xref: /openbmc/linux/mm/memblock.c (revision 79e790ff)
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 /**
33  * DOC: memblock overview
34  *
35  * Memblock is a method of managing memory regions during the early
36  * boot period when the usual kernel memory allocators are not up and
37  * running.
38  *
39  * Memblock views the system memory as collections of contiguous
40  * regions. There are several types of these collections:
41  *
42  * * ``memory`` - describes the physical memory available to the
43  *   kernel; this may differ from the actual physical memory installed
44  *   in the system, for instance when the memory is restricted with
45  *   ``mem=`` command line parameter
46  * * ``reserved`` - describes the regions that were allocated
47  * * ``physmem`` - describes the actual physical memory available during
48  *   boot regardless of the possible restrictions and memory hot(un)plug;
49  *   the ``physmem`` type is only available on some architectures.
50  *
51  * Each region is represented by struct memblock_region that
52  * defines the region extents, its attributes and NUMA node id on NUMA
53  * systems. Every memory type is described by the struct memblock_type
54  * which contains an array of memory regions along with
55  * the allocator metadata. The "memory" and "reserved" types are nicely
56  * wrapped with struct memblock. This structure is statically
57  * initialized at build time. The region arrays are initially sized to
58  * %INIT_MEMBLOCK_REGIONS for "memory" and %INIT_MEMBLOCK_RESERVED_REGIONS
59  * for "reserved". The region array for "physmem" is initially sized to
60  * %INIT_PHYSMEM_REGIONS.
61  * The memblock_allow_resize() enables automatic resizing of the region
62  * arrays during addition of new regions. This feature should be used
63  * with care so that memory allocated for the region array will not
64  * overlap with areas that should be reserved, for example initrd.
65  *
66  * The early architecture setup should tell memblock what the physical
67  * memory layout is by using memblock_add() or memblock_add_node()
68  * functions. The first function does not assign the region to a NUMA
69  * node and it is appropriate for UMA systems. Yet, it is possible to
70  * use it on NUMA systems as well and assign the region to a NUMA node
71  * later in the setup process using memblock_set_node(). The
72  * memblock_add_node() performs such an assignment directly.
73  *
74  * Once memblock is setup the memory can be allocated using one of the
75  * API variants:
76  *
77  * * memblock_phys_alloc*() - these functions return the **physical**
78  *   address of the allocated memory
79  * * memblock_alloc*() - these functions return the **virtual** address
80  *   of the allocated memory.
81  *
82  * Note, that both API variants use implicit assumptions about allowed
83  * memory ranges and the fallback methods. Consult the documentation
84  * of memblock_alloc_internal() and memblock_alloc_range_nid()
85  * functions for more elaborate description.
86  *
87  * As the system boot progresses, the architecture specific mem_init()
88  * function frees all the memory to the buddy page allocator.
89  *
90  * Unless an architecture enables %CONFIG_ARCH_KEEP_MEMBLOCK, the
91  * memblock data structures (except "physmem") will be discarded after the
92  * system initialization completes.
93  */
94 
95 #ifndef CONFIG_NEED_MULTIPLE_NODES
96 struct pglist_data __refdata contig_page_data;
97 EXPORT_SYMBOL(contig_page_data);
98 #endif
99 
100 unsigned long max_low_pfn;
101 unsigned long min_low_pfn;
102 unsigned long max_pfn;
103 unsigned long long max_possible_pfn;
104 
105 static struct memblock_region memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS] __initdata_memblock;
106 static struct memblock_region memblock_reserved_init_regions[INIT_MEMBLOCK_RESERVED_REGIONS] __initdata_memblock;
107 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
108 static struct memblock_region memblock_physmem_init_regions[INIT_PHYSMEM_REGIONS];
109 #endif
110 
111 struct memblock memblock __initdata_memblock = {
112 	.memory.regions		= memblock_memory_init_regions,
113 	.memory.cnt		= 1,	/* empty dummy entry */
114 	.memory.max		= INIT_MEMBLOCK_REGIONS,
115 	.memory.name		= "memory",
116 
117 	.reserved.regions	= memblock_reserved_init_regions,
118 	.reserved.cnt		= 1,	/* empty dummy entry */
119 	.reserved.max		= INIT_MEMBLOCK_RESERVED_REGIONS,
120 	.reserved.name		= "reserved",
121 
122 	.bottom_up		= false,
123 	.current_limit		= MEMBLOCK_ALLOC_ANYWHERE,
124 };
125 
126 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
127 struct memblock_type physmem = {
128 	.regions		= memblock_physmem_init_regions,
129 	.cnt			= 1,	/* empty dummy entry */
130 	.max			= INIT_PHYSMEM_REGIONS,
131 	.name			= "physmem",
132 };
133 #endif
134 
135 /*
136  * keep a pointer to &memblock.memory in the text section to use it in
137  * __next_mem_range() and its helpers.
