  * @size: the size of the region
943  *
944  * The memory regions marked with %MEMBLOCK_NOMAP will not be added to the
945  * direct mapping of the physical memory. These regions will still be
946  * covered by the memory map. The struct page representing NOMAP memory
947  * frames in the memory map will be PageReserved()
948  *
949  * Note: if the memory being marked %MEMBLOCK_NOMAP was allocated from
950  * memblock, the caller must inform kmemleak to ignore that memory
951  *
952  * Return: 0 on success, -errno on failure.
953  */
954 int __init_memblock memblock_mark_nomap(phys_addr_t base, phys_addr_t size)
955 {
956 	return memblock_setclr_flag(base, size, 1, MEMBLOCK_NOMAP);
957 }
958 
959 /**
960  * memblock_clear_nomap - Clear flag MEMBLOCK_NOMAP for a specified region.
961  * @base: the base phys addr of the region
962  * @size: the size of the region
963  *
964  * Return: 0 on success, -errno on failure.
965  */
966 int __init_memblock memblock_clear_nomap(phys_addr_t base, phys_addr_t size)
967 {
968 	return memblock_setclr_flag(base, size, 0, MEMBLOCK_NOMAP);
969 }
970 
971 static bool should_skip_region(struct memblock_type *type,
972 			       struct memblock_region *m,
973 			       int nid, int flags)
974 {
975 	int m_nid = memblock_get_region_node(m);
976 
977 	/* we never skip regions when iterating memblock.reserved or physmem */
978 	if (type != memblock_memory)
979 		return false;
980 
981 	/* only memory regions are associated with nodes, check it */
982 	if (nid != NUMA_NO_NODE && nid != m_nid)
983 		return true;
984 
985 	/* skip hotpluggable memory regions if needed */
986 	if (movable_node_is_enabled() && memblock_is_hotpluggable(m) &&
987 	    !(flags & MEMBLOCK_HOTPLUG))
988 		return true;
989 
990 	/* if we want mirror memory skip non-mirror memory regions */
991 	if ((flags & MEMBLOCK_MIRROR) && !memblock_is_mirror(m))
992 		return true;
993 
994 	/* skip nomap memory unless we were asked for it explicitly */
995 	if (!(flags & MEMBLOCK_NOMAP) && memblock_is_nomap(m))
996 		return true;
997 
998 	/* skip driver-managed memory unless we were asked for it explicitly */
999 	if (!(flags & MEMBLOCK_DRIVER_MANAGED) && memblock_is_driver_managed(m))
1000 		return true;
1001 
1002 	return false;
1003 }
1004 
1005 /**
1006  * __next_mem_range - next function for for_each_free_mem_range() etc.
1007  * @idx: pointer to u64 loop variable
1008  * @nid: node selector, %NUMA_NO_NODE for all nodes
1009  * @flags: pick from blocks based on memory attributes
1010  * @type_a: pointer to memblock_type from where the range is taken
1011  * @type_b: pointer to memblock_type which excludes memory from being taken
1012  * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
1013  * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
1014  * @out_nid: ptr to int for nid of the range, can be %NULL
1015  *
1016  * Find the first area from *@idx which matches @nid, fill the out
1017  * parameters, and update *@idx for the next iteration.  The lower 32bit of
1018  * *@idx contains index into type_a and the upper 32bit indexes the
1019  * areas before each region in type_b.	For example, if type_b regions
1020  * look like the following,
1021  *
1022  *	0:[0-16), 1:[32-48), 2:[128-130)
1023  *
1024  * The upper 32bit indexes the following regions.
1025  *
1026  *	0:[0-0), 1:[16-32), 2:[48-128), 3:[130-MAX)
1027  *
1028  * As both region arrays are sorted, the function advances the two indices
1029  * in lockstep and returns each intersection.
1030  */
1031 void __next_mem_range(u64 *idx, int nid, enum memblock_flags flags,
1032 		      struct memblock_type *type_a,
1033 		      struct memblock_type *type_b, phys_addr_t *out_start,
1034 		      phys_addr_t *out_end, int *out_nid)
1035 {
1036 	int idx_a = *idx & 0xffffffff;
1037 	int idx_b = *idx >> 32;
1038 
1039 	if (WARN_ONCE(nid == MAX_NUMNODES,
1040 	"Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
1041 		nid = NUMA_NO_NODE;
1042 
1043 	for (; idx_a < type_a->cnt; idx_a++) {
1044 		struct memblock_region *m = &type_a->regions[idx_a];
1045 
1046 		phys_addr_t m_start = m->base;
1047 		phys_addr_t m_end = m->base + m->size;
1048 		int	    m_nid = memblock_get_region_node(m);
1049 
1050 		if (should_skip_region(type_a, m, nid, flags))
1051 			continue;
1052 
1053 		if (!type_b) {
1054 			if (out_start)
1055 				*out_start = m_start;
1056 			if (out_end)
1057 				*out_end = m_end;
1058 			if (out_nid)
1059 				*out_nid = m_nid;
1060 			idx_a++;
1061 			*idx = (u32)idx_a | (u64)idx_b << 32;
1062 			return;
1063 		}
1064 
1065 		/* scan areas before each reservation */
1066 		for (; idx_b < type_b->cnt + 1; idx_b++) {
1067 			struct memblock_region *r;
1068 			phys_addr_t r_start;
1069 			phys_addr_t r_end;
1070 
1071 			r = &type_b->regions[idx_b];
1072 			r_start = idx_b ? r[-1].base + r[-1].size : 0;
1073 			r_end = idx_b < type_b->cnt ?