138  *  For architectures that do not keep memblock data after init, this
139  * pointer will be reset to NULL at memblock_discard()
140  */
141 static __refdata struct memblock_type *memblock_memory = &memblock.memory;
142 
143 #define for_each_memblock_type(i, memblock_type, rgn)			\
144 	for (i = 0, rgn = &memblock_type->regions[0];			\
145 	     i < memblock_type->cnt;					\
146 	     i++, rgn = &memblock_type->regions[i])
147 
148 #define memblock_dbg(fmt, ...)						\
149 	do {								\
150 		if (memblock_debug)					\
151 			pr_info(fmt, ##__VA_ARGS__);			\
152 	} while (0)
153 
154 static int memblock_debug __initdata_memblock;
155 static bool system_has_some_mirror __initdata_memblock = false;
156 static int memblock_can_resize __initdata_memblock;
157 static int memblock_memory_in_slab __initdata_memblock = 0;
158 static int memblock_reserved_in_slab __initdata_memblock = 0;
159 
160 static enum memblock_flags __init_memblock choose_memblock_flags(void)
161 {
162 	return system_has_some_mirror ? MEMBLOCK_MIRROR : MEMBLOCK_NONE;
163 }
164 
165 /* adjust *@size so that (@base + *@size) doesn't overflow, return new size */
166 static inline phys_addr_t memblock_cap_size(phys_addr_t base, phys_addr_t *size)
167 {
168 	return *size = min(*size, PHYS_ADDR_MAX - base);
169 }
170 
171 /*
172  * Address comparison utilities
173  */
174 static unsigned long __init_memblock memblock_addrs_overlap(phys_addr_t base1, phys_addr_t size1,
175 				       phys_addr_t base2, phys_addr_t size2)
176 {
177 	return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
178 }
179 
180 bool __init_memblock memblock_overlaps_region(struct memblock_type *type,
181 					phys_addr_t base, phys_addr_t size)
182 {
183 	unsigned long i;
184 
185 	for (i = 0; i < type->cnt; i++)
186 		if (memblock_addrs_overlap(base, size, type->regions[i].base,
187 					   type->regions[i].size))
188 			break;
189 	return i < type->cnt;
190 }
191 
192 /**
193  * __memblock_find_range_bottom_up - find free area utility in bottom-up
194  * @start: start of candidate range
195  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
196  *       %MEMBLOCK_ALLOC_ACCESSIBLE
197  * @size: size of free area to find
198  * @align: alignment of free area to find
199  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
200  * @flags: pick from blocks based on memory attributes
201  *
202  * Utility called from memblock_find_in_range_node(), find free area bottom-up.
203  *
204  * Return:
205  * Found address on success, 0 on failure.
206  */
207 static phys_addr_t __init_memblock
208 __memblock_find_range_bottom_up(phys_addr_t start, phys_addr_t end,
209 				phys_addr_t size, phys_addr_t align, int nid,
210 				enum memblock_flags flags)
211 {
212 	phys_addr_t this_start, this_end, cand;
213 	u64 i;
214 
215 	for_each_free_mem_range(i, nid, flags, &this_start, &this_end, NULL) {
216 		this_start = clamp(this_start, start, end);
217 		this_end = clamp(this_end, start, end);
218 
219 		cand = round_up(this_start, align);
220 		if (cand < this_end && this_end - cand >= size)
221 			return cand;
222 	}
223 
224 	return 0;
225 }
226 
227 /**
228  * __memblock_find_range_top_down - find free area utility, in top-down
229  * @start: start of candidate range
230  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
231  *       %MEMBLOCK_ALLOC_ACCESSIBLE
232  * @size: size of free area to find
233  * @align: alignment of free area to find
234  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
235  * @flags: pick from blocks based on memory attributes
236  *
237  * Utility called from memblock_find_in_range_node(), find free area top-down.
238  *
239  * Return:
240  * Found address on success, 0 on failure.