1074 				r->base : PHYS_ADDR_MAX;
1075 
1076 			/*
1077 			 * if idx_b advanced past idx_a,
1078 			 * break out to advance idx_a
1079 			 */
1080 			if (r_start >= m_end)
1081 				break;
1082 			/* if the two regions intersect, we're done */
1083 			if (m_start < r_end) {
1084 				if (out_start)
1085 					*out_start =
1086 						max(m_start, r_start);
1087 				if (out_end)
1088 					*out_end = min(m_end, r_end);
1089 				if (out_nid)
1090 					*out_nid = m_nid;
1091 				/*
1092 				 * The region which ends first is
1093 				 * advanced for the next iteration.
1094 				 */
1095 				if (m_end <= r_end)
1096 					idx_a++;
1097 				else
1098 					idx_b++;
1099 				*idx = (u32)idx_a | (u64)idx_b << 32;
1100 				return;
1101 			}
1102 		}
1103 	}
1104 
1105 	/* signal end of iteration */
1106 	*idx = ULLONG_MAX;
1107 }
1108 
1109 /**
1110  * __next_mem_range_rev - generic next function for for_each_*_range_rev()
1111  *
1112  * @idx: pointer to u64 loop variable
1113  * @nid: node selector, %NUMA_NO_NODE for all nodes
1114  * @flags: pick from blocks based on memory attributes
1115  * @type_a: pointer to memblock_type from where the range is taken
1116  * @type_b: pointer to memblock_type which excludes memory from being taken
1117  * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
1118  * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
1119  * @out_nid: ptr to int for nid of the range, can be %NULL
1120  *
1121  * Finds the next range from type_a which is not marked as unsuitable
1122  * in type_b.
1123  *
1124  * Reverse of __next_mem_range().
1125  */
1126 void __init_memblock __next_mem_range_rev(u64 *idx, int nid,
1127 					  enum memblock_flags flags,
1128 					  struct memblock_type *type_a,
1129 					  struct memblock_type *type_b,
1130 					  phys_addr_t *out_start,
1131 					  phys_addr_t *out_end, int *out_nid)
1132 {
1133 	int idx_a = *idx & 0xffffffff;
1134 	int idx_b = *idx >> 32;
1135 
1136 	if (WARN_ONCE(nid == MAX_NUMNODES, "Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
1137 		nid = NUMA_NO_NODE;
1138 
1139 	if (*idx == (u64)ULLONG_MAX) {
1140 		idx_a = type_a->cnt - 1;
1141 		if (type_b != NULL)
1142 			idx_b = type_b->cnt;
1143 		else
1144 			idx_b = 0;
1145 	}
1146 
1147 	for (; idx_a >= 0; idx_a--) {
1148 		struct memblock_region *m = &type_a->regions[idx_a];
1149 
1150 		phys_addr_t m_start = m->base;
1151 		phys_addr_t m_end = m->base + m->size;
1152 		int m_nid = memblock_get_region_node(m);
1153 
1154 		if (should_skip_region(type_a, m, nid, flags))
1155 			continue;
1156 
1157 		if (!type_b) {
1158 			if (out_start)
1159 				*out_start = m_start;
1160 			if (out_end)
1161 				*out_end = m_end;
1162 			if (out_nid)
1163 				*out_nid = m_nid;
1164 			idx_a--;
1165 			*idx = (u32)idx_a | (u64)idx_b << 32;
1166 			return;
1167 		}
1168 
1169 		/* scan areas before each reservation */
1170 		for (; idx_b >= 0; idx_b--) {
1171 			struct memblock_region *r;
1172 			phys_addr_t r_start;
1173 			phys_addr_t r_end;
1174 
1175 			r = &type_b->regions[idx_b];
1176 			r_start = idx_b ? r[-1].base + r[-1].size : 0;
1177 			r_end = idx_b < type_b->cnt ?
1178 				r->base : PHYS_ADDR_MAX;
1179 			/*
1180 			 * if idx_b advanced past idx_a,
1181 			 * break out to advance idx_a
1182 			 */
1183 
1184 			if (r_end <= m_start)
1185 				break;
1186 			/* if the two regions intersect, we're done */
1187 			if (m_end > r_start) {
1188 				if (out_start)
1189 					*out_start = max(m_start, r_start);
1190 				if (out_end)
1191 					*out_end = min(m_end, r_end);
1192 				if (out_nid)
1193 					*out_nid = m_nid;
1194 				if (m_start >= r_start)
1195 					idx_a--;
1196 				else
1197 					idx_b--;
1198 				*idx = (u32)idx_a | (u64)idx_b << 32;
1199 				return;
1200 			}
1201 		}
1202 	}
1203 	/* signal end of iteration */
1204 	*idx = ULLONG_MAX;
1205 }
1206 
1207 /*
1208  * Common iterator interface used to define for_each_mem_pfn_range().
1209  */
1210 void __init_memblock __next_mem_pfn_range(int *idx, int nid,
1211 				unsigned long *out_start_pfn,
1212 				unsigned long *out_end_pfn, int *out_nid)
1213 {
1214 	struct memblock_type *type = &memblock.memory;
1215 	struct memblock_region *r;
1216 	int r_nid;
1217 
1218 	while (++*idx < type->cnt) {
1219 		r = &type->regions[*idx];
1220 		r_nid = memblock_get_region_node(r);
1221 
1222 		if (PFN_UP(r->base) >= PFN_DOWN(r->base + r->size))
1223 			continue;
1224 		if (nid == MAX_NUMNODES || nid == r_nid)
1225 			break;
1226 	}
1227 	if (*idx >= type->cnt) {
1228 		*idx = -1;
1229 		return;
1230 	}
1231 
1232 	if (out_start_pfn)
1233 		*out_start_pfn = PFN_UP(r->base);
1234 	if (out_end_pfn)
1235 		*out_end_pfn = PFN_DOWN(r->base + r->size);
1236 	if (out_nid)
1237 		*out_nid = r_nid;
1238 }
1239 
1240 /**
1241  * memblock_set_node - set node ID on memblock regions
1242  * @base: base of area to set node ID for
1243  * @size: size of area to set node ID for
1244  * @type: memblock type to set node ID for
1245  * @nid: node ID to set
1246  *
1247  * Set the nid of memblock @type regions in [@base, @base + @size) to @nid.
1248  * Regions which cross the area boundaries are split as necessary.
1249  *
1250  * Return:
1251  * 0 on success, -errno on failure.
1252  */
1253 int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
1254 				      struct memblock_type *type, int nid)
1255 {
1256 #ifdef CONFIG_NUMA
1257 	int start_rgn, end_rgn;
1258 	int i, ret;
1259 
1260 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
1261 	if (ret)
1262 		return ret;
1263 
1264 	for (i = start_rgn; i < end_rgn; i++)
1265 		memblock_set_region_node(&type->regions[i], nid);
1266 
1267 	memblock_merge_regions(type);
1268 #endif
1269 	return 0;
1270 }
1271 
1272 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
1273 /**
1274  * __next_mem_pfn_range_in_zone - iterator for for_each_*_range_in_zone()
1275  *
1276  * @idx: pointer to u64 loop variable
1277  * @zone: zone in which all of the memory blocks reside
1278  * @out_spfn: ptr to ulong for start pfn of the range, can be %NULL
1279  * @out_epfn: ptr to ulong for end pfn of the range, can be %NULL
1280  *
1281  * This function is meant to be a zone/pfn specific wrapper for the
1282  * for_each_mem_range type iterators. Specifically they are used in the
1283  * deferred memory init routines and as such we were duplicating much of
1284  * this logic throughout the code. So instead of having it in multiple
1285  * locations it seemed like it would make more sense to centralize this to
1286  * one new iterator that does everything they need.
1287  */
1288 void __init_memblock
1289 __next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone,
1290 			     unsigned long *out_spfn, unsigned long *out_epfn)
1291 {
1292 	int zone_nid = zone_to_nid(zone);
1293 	phys_addr_t spa, epa;
1294 
1295 	__next_mem_range(idx, zone_nid, MEMBLOCK_NONE,
1296 			 &memblock.memory, &memblock.reserved,
1297 			 &spa, &epa, NULL);
1298 
1299 	while (*idx != U64_MAX) {
1300 		unsigned long epfn = PFN_DOWN(epa);
1301 		unsigned long spfn = PFN_UP(spa);
1302 
1303 		/*
1304 		 * Verify the end is at least past the start of the zone and
1305 		 * that we have at least one PFN to initialize.
1306 		 */
1307 		if (zone->zone_start_pfn < epfn && spfn < epfn) {
1308 			/* if we went too far just stop searching */
1309 			if (zone_end_pfn(zone) <= spfn) {
1310 				*idx = U64_MAX;
1311 				break;
1312 			}
1313 
1314 			if (out_spfn)
1315 				*out_spfn = max(zone->zone_start_pfn, spfn);
1316 			if (out_epfn)
1317 				*out_epfn = min(zone_end_pfn(zone), epfn);
1318 
1319 			return;
1320 		}
1321 
1322 		__next_mem_range(idx, zone_nid, MEMBLOCK_NONE,
1323 				 &memblock.memory, &memblock.reserved,
1324 				 &spa, &epa, NULL);
1325 	}
1326 
1327 	/* signal end of iteration */
1328 	if (out_spfn)
1329 		*out_spfn = ULONG_MAX;
1330 	if (out_epfn)
1331 		*out_epfn = 0;
1332 }
1333 
1334 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
1335 
1336 /**
1337  * memblock_alloc_range_nid - allocate boot memory block
1338  * @size: size of memory block to be allocated in bytes
1339  * @align: alignment of the region and block's size
1340  * @start: the lower bound of the memory region to allocate (phys address)
1341  * @end: the upper bound of the memory region to allocate (phys address)
1342  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1343  * @exact_nid: control the allocation fall back to other nodes
1344  *
1345  * The allocation is performed from memory region limited by
1346  * memblock.current_limit if @end == %MEMBLOCK_ALLOC_ACCESSIBLE.
1347  *
1348  * If the specified node can not hold the requested memory and @exact_nid
1349  * is false, the allocation falls back to any node in the system.
1350  *
1351  * For systems with memory mirroring, the allocation is attempted first
1352  * from the regions with mirroring enabled and then retried from any
1353  * memory region.
1354  *
1355  * In addition, function using kmemleak_alloc_phys for allocated boot
1356  * memory block, it is never reported as leaks.
1357  *
1358  * Return:
1359  * Physical address of allocated memory block on success, %0 on failure.