241  */
242 static phys_addr_t __init_memblock
243 __memblock_find_range_top_down(phys_addr_t start, phys_addr_t end,
244 			       phys_addr_t size, phys_addr_t align, int nid,
245 			       enum memblock_flags flags)
246 {
247 	phys_addr_t this_start, this_end, cand;
248 	u64 i;
249 
250 	for_each_free_mem_range_reverse(i, nid, flags, &this_start, &this_end,
251 					NULL) {
252 		this_start = clamp(this_start, start, end);
253 		this_end = clamp(this_end, start, end);
254 
255 		if (this_end < size)
256 			continue;
257 
258 		cand = round_down(this_end - size, align);
259 		if (cand >= this_start)
260 			return cand;
261 	}
262 
263 	return 0;
264 }
265 
266 /**
267  * memblock_find_in_range_node - find free area in given range and node
268  * @size: size of free area to find
269  * @align: alignment of free area to find
270  * @start: start of candidate range
271  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
272  *       %MEMBLOCK_ALLOC_ACCESSIBLE
273  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
274  * @flags: pick from blocks based on memory attributes
275  *
276  * Find @size free area aligned to @align in the specified range and node.
277  *
278  * Return:
279  * Found address on success, 0 on failure.
280  */
281 static phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t size,
282 					phys_addr_t align, phys_addr_t start,
283 					phys_addr_t end, int nid,
284 					enum memblock_flags flags)
285 {
286 	/* pump up @end */
287 	if (end == MEMBLOCK_ALLOC_ACCESSIBLE ||
288 	    end == MEMBLOCK_ALLOC_KASAN)
289 		end = memblock.current_limit;
290 
291 	/* avoid allocating the first page */
292 	start = max_t(phys_addr_t, start, PAGE_SIZE);
293 	end = max(start, end);
294 
295 	if (memblock_bottom_up())
296 		return __memblock_find_range_bottom_up(start, end, size, align,
297 						       nid, flags);
298 	else
299 		return __memblock_find_range_top_down(start, end, size, align,
300 						      nid, flags);
301 }
302 
303 /**
304  * memblock_find_in_range - find free area in given range
305  * @start: start of candidate range
306  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
307  *       %MEMBLOCK_ALLOC_ACCESSIBLE
308  * @size: size of free area to find
309  * @align: alignment of free area to find
310  *
311  * Find @size free area aligned to @align in the specified range.
312  *
313  * Return:
314  * Found address on success, 0 on failure.
315  */
316 phys_addr_t __init_memblock memblock_find_in_range(phys_addr_t start,
317 					phys_addr_t end, phys_addr_t size,
318 					phys_addr_t align)
319 {
320 	phys_addr_t ret;
321 	enum memblock_flags flags = choose_memblock_flags();
322 
323 again:
324 	ret = memblock_find_in_range_node(size, align, start, end,
325 					    NUMA_NO_NODE, flags);
326 
327 	if (!ret && (flags & MEMBLOCK_MIRROR)) {
328 		pr_warn("Could not allocate %pap bytes of mirrored memory\n",
329 			&size);
330 		flags &= ~MEMBLOCK_MIRROR;
331 		goto again;
332 	}
333 
334 	return ret;
335 }
336 
337 static void __init_memblock memblock_remove_region(struct memblock_type *type, unsigned long r)
338 {
339 	type->total_size -= type->regions[r].size;
340 	memmove(&type->regions[r], &type->regions[r + 1],
341 		(type->cnt - (r + 1)) * sizeof(type->regions[r]));
342 	type->cnt--;
343 
344 	/* Special case for empty arrays */
345 	if (type->cnt == 0) {
346 		WARN_ON(type->total_size != 0);
347 		type->cnt = 1;
348 		type->regions[0].base = 0;
349 		type->regions[0].size = 0;
350 		type->regions[0].flags = 0;
351 		memblock_set_region_node(&type->regions[0], MAX_NUMNODES);
352 	}
353 }
354 
355 #ifndef CONFIG_ARCH_KEEP_MEMBLOCK
356 /**
357  * memblock_discard - discard memory and reserved arrays if they were allocated
358  */
359 void __init memblock_discard(void)
360 {
361 	phys_addr_t addr, size;
362 
363 	if (memblock.reserved.regions != memblock_reserved_init_regions) {
364 		addr = __pa(memblock.reserved.regions);
365 		size = PAGE_ALIGN(sizeof(struct memblock_region) *
366 				  memblock.reserved.max);
367 		__memblock_free_late(addr, size);
368 	}
369 
370 	if (memblock.memory.regions != memblock_memory_init_regions) {
371 		addr = __pa(memblock.memory.regions);
372 		size = PAGE_ALIGN(sizeof(struct memblock_region) *
373 				  memblock.memory.max);
374 		__memblock_free_late(addr, size);
375 	}
376 
377 	memblock_memory = NULL;
378 }
379 #endif
380 
381 /**
382  * memblock_double_array - double the size of the memblock regions array
383  * @type: memblock type of the regions array being doubled
384  * @new_area_start: starting address of memory range to avoid overlap with
385  * @new_area_size: size of memory range to avoid overlap with
386  *
387  * Double the size of the @type regions array. If memblock is being used to
388  * allocate memory for a new reserved regions array and there is a previously
389  * allocated memory range [@new_area_start, @new_area_start + @new_area_size]
390  * waiting to be reserved, ensure the memory used by the new array does
391  * not overlap.