1360  */
1361 phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size,
1362 					phys_addr_t align, phys_addr_t start,
1363 					phys_addr_t end, int nid,
1364 					bool exact_nid)
1365 {
1366 	enum memblock_flags flags = choose_memblock_flags();
1367 	phys_addr_t found;
1368 
1369 	if (WARN_ONCE(nid == MAX_NUMNODES, "Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
1370 		nid = NUMA_NO_NODE;
1371 
1372 	if (!align) {
1373 		/* Can't use WARNs this early in boot on powerpc */
1374 		dump_stack();
1375 		align = SMP_CACHE_BYTES;
1376 	}
1377 
1378 again:
1379 	found = memblock_find_in_range_node(size, align, start, end, nid,
1380 					    flags);
1381 	if (found && !memblock_reserve(found, size))
1382 		goto done;
1383 
1384 	if (nid != NUMA_NO_NODE && !exact_nid) {
1385 		found = memblock_find_in_range_node(size, align, start,
1386 						    end, NUMA_NO_NODE,
1387 						    flags);
1388 		if (found && !memblock_reserve(found, size))
1389 			goto done;
1390 	}
1391 
1392 	if (flags & MEMBLOCK_MIRROR) {
1393 		flags &= ~MEMBLOCK_MIRROR;
1394 		pr_warn_ratelimited("Could not allocate %pap bytes of mirrored memory\n",
1395 			&size);
1396 		goto again;
1397 	}
1398 
1399 	return 0;
1400 
1401 done:
1402 	/*
1403 	 * Skip kmemleak for those places like kasan_init() and
1404 	 * early_pgtable_alloc() due to high volume.
1405 	 */
1406 	if (end != MEMBLOCK_ALLOC_NOLEAKTRACE)
1407 		/*
1408 		 * Memblock allocated blocks are never reported as
1409 		 * leaks. This is because many of these blocks are
1410 		 * only referred via the physical address which is
1411 		 * not looked up by kmemleak.
1412 		 */
1413 		kmemleak_alloc_phys(found, size, 0);
1414 
1415 	return found;
1416 }
1417 
1418 /**
1419  * memblock_phys_alloc_range - allocate a memory block inside specified range
1420  * @size: size of memory block to be allocated in bytes
1421  * @align: alignment of the region and block's size
1422  * @start: the lower bound of the memory region to allocate (physical address)
1423  * @end: the upper bound of the memory region to allocate (physical address)
1424  *
1425  * Allocate @size bytes in the between @start and @end.
1426  *
1427  * Return: physical address of the allocated memory block on success,
1428  * %0 on failure.
1429  */
1430 phys_addr_t __init memblock_phys_alloc_range(phys_addr_t size,
1431 					     phys_addr_t align,
1432 					     phys_addr_t start,
1433 					     phys_addr_t end)
1434 {
1435 	memblock_dbg("%s: %llu bytes align=0x%llx from=%pa max_addr=%pa %pS\n",
1436 		     __func__, (u64)size, (u64)align, &start, &end,
1437 		     (void *)_RET_IP_);
1438 	return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE,
1439 					false);
1440 }
1441 
1442 /**
1443  * memblock_phys_alloc_try_nid - allocate a memory block from specified NUMA node
1444  * @size: size of memory block to be allocated in bytes
1445  * @align: alignment of the region and block's size
1446  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1447  *
1448  * Allocates memory block from the specified NUMA node. If the node
1449  * has no available memory, attempts to allocated from any node in the
1450  * system.
1451  *
1452  * Return: physical address of the allocated memory block on success,
1453  * %0 on failure.
1454  */
1455 phys_addr_t __init memblock_phys_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
1456 {
1457 	return memblock_alloc_range_nid(size, align, 0,
1458 					MEMBLOCK_ALLOC_ACCESSIBLE, nid, false);
1459 }
1460 
1461 /**
1462  * memblock_alloc_internal - allocate boot memory block
1463  * @size: size of memory block to be allocated in bytes
1464  * @align: alignment of the region and block's size
1465  * @min_addr: the lower bound of the memory region to allocate (phys address)
1466  * @max_addr: the upper bound of the memory region to allocate (phys address)
1467  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1468  * @exact_nid: control the allocation fall back to other nodes
1469  *
1470  * Allocates memory block using memblock_alloc_range_nid() and
1471  * converts the returned physical address to virtual.
1472  *
1473  * The @min_addr limit is dropped if it can not be satisfied and the allocation
1474  * will fall back to memory below @min_addr. Other constraints, such
1475  * as node and mirrored memory will be handled again in
1476  * memblock_alloc_range_nid().
1477  *
1478  * Return:
1479  * Virtual address of allocated memory block on success, NULL on failure.
1480  */
1481 static void * __init memblock_alloc_internal(
1482 				phys_addr_t size, phys_addr_t align,
1483 				phys_addr_t min_addr, phys_addr_t max_addr,
1484 				int nid, bool exact_nid)
1485 {
1486 	phys_addr_t alloc;
1487 
1488 	/*
1489 	 * Detect any accidental use of these APIs after slab is ready, as at
1490 	 * this moment memblock may be deinitialized already and its
1491 	 * internal data may be destroyed (after execution of memblock_free_all)
1492 	 */
1493 	if (WARN_ON_ONCE(slab_is_available()))
1494 		return kzalloc_node(size, GFP_NOWAIT, nid);
1495 
1496 	if (max_addr > memblock.current_limit)
1497 		max_addr = memblock.current_limit;
1498 
1499 	alloc = memblock_alloc_range_nid(size, align, min_addr, max_addr, nid,
1500 					exact_nid);
1501 
1502 	/* retry allocation without lower limit */
1503 	if (!alloc && min_addr)
1504 		alloc = memblock_alloc_range_nid(size, align, 0, max_addr, nid,
1505 						exact_nid);
1506 
1507 	if (!alloc)
1508 		return NULL;
1509 
1510 	return phys_to_virt(alloc);
1511 }
1512 
1513 /**
1514  * memblock_alloc_exact_nid_raw - allocate boot memory block on the exact node
1515  * without zeroing memory
1516  * @size: size of memory block to be allocated in bytes
1517  * @align: alignment of the region and block's size
1518  * @min_addr: the lower bound of the memory region from where the allocation
1519  *	  is preferred (phys address)
1520  * @max_addr: the upper bound of the memory region from where the allocation
1521  *	      is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to
1522  *	      allocate only from memory limited by memblock.current_limit value
1523  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1524  *
1525  * Public function, provides additional debug information (including caller
1526  * info), if enabled. Does not zero allocated memory.