392  *
393  * Return:
394  * 0 on success, -1 on failure.
395  */
396 static int __init_memblock memblock_double_array(struct memblock_type *type,
397 						phys_addr_t new_area_start,
398 						phys_addr_t new_area_size)
399 {
400 	struct memblock_region *new_array, *old_array;
401 	phys_addr_t old_alloc_size, new_alloc_size;
402 	phys_addr_t old_size, new_size, addr, new_end;
403 	int use_slab = slab_is_available();
404 	int *in_slab;
405 
406 	/* We don't allow resizing until we know about the reserved regions
407 	 * of memory that aren't suitable for allocation
408 	 */
409 	if (!memblock_can_resize)
410 		return -1;
411 
412 	/* Calculate new doubled size */
413 	old_size = type->max * sizeof(struct memblock_region);
414 	new_size = old_size << 1;
415 	/*
416 	 * We need to allocated new one align to PAGE_SIZE,
417 	 *   so we can free them completely later.
418 	 */
419 	old_alloc_size = PAGE_ALIGN(old_size);
420 	new_alloc_size = PAGE_ALIGN(new_size);
421 
422 	/* Retrieve the slab flag */
423 	if (type == &memblock.memory)
424 		in_slab = &memblock_memory_in_slab;
425 	else
426 		in_slab = &memblock_reserved_in_slab;
427 
428 	/* Try to find some space for it */
429 	if (use_slab) {
430 		new_array = kmalloc(new_size, GFP_KERNEL);
431 		addr = new_array ? __pa(new_array) : 0;
432 	} else {
433 		/* only exclude range when trying to double reserved.regions */
434 		if (type != &memblock.reserved)
435 			new_area_start = new_area_size = 0;
436 
437 		addr = memblock_find_in_range(new_area_start + new_area_size,
438 						memblock.current_limit,
439 						new_alloc_size, PAGE_SIZE);
440 		if (!addr && new_area_size)
441 			addr = memblock_find_in_range(0,
442 				min(new_area_start, memblock.current_limit),
443 				new_alloc_size, PAGE_SIZE);
444 
445 		new_array = addr ? __va(addr) : NULL;
446 	}
447 	if (!addr) {
448 		pr_err("memblock: Failed to double %s array from %ld to %ld entries !\n",
449 		       type->name, type->max, type->max * 2);
450 		return -1;
451 	}
452 
453 	new_end = addr + new_size - 1;
454 	memblock_dbg("memblock: %s is doubled to %ld at [%pa-%pa]",
455 			type->name, type->max * 2, &addr, &new_end);
456 
457 	/*
458 	 * Found space, we now need to move the array over before we add the
459 	 * reserved region since it may be our reserved array itself that is
460 	 * full.
461 	 */
462 	memcpy(new_array, type->regions, old_size);
463 	memset(new_array + type->max, 0, old_size);
464 	old_array = type->regions;
465 	type->regions = new_array;
466 	type->max <<= 1;
467 
468 	/* Free old array. We needn't free it if the array is the static one */
469 	if (*in_slab)
470 		kfree(old_array);
471 	else if (old_array != memblock_memory_init_regions &&
472 		 old_array != memblock_reserved_init_regions)
473 		memblock_free(__pa(old_array), old_alloc_size);
474 
475 	/*
476 	 * Reserve the new array if that comes from the memblock.  Otherwise, we
477 	 * needn't do it
478 	 */
479 	if (!use_slab)
480 		BUG_ON(memblock_reserve(addr, new_alloc_size));
481 
482 	/* Update slab flag */
483 	*in_slab = use_slab;
484 
485 	return 0;
486 }
487 
488 /**
489  * memblock_merge_regions - merge neighboring compatible regions
490  * @type: memblock type to scan
491  *
492  * Scan @type and merge neighboring compatible regions.