1527  *
1528  * Return:
1529  * Virtual address of allocated memory block on success, NULL on failure.
1530  */
1531 void * __init memblock_alloc_exact_nid_raw(
1532 			phys_addr_t size, phys_addr_t align,
1533 			phys_addr_t min_addr, phys_addr_t max_addr,
1534 			int nid)
1535 {
1536 	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
1537 		     __func__, (u64)size, (u64)align, nid, &min_addr,
1538 		     &max_addr, (void *)_RET_IP_);
1539 
1540 	return memblock_alloc_internal(size, align, min_addr, max_addr, nid,
1541 				       true);
1542 }
1543 
1544 /**
1545  * memblock_alloc_try_nid_raw - allocate boot memory block without zeroing
1546  * memory and without panicking
1547  * @size: size of memory block to be allocated in bytes
1548  * @align: alignment of the region and block's size
1549  * @min_addr: the lower bound of the memory region from where the allocation
1550  *	  is preferred (phys address)
1551  * @max_addr: the upper bound of the memory region from where the allocation
1552  *	      is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to
1553  *	      allocate only from memory limited by memblock.current_limit value
1554  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1555  *
1556  * Public function, provides additional debug information (including caller
1557  * info), if enabled. Does not zero allocated memory, does not panic if request
1558  * cannot be satisfied.
1559  *
1560  * Return:
1561  * Virtual address of allocated memory block on success, NULL on failure.
1562  */
1563 void * __init memblock_alloc_try_nid_raw(
1564 			phys_addr_t size, phys_addr_t align,
1565 			phys_addr_t min_addr, phys_addr_t max_addr,
1566 			int nid)
1567 {
1568 	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
1569 		     __func__, (u64)size, (u64)align, nid, &min_addr,
1570 		     &max_addr, (void *)_RET_IP_);
1571 
1572 	return memblock_alloc_internal(size, align, min_addr, max_addr, nid,
1573 				       false);
1574 }
1575 
1576 /**
1577  * memblock_alloc_try_nid - allocate boot memory block
1578  * @size: size of memory block to be allocated in bytes
1579  * @align: alignment of the region and block's size
1580  * @min_addr: the lower bound of the memory region from where the allocation
1581  *	  is preferred (phys address)
1582  * @max_addr: the upper bound of the memory region from where the allocation
1583  *	      is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to
1584  *	      allocate only from memory limited by memblock.current_limit value
1585  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1586  *
1587  * Public function, provides additional debug information (including caller
1588  * info), if enabled. This function zeroes the allocated memory.
1589  *
1590  * Return:
1591  * Virtual address of allocated memory block on success, NULL on failure.
1592  */
1593 void * __init memblock_alloc_try_nid(
1594 			phys_addr_t size, phys_addr_t align,
1595 			phys_addr_t min_addr, phys_addr_t max_addr,
1596 			int nid)
1597 {
1598 	void *ptr;
1599 
1600 	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
1601 		     __func__, (u64)size, (u64)align, nid, &min_addr,
1602 		     &max_addr, (void *)_RET_IP_);
1603 	ptr = memblock_alloc_internal(size, align,
1604 					   min_addr, max_addr, nid, false);
1605 	if (ptr)
1606 		memset(ptr, 0, size);
1607 
1608 	return ptr;
1609 }
1610 
1611 /**
1612  * memblock_free_late - free pages directly to buddy allocator
1613  * @base: phys starting address of the  boot memory block
1614  * @size: size of the boot memory block in bytes
1615  *
1616  * This is only useful when the memblock allocator has already been torn
1617  * down, but we are still initializing the system.  Pages are released directly
1618  * to the buddy allocator.
1619  */
1620 void __init memblock_free_late(phys_addr_t base, phys_addr_t size)
1621 {
1622 	phys_addr_t cursor, end;
1623 
1624 	end = base + size - 1;
1625 	memblock_dbg("%s: [%pa-%pa] %pS\n",
1626 		     __func__, &base, &end, (void *)_RET_IP_);
1627 	kmemleak_free_part_phys(base, size);
1628 	cursor = PFN_UP(base);
1629 	end = PFN_DOWN(base + size);
1630 
1631 	for (; cursor < end; cursor++) {
1632 		memblock_free_pages(pfn_to_page(cursor), cursor, 0);
1633 		totalram_pages_inc();
1634 	}
1635 }
1636 
1637 /*
1638  * Remaining API functions
1639  */
1640 
1641 phys_addr_t __init_memblock memblock_phys_mem_size(void)
1642 {
1643 	return memblock.memory.total_size;
1644 }
1645 
1646 phys_addr_t __init_memblock memblock_reserved_size(void)
1647 {
1648 	return memblock.reserved.total_size;
1649 }
1650 
1651 /* lowest address */
1652 phys_addr_t __init_memblock memblock_start_of_DRAM(void)
1653 {
1654 	return memblock.memory.regions[0].base;
1655 }
1656 
1657 phys_addr_t __init_memblock memblock_end_of_DRAM(void)
1658 {
1659 	int idx = memblock.memory.cnt - 1;
1660 
1661 	return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
1662 }
1663 
1664 static phys_addr_t __init_memblock __find_max_addr(phys_addr_t limit)