493  */
494 static void __init_memblock memblock_merge_regions(struct memblock_type *type)
495 {
496 	int i = 0;
497 
498 	/* cnt never goes below 1 */
499 	while (i < type->cnt - 1) {
500 		struct memblock_region *this = &type->regions[i];
501 		struct memblock_region *next = &type->regions[i + 1];
502 
503 		if (this->base + this->size != next->base ||
504 		    memblock_get_region_node(this) !=
505 		    memblock_get_region_node(next) ||
506 		    this->flags != next->flags) {
507 			BUG_ON(this->base + this->size > next->base);
508 			i++;
509 			continue;
510 		}
511 
512 		this->size += next->size;
513 		/* move forward from next + 1, index of which is i + 2 */
514 		memmove(next, next + 1, (type->cnt - (i + 2)) * sizeof(*next));
515 		type->cnt--;
516 	}
517 }
518 
519 /**
520  * memblock_insert_region - insert new memblock region
521  * @type:	memblock type to insert into
522  * @idx:	index for the insertion point
523  * @base:	base address of the new region
524  * @size:	size of the new region
525  * @nid:	node id of the new region
526  * @flags:	flags of the new region
527  *
528  * Insert new memblock region [@base, @base + @size) into @type at @idx.
529  * @type must already have extra room to accommodate the new region.
530  */
531 static void __init_memblock memblock_insert_region(struct memblock_type *type,
532 						   int idx, phys_addr_t base,
533 						   phys_addr_t size,
534 						   int nid,
535 						   enum memblock_flags flags)
536 {
537 	struct memblock_region *rgn = &type->regions[idx];
538 
539 	BUG_ON(type->cnt >= type->max);
540 	memmove(rgn + 1, rgn, (type->cnt - idx) * sizeof(*rgn));
541 	rgn->base = base;
542 	rgn->size = size;
543 	rgn->flags = flags;
544 	memblock_set_region_node(rgn, nid);
545 	type->cnt++;
546 	type->total_size += size;
547 }
548 
549 /**
550  * memblock_add_range - add new memblock region
551  * @type: memblock type to add new region into
552  * @base: base address of the new region
553  * @size: size of the new region
554  * @nid: nid of the new region
555  * @flags: flags of the new region
556  *
557  * Add new memblock region [@base, @base + @size) into @type.  The new region
558  * is allowed to overlap with existing ones - overlaps don't affect already
559  * existing regions.  @type is guaranteed to be minimal (all neighbouring
560  * compatible regions are merged) after the addition.
561  *
562  * Return:
563  * 0 on success, -errno on failure.
564  */
565 static int __init_memblock memblock_add_range(struct memblock_type *type,
566 				phys_addr_t base, phys_addr_t size,
567 				int nid, enum memblock_flags flags)
568 {
569 	bool insert = false;
570 	phys_addr_t obase = base;
571 	phys_addr_t end = base + memblock_cap_size(base, &size);
572 	int idx, nr_new;
573 	struct memblock_region *rgn;
574 
575 	if (!size)
576 		return 0;
577 
578 	/* special case for empty array */
579 	if (type->regions[0].size == 0) {
580 		WARN_ON(type->cnt != 1 || type->total_size);
581 		type->regions[0].base = base;
582 		type->regions[0].size = size;
583 		type->regions[0].flags = flags;
584 		memblock_set_region_node(&type->regions[0], nid);
585 		type->total_size = size;
586 		return 0;
587 	}
588 repeat:
589 	/*
590 	 * The following is executed twice.  Once with %false @insert and
591 	 * then with %true.  The first counts the number of regions needed
592 	 * to accommodate the new area.  The second actually inserts them.
593 	 */
594 	base = obase;
595 	nr_new = 0;
596 
597 	for_each_memblock_type(idx, type, rgn) {
598 		phys_addr_t rbase = rgn->base;
599 		phys_addr_t rend = rbase + rgn->size;
600 
601 		if (rbase >= end)
602 			break;
603 		if (rend <= base)
604 			continue;
605 		/*
606 		 * @rgn overlaps.  If it separates the lower part of new
607 		 * area, insert that portion.
608 		 */
609 		if (rbase > base) {
610 #ifdef CONFIG_NEED_MULTIPLE_NODES
611 			WARN_ON(nid != memblock_get_region_node(rgn));
612 #endif
613 			WARN_ON(flags != rgn->flags);
614 			nr_new++;
615 			if (insert)
616 				memblock_insert_region(type, idx++, base,
617 						       rbase - base, nid,
618 						       flags);
619 		}
620 		/* area below @rend is dealt with, forget about it */
621 		base = min(rend, end);
622 	}
623 
624 	/* insert the remaining portion */
625 	if (base < end) {
626 		nr_new++;
627 		if (insert)
628 			memblock_insert_region(type, idx, base, end - base,
629 					       nid, flags);
630 	}
631 
632 	if (!nr_new)
633 		return 0;
634 
635 	/*
636 	 * If this was the first round, resize array and repeat for actual
637 	 * insertions; otherwise, merge and return.
638 	 */
639 	if (!insert) {
640 		while (type->cnt + nr_new > type->max)
641 			if (memblock_double_array(type, obase, size) < 0)
642 				return -ENOMEM;
643 		insert = true;
644 		goto repeat;
645 	} else {
646 		memblock_merge_regions(type);
647 		return 0;
648 	}
649 }
650 
651 /**
652  * memblock_add_node - add new memblock region within a NUMA node
653  * @base: base address of the new region
654  * @size: size of the new region
655  * @nid: nid of the new region
656  *
657  * Add new memblock region [@base, @base + @size) to the "memory"
658  * type. See memblock_add_range() description for mode details
659  *
660  * Return:
661  * 0 on success, -errno on failure.
662  */
663 int __init_memblock memblock_add_node(phys_addr_t base, phys_addr_t size,
664 				       int nid)
665 {
666 	return memblock_add_range(&memblock.memory, base, size, nid, 0);
667 }
668 
669 /**
670  * memblock_add - add new memblock region
671  * @base: base address of the new region
672  * @size: size of the new region
673  *
674  * Add new memblock region [@base, @base + @size) to the "memory"
675  * type. See memblock_add_range() description for mode details
676  *
677  * Return:
678  * 0 on success, -errno on failure.
679  */
680 int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
681 {
682 	phys_addr_t end = base + size - 1;
683 
684 	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
685 		     &base, &end, (void *)_RET_IP_);
686 
687 	return memblock_add_range(&memblock.memory, base, size, MAX_NUMNODES, 0);
688 }
689 
690 /**
691  * memblock_isolate_range - isolate given range into disjoint memblocks
692  * @type: memblock type to isolate range for
693  * @base: base of range to isolate
694  * @size: size of range to isolate
695  * @start_rgn: out parameter for the start of isolated region
696  * @end_rgn: out parameter for the end of isolated region
697  *
698  * Walk @type and ensure that regions don't cross the boundaries defined by
699  * [@base, @base + @size).  Crossing regions are split at the boundaries,
700  * which may create at most two more regions.  The index of the first
701  * region inside the range is returned in *@start_rgn and end in *@end_rgn.
702  *
703  * Return:
704  * 0 on success, -errno on failure.
705  */
706 static int __init_memblock memblock_isolate_range(struct memblock_type *type,
707 					phys_addr_t base, phys_addr_t size,
708 					int *start_rgn, int *end_rgn)
709 {
710 	phys_addr_t end = base + memblock_cap_size(base, &size);
711 	int idx;
712 	struct memblock_region *rgn;
713 
714 	*start_rgn = *end_rgn = 0;
715 
716 	if (!size)
717 		return 0;
718 
719 	/* we'll create at most two more regions */
720 	while (type->cnt + 2 > type->max)
721 		if (memblock_double_array(type, base, size) < 0)
722 			return -ENOMEM;
723 
724 	for_each_memblock_type(idx, type, rgn) {
725 		phys_addr_t rbase = rgn->base;
726 		phys_addr_t rend = rbase + rgn->size;
727 
728 		if (rbase >= end)
729 			break;
730 		if (rend <= base)
731 			continue;
732 
733 		if (rbase < base) {
734 			/*
735 			 * @rgn intersects from below.  Split and continue
736 			 * to process the next region - the new top half.
737 			 */
738 			rgn->base = base;
739 			rgn->size -= base - rbase;
740 			type->total_size -= base - rbase;
741 			memblock_insert_region(type, idx, rbase, base - rbase,
742 					       memblock_get_region_node(rgn),
743 					       rgn->flags);
744 		} else if (rend > end) {
745 			/*
746 			 * @rgn intersects from above.  Split and redo the
747 			 * current region - the new bottom half.
748 			 */
749 			rgn->base = end;
750 			rgn->size -= end - rbase;
751 			type->total_size -= end - rbase;
752 			memblock_insert_region(type, idx--, rbase, end - rbase,
753 					       memblock_get_region_node(rgn),
754 					       rgn->flags);
755 		} else {
756 			/* @rgn is fully contained, record it */
757 			if (!*end_rgn)
758 				*start_rgn = idx;
759 			*end_rgn = idx + 1;
760 		}
761 	}
762 
763 	return 0;
764 }
765 
766 static int __init_memblock memblock_remove_range(struct memblock_type *type,
767 					  phys_addr_t base, phys_addr_t size)
768 {
769 	int start_rgn, end_rgn;
770 	int i, ret;
771 
772 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
773 	if (ret)
774 		return ret;
775 
776 	for (i = end_rgn - 1; i >= start_rgn; i--)
777 		memblock_remove_region(type, i);
778 	return 0;
779 }
780 
781 int __init_memblock memblock_remove(phys_addr_t base, phys_addr_t size)
782 {
783 	phys_addr_t end = base + size - 1;
784 
785 	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
786 		     &base, &end, (void *)_RET_IP_);
787 
788 	return memblock_remove_range(&memblock.memory, base, size);
789 }
790 
791 /**
792  * memblock_free - free boot memory block
793  * @base: phys starting address of the  boot memory block
794  * @size: size of the boot memory block in bytes
795  *
796  * Free boot memory block previously allocated by memblock_alloc_xx() API.