1665 {
1666 	phys_addr_t max_addr = PHYS_ADDR_MAX;
1667 	struct memblock_region *r;
1668 
1669 	/*
1670 	 * translate the memory @limit size into the max address within one of
1671 	 * the memory memblock regions, if the @limit exceeds the total size
1672 	 * of those regions, max_addr will keep original value PHYS_ADDR_MAX
1673 	 */
1674 	for_each_mem_region(r) {
1675 		if (limit <= r->size) {
1676 			max_addr = r->base + limit;
1677 			break;
1678 		}
1679 		limit -= r->size;
1680 	}
1681 
1682 	return max_addr;
1683 }
1684 
1685 void __init memblock_enforce_memory_limit(phys_addr_t limit)
1686 {
1687 	phys_addr_t max_addr;
1688 
1689 	if (!limit)
1690 		return;
1691 
1692 	max_addr = __find_max_addr(limit);
1693 
1694 	/* @limit exceeds the total size of the memory, do nothing */
1695 	if (max_addr == PHYS_ADDR_MAX)
1696 		return;
1697 
1698 	/* truncate both memory and reserved regions */
1699 	memblock_remove_range(&memblock.memory, max_addr,
1700 			      PHYS_ADDR_MAX);
1701 	memblock_remove_range(&memblock.reserved, max_addr,
1702 			      PHYS_ADDR_MAX);
1703 }
1704 
1705 void __init memblock_cap_memory_range(phys_addr_t base, phys_addr_t size)
1706 {
1707 	int start_rgn, end_rgn;
1708 	int i, ret;
1709 
1710 	if (!size)
1711 		return;
1712 
1713 	if (!memblock_memory->total_size) {
1714 		pr_warn("%s: No memory registered yet\n", __func__);
1715 		return;
1716 	}
1717 
1718 	ret = memblock_isolate_range(&memblock.memory, base, size,
1719 						&start_rgn, &end_rgn);
1720 	if (ret)
1721 		return;
1722 
1723 	/* remove all the MAP regions */
1724 	for (i = memblock.memory.cnt - 1; i >= end_rgn; i--)
1725 		if (!memblock_is_nomap(&memblock.memory.regions[i]))
1726 			memblock_remove_region(&memblock.memory, i);
1727 
1728 	for (i = start_rgn - 1; i >= 0; i--)
1729 		if (!memblock_is_nomap(&memblock.memory.regions[i]))
1730 			memblock_remove_region(&memblock.memory, i);
1731 
1732 	/* truncate the reserved regions */
1733 	memblock_remove_range(&memblock.reserved, 0, base);
1734 	memblock_remove_range(&memblock.reserved,
1735 			base + size, PHYS_ADDR_MAX);
1736 }
1737 
1738 void __init memblock_mem_limit_remove_map(phys_addr_t limit)
1739 {
1740 	phys_addr_t max_addr;
1741 
1742 	if (!limit)
1743 		return;
1744 
1745 	max_addr = __find_max_addr(limit);
1746 
1747 	/* @limit exceeds the total size of the memory, do nothing */
1748 	if (max_addr == PHYS_ADDR_MAX)
1749 		return;
1750 
1751 	memblock_cap_memory_range(0, max_addr);
1752 }
1753 
1754 static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
1755 {
1756 	unsigned int left = 0, right = type->cnt;
1757 
1758 	do {
1759 		unsigned int mid = (right + left) / 2;
1760 
1761 		if (addr < type->regions[mid].base)
1762 			right = mid;
1763 		else if (addr >= (type->regions[mid].base +
1764 				  type->regions[mid].size))
1765 			left = mid + 1;
1766 		else
1767 			return mid;
1768 	} while (left < right);
1769 	return -1;
1770 }
1771 
1772 bool __init_memblock memblock_is_reserved(phys_addr_t addr)
1773 {
1774 	return memblock_search(&memblock.reserved, addr) != -1;
1775 }
1776 
1777 bool __init_memblock memblock_is_memory(phys_addr_t addr)
1778 {
1779 	return memblock_search(&memblock.memory, addr) != -1;
1780 }
1781 
1782 bool __init_memblock memblock_is_map_memory(phys_addr_t addr)
1783 {
1784 	int i = memblock_search(&memblock.memory, addr);
1785 
1786 	if (i == -1)
1787 		return false;
1788 	return !memblock_is_nomap(&memblock.memory.regions[i]);
1789 }
1790 
1791 int __init_memblock memblock_search_pfn_nid(unsigned long pfn,
1792 			 unsigned long *start_pfn, unsigned long *end_pfn)
1793 {
1794 	struct memblock_type *type = &memblock.memory;
1795 	int mid = memblock_search(type, PFN_PHYS(pfn));
1796 
1797 	if (mid == -1)
1798 		return -1;
1799 
1800 	*start_pfn = PFN_DOWN(type->regions[mid].base);
1801 	*end_pfn = PFN_DOWN(type->regions[mid].base + type->regions[mid].size);
1802 
1803 	return memblock_get_region_node(&type->regions[mid]);
1804 }
1805 
1806 /**
1807  * memblock_is_region_memory - check if a region is a subset of memory
1808  * @base: base of region to check
1809  * @size: size of region to check
1810  *
1811  * Check if the region [@base, @base + @size) is a subset of a memory block.
1812  *
1813  * Return:
1814  * 0 if false, non-zero if true
1815  */
1816 bool __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
1817 {
1818 	int idx = memblock_search(&memblock.memory, base);
1819 	phys_addr_t end = base + memblock_cap_size(base, &size);
1820 
1821 	if (idx == -1)
1822 		return false;
1823 	return (memblock.memory.regions[idx].base +
1824 		 memblock.memory.regions[idx].size) >= end;
1825 }
1826 
1827 /**
1828  * memblock_is_region_reserved - check if a region intersects reserved memory
1829  * @base: base of region to check
1830  * @size: size of region to check
1831  *
1832  * Check if the region [@base, @base + @size) intersects a reserved
1833  * memory block.