797  * The freeing memory will not be released to the buddy allocator.
798  */
799 int __init_memblock memblock_free(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 	kmemleak_free_part_phys(base, size);
807 	return memblock_remove_range(&memblock.reserved, base, size);
808 }
809 
810 int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
811 {
812 	phys_addr_t end = base + size - 1;
813 
814 	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
815 		     &base, &end, (void *)_RET_IP_);
816 
817 	return memblock_add_range(&memblock.reserved, base, size, MAX_NUMNODES, 0);
818 }
819 
820 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
821 int __init_memblock memblock_physmem_add(phys_addr_t base, phys_addr_t size)
822 {
823 	phys_addr_t end = base + size - 1;
824 
825 	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
826 		     &base, &end, (void *)_RET_IP_);
827 
828 	return memblock_add_range(&physmem, base, size, MAX_NUMNODES, 0);
829 }
830 #endif
831 
832 /**
833  * memblock_setclr_flag - set or clear flag for a memory region
834  * @base: base address of the region
835  * @size: size of the region
836  * @set: set or clear the flag
837  * @flag: the flag to update
838  *
839  * This function isolates region [@base, @base + @size), and sets/clears flag
840  *
841  * Return: 0 on success, -errno on failure.
842  */
843 static int __init_memblock memblock_setclr_flag(phys_addr_t base,
844 				phys_addr_t size, int set, int flag)
845 {
846 	struct memblock_type *type = &memblock.memory;
847 	int i, ret, start_rgn, end_rgn;
848 
849 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
850 	if (ret)
851 		return ret;
852 
853 	for (i = start_rgn; i < end_rgn; i++) {
854 		struct memblock_region *r = &type->regions[i];
855 
856 		if (set)
857 			r->flags |= flag;
858 		else
859 			r->flags &= ~flag;
860 	}
861 
862 	memblock_merge_regions(type);
863 	return 0;
864 }
865 
866 /**
867  * memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
868  * @base: the base phys addr of the region
869  * @size: the size of the region
870  *
871  * Return: 0 on success, -errno on failure.
872  */
873 int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
874 {
875 	return memblock_setclr_flag(base, size, 1, MEMBLOCK_HOTPLUG);
876 }
877 
878 /**
879  * memblock_clear_hotplug - Clear flag MEMBLOCK_HOTPLUG for a specified region.
880  * @base: the base phys addr of the region
881  * @size: the size of the region
882  *
883  * Return: 0 on success, -errno on failure.
884  */
885 int __init_memblock memblock_clear_hotplug(phys_addr_t base, phys_addr_t size)
886 {
887 	return memblock_setclr_flag(base, size, 0, MEMBLOCK_HOTPLUG);
888 }
889 
890 /**
891  * memblock_mark_mirror - Mark mirrored memory with flag MEMBLOCK_MIRROR.
892  * @base: the base phys addr of the region
893  * @size: the size of the region
894  *
895  * Return: 0 on success, -errno on failure.
896  */
897 int __init_memblock memblock_mark_mirror(phys_addr_t base, phys_addr_t size)
898 {
899 	system_has_some_mirror = true;
900 
901 	return memblock_setclr_flag(base, size, 1, MEMBLOCK_MIRROR);
902 }
903 
904 /**
905  * memblock_mark_nomap - Mark a memory region with flag MEMBLOCK_NOMAP.
906  * @base: the base phys addr of the region
907  * @size: the size of the region
908  *
909  * Return: 0 on success, -errno on failure.
910  */
911 int __init_memblock memblock_mark_nomap(phys_addr_t base, phys_addr_t size)
912 {
913 	return memblock_setclr_flag(base, size, 1, MEMBLOCK_NOMAP);
914 }
915 
916 /**
917  * memblock_clear_nomap - Clear flag MEMBLOCK_NOMAP for a specified region.
918  * @base: the base phys addr of the region
919  * @size: the size of the region
920  *
921  * Return: 0 on success, -errno on failure.