1834  *
1835  * Return:
1836  * True if they intersect, false if not.
1837  */
1838 bool __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
1839 {
1840 	return memblock_overlaps_region(&memblock.reserved, base, size);
1841 }
1842 
1843 void __init_memblock memblock_trim_memory(phys_addr_t align)
1844 {
1845 	phys_addr_t start, end, orig_start, orig_end;
1846 	struct memblock_region *r;
1847 
1848 	for_each_mem_region(r) {
1849 		orig_start = r->base;
1850 		orig_end = r->base + r->size;
1851 		start = round_up(orig_start, align);
1852 		end = round_down(orig_end, align);
1853 
1854 		if (start == orig_start && end == orig_end)
1855 			continue;
1856 
1857 		if (start < end) {
1858 			r->base = start;
1859 			r->size = end - start;
1860 		} else {
1861 			memblock_remove_region(&memblock.memory,
1862 					       r - memblock.memory.regions);
1863 			r--;
1864 		}
1865 	}
1866 }
1867 
1868 void __init_memblock memblock_set_current_limit(phys_addr_t limit)
1869 {
1870 	memblock.current_limit = limit;
1871 }
1872 
1873 phys_addr_t __init_memblock memblock_get_current_limit(void)
1874 {
1875 	return memblock.current_limit;
1876 }
1877 
1878 static void __init_memblock memblock_dump(struct memblock_type *type)
1879 {
1880 	phys_addr_t base, end, size;
1881 	enum memblock_flags flags;
1882 	int idx;
1883 	struct memblock_region *rgn;
1884 
1885 	pr_info(" %s.cnt  = 0x%lx\n", type->name, type->cnt);
1886 
1887 	for_each_memblock_type(idx, type, rgn) {
1888 		char nid_buf[32] = "";
1889 
1890 		base = rgn->base;
1891 		size = rgn->size;
1892 		end = base + size - 1;
1893 		flags = rgn->flags;
1894 #ifdef CONFIG_NUMA
1895 		if (memblock_get_region_node(rgn) != MAX_NUMNODES)
1896 			snprintf(nid_buf, sizeof(nid_buf), " on node %d",
1897 				 memblock_get_region_node(rgn));
1898 #endif
1899 		pr_info(" %s[%#x]\t[%pa-%pa], %pa bytes%s flags: %#x\n",
1900 			type->name, idx, &base, &end, &size, nid_buf, flags);
1901 	}
1902 }
1903 
1904 static void __init_memblock __memblock_dump_all(void)
1905 {
1906 	pr_info("MEMBLOCK configuration:\n");
1907 	pr_info(" memory size = %pa reserved size = %pa\n",
1908 		&memblock.memory.total_size,
1909 		&memblock.reserved.total_size);
1910 
1911 	memblock_dump(&memblock.memory);
1912 	memblock_dump(&memblock.reserved);
1913 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
1914 	memblock_dump(&physmem);
1915 #endif
1916 }
1917 
1918 void __init_memblock memblock_dump_all(void)
1919 {
1920 	if (memblock_debug)
1921 		__memblock_dump_all();
1922 }
1923 
1924 void __init memblock_allow_resize(void)
1925 {
1926 	memblock_can_resize = 1;
1927 }
1928 
1929 static int __init early_memblock(char *p)
1930 {
1931 	if (p && strstr(p, "debug"))
1932 		memblock_debug = 1;
1933 	return 0;
1934 }
1935 early_param("memblock", early_memblock);
1936 
1937 static void __init free_memmap(unsigned long start_pfn, unsigned long end_pfn)
1938 {
1939 	struct page *start_pg, *end_pg;
1940 	phys_addr_t pg, pgend;
1941 
1942 	/*
1943 	 * Convert start_pfn/end_pfn to a struct page pointer.
1944 	 */
1945 	start_pg = pfn_to_page(start_pfn - 1) + 1;
1946 	end_pg = pfn_to_page(end_pfn - 1) + 1;
1947 
1948 	/*
1949 	 * Convert to physical addresses, and round start upwards and end
1950 	 * downwards.
1951 	 */
1952 	pg = PAGE_ALIGN(__pa(start_pg));
1953 	pgend = __pa(end_pg) & PAGE_MASK;
1954 
1955 	/*
1956 	 * If there are free pages between these, free the section of the
1957 	 * memmap array.
1958 	 */
1959 	if (pg < pgend)
1960 		memblock_phys_free(pg, pgend - pg);
1961 }
1962 
1963 /*
1964  * The mem_map array can get very big.  Free the unused area of the memory map.
1965  */
1966 static void __init free_unused_memmap(void)
1967 {
1968 	unsigned long start, end, prev_end = 0;
1969 	int i;
1970 
1971 	if (!IS_ENABLED(CONFIG_HAVE_ARCH_PFN_VALID) ||
1972 	    IS_ENABLED(CONFIG_SPARSEMEM_VMEMMAP))
1973 		return;
1974 
1975 	/*
1976 	 * This relies on each bank being in address order.
1977 	 * The banks are sorted previously in bootmem_init().
1978 	 */
1979 	for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, NULL) {
1980 #ifdef CONFIG_SPARSEMEM
1981 		/*
1982 		 * Take care not to free memmap entries that don't exist
1983 		 * due to SPARSEMEM sections which aren't present.
1984 		 */
1985 		start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
1986 #endif
1987 		/*
1988 		 * Align down here since many operations in VM subsystem
1989 		 * presume that there are no holes in the memory map inside
1990 		 * a pageblock
1991 		 */
1992 		start = round_down(start, pageblock_nr_pages);
1993 
1994 		/*
1995 		 * If we had a previous bank, and there is a space
1996 		 * between the current bank and the previous, free it.
1997 		 */
1998 		if (prev_end && prev_end < start)
1999 			free_memmap(prev_end, start);
2000 
2001 		/*
2002 		 * Align up here since many operations in VM subsystem
2003 		 * presume that there are no holes in the memory map inside
2004 		 * a pageblock
2005 		 */
2006 		prev_end = ALIGN(end, pageblock_nr_pages);
2007 	}
2008 
2009 #ifdef CONFIG_SPARSEMEM
2010 	if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION)) {
2011 		prev_end = ALIGN(end, pageblock_nr_pages);
2012 		free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
2013 	}
2014 #endif
2015 }
2016 
2017 static void __init __free_pages_memory(unsigned long start, unsigned long end)
2018 {
2019 	int order;
2020 
2021 	while (start < end) {
2022 		order = min(MAX_ORDER - 1UL, __ffs(start));
2023 
2024 		while (start + (1UL << order) > end)
2025 			order--;
2026 
2027 		memblock_free_pages(pfn_to_page(start), start, order);
2028 
2029 		start += (1UL << order);
2030 	}
2031 }
2032 
2033 static unsigned long __init __free_memory_core(phys_addr_t start,
2034 				 phys_addr_t end)
2035 {
2036 	unsigned long start_pfn = PFN_UP(start);
2037 	unsigned long end_pfn = min_t(unsigned long,
2038 				      PFN_DOWN(end), max_low_pfn);
2039 
2040 	if (start_pfn >= end_pfn)
2041 		return 0;
2042 
2043 	__free_pages_memory(start_pfn, end_pfn);
2044 
2045 	return end_pfn - start_pfn;
2046 }
2047 
2048 static void __init memmap_init_reserved_pages(void)
2049 {
2050 	struct memblock_region *region;
2051 	phys_addr_t start, end;
2052 	u64 i;
2053 
2054 	/* initialize struct pages for the reserved regions */
2055 	for_each_reserved_mem_range(i, &start, &end)
2056 		reserve_bootmem_region(start, end);
2057 
2058 	/* and also treat struct pages for the NOMAP regions as PageReserved */
2059 	for_each_mem_region(region) {
2060 		if (memblock_is_nomap(region)) {
2061 			start = region->base;
2062 			end = start + region->size;
2063 			reserve_bootmem_region(start, end);
2064 		}
2065 	}
2066 }
2067 
2068 static unsigned long __init free_low_memory_core_early(void)
2069 {
2070 	unsigned long count = 0;
2071 	phys_addr_t start, end;
2072 	u64 i;
2073 
2074 	memblock_clear_hotplug(0, -1);
2075 
2076 	memmap_init_reserved_pages();
2077 
2078 	/*
2079 	 * We need to use NUMA_NO_NODE instead of NODE_DATA(0)->node_id
2080 	 *  because in some case like Node0 doesn't have RAM installed
2081 	 *  low ram will be on Node1
2082 	 */
2083 	for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE, &start, &end,
2084 				NULL)
2085 		count += __free_memory_core(start, end);
2086 
2087 	return count;
2088 }
2089 
2090 static int reset_managed_pages_done __initdata;
2091 
2092 void reset_node_managed_pages(pg_data_t *pgdat)
2093 {
2094 	struct zone *z;
2095 
2096 	for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
2097 		atomic_long_set(&z->managed_pages, 0);
2098 }
2099 
2100 void __init reset_all_zones_managed_pages(void)
2101 {
2102 	struct pglist_data *pgdat;
2103 
2104 	if (reset_managed_pages_done)
2105 		return;
2106 
2107 	for_each_online_pgdat(pgdat)
2108 		reset_node_managed_pages(pgdat);
2109 
2110 	reset_managed_pages_done = 1;
2111 }
2112 
2113 /**
2114  * memblock_free_all - release free pages to the buddy allocator
2115  */
2116 void __init memblock_free_all(void)
2117 {
2118 	unsigned long pages;
2119 
2120 	free_unused_memmap();
2121 	reset_all_zones_managed_pages();
2122 
2123 	pages = free_low_memory_core_early();
2124 	totalram_pages_add(pages);
2125 }
2126 
2127 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_ARCH_KEEP_MEMBLOCK)
2128 
2129 static int memblock_debug_show(struct seq_file *m, void *private)
2130 {
2131 	struct memblock_type *type = m->private;
2132 	struct memblock_region *reg;
2133 	int i;
2134 	phys_addr_t end;
2135 
2136 	for (i = 0; i < type->cnt; i++) {
2137 		reg = &type->regions[i];
2138 		end = reg->base + reg->size - 1;
2139 
2140 		seq_printf(m, "%4d: ", i);
2141 		seq_printf(m, "%pa..%pa\n", &reg->base, &end);
2142 	}
2143 	return 0;
2144 }
2145 DEFINE_SHOW_ATTRIBUTE(memblock_debug);
2146 
2147 static int __init memblock_init_debugfs(void)
2148 {
2149 	struct dentry *root = debugfs_create_dir("memblock", NULL);
2150 
2151 	debugfs_create_file("memory", 0444, root,
2152 			    &memblock.memory, &memblock_debug_fops);
2153 	debugfs_create_file("reserved", 0444, root,
2154 			    &memblock.reserved, &memblock_debug_fops);
2155 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
2156 	debugfs_create_file("physmem", 0444, root, &physmem,
2157 			    &memblock_debug_fops);
2158 #endif
2159 
2160 	return 0;
2161 }
2162 __initcall(memblock_init_debugfs);
2163 
2164 #endif /* CONFIG_DEBUG_FS */
2165