922  */
923 int __init_memblock memblock_clear_nomap(phys_addr_t base, phys_addr_t size)
924 {
925 	return memblock_setclr_flag(base, size, 0, MEMBLOCK_NOMAP);
926 }
927 
928 static bool should_skip_region(struct memblock_type *type,
929 			       struct memblock_region *m,
930 			       int nid, int flags)
931 {
932 	int m_nid = memblock_get_region_node(m);
933 
934 	/* we never skip regions when iterating memblock.reserved or physmem */
935 	if (type != memblock_memory)
936 		return false;
937 
938 	/* only memory regions are associated with nodes, check it */
939 	if (nid != NUMA_NO_NODE && nid != m_nid)
940 		return true;
941 
942 	/* skip hotpluggable memory regions if needed */
943 	if (movable_node_is_enabled() && memblock_is_hotpluggable(m))
944 		return true;
945 
946 	/* if we want mirror memory skip non-mirror memory regions */
947 	if ((flags & MEMBLOCK_MIRROR) && !memblock_is_mirror(m))
948 		return true;
949 
950 	/* skip nomap memory unless we were asked for it explicitly */
951 	if (!(flags & MEMBLOCK_NOMAP) && memblock_is_nomap(m))
952 		return true;
953 
954 	return false;
955 }
956 
957 /**
958  * __next_mem_range - next function for for_each_free_mem_range() etc.
959  * @idx: pointer to u64 loop variable
960  * @nid: node selector, %NUMA_NO_NODE for all nodes
961  * @flags: pick from blocks based on memory attributes
962  * @type_a: pointer to memblock_type from where the range is taken
963  * @type_b: pointer to memblock_type which excludes memory from being taken
964  * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
965  * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
966  * @out_nid: ptr to int for nid of the range, can be %NULL
967  *
968  * Find the first area from *@idx which matches @nid, fill the out
969  * parameters, and update *@idx for the next iteration.  The lower 32bit of
970  * *@idx contains index into type_a and the upper 32bit indexes the
971  * areas before each region in type_b.	For example, if type_b regions
972  * look like the following,
973  *
974  *	0:[0-16), 1:[32-48), 2:[128-130)
975  *
976  * The upper 32bit indexes the following regions.
977  *
978  *	0:[0-0), 1:[16-32), 2:[48-128), 3:[130-MAX)
979  *
980  * As both region arrays are sorted, the function advances the two indices
981  * in lockstep and returns each intersection.
982  */
983 void __next_mem_range(u64 *idx, int nid, enum memblock_flags flags,
984 		      struct memblock_type *type_a,
985 		      struct memblock_type *type_b, phys_addr_t *out_start,
986 		      phys_addr_t *out_end, int *out_nid)
987 {
988 	int idx_a = *idx & 0xffffffff;
989 	int idx_b = *idx >> 32;
990 
991 	if (WARN_ONCE(nid == MAX_NUMNODES,
992 	"Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
993 		nid = NUMA_NO_NODE;
994 
995 	for (; idx_a < type_a->cnt; idx_a++) {
996 		struct memblock_region *m = &type_a->regions[idx_a];
997 
998 		phys_addr_t m_start = m->base;
999 		phys_addr_t m_end = m->base + m->size;
1000 		int	    m_nid = memblock_get_region_node(m);
1001 
1002 		if (should_skip_region(type_a, m, nid, flags))
1003 			continue;
1004 
1005 		if (!type_b) {
1006 			if (out_start)
1007 				*out_start = m_start;
1008 			if (out_end)
1009 				*out_end = m_end;
1010 			if (out_nid)
1011 				*out_nid = m_nid;
1012 			idx_a++;
1013 			*idx = (u32)idx_a | (u64)idx_b << 32;
1014 			return;
1015 		}
1016 
1017 		/* scan areas before each reservation */
1018 		for (; idx_b < type_b->cnt + 1; idx_b++) {
1019 			struct memblock_region *r;
1020 			phys_addr_t r_start;
1021 			phys_addr_t r_end;
1022 
1023 			r = &type_b->regions[idx_b];
1024 			r_start = idx_b ? r[-1].base + r[-1].size : 0;
1025 			r_end = idx_b < type_b->cnt ?
1026 				r->base : PHYS_ADDR_MAX;
1027 
1028 			/*
1029 			 * if idx_b advanced past idx_a,
1030 			 * break out to advance idx_a
1031 			 */
1032 			if (r_start >= m_end)
1033 				break;
1034 			/* if the two regions intersect, we're done */
1035 			if (m_start < r_end) {
1036 				if (out_start)
1037 					*out_start =
1038 						max(m_start, r_start);
1039 				if (out_end)
1040 					*out_end = min(m_end, r_end);
1041 				if (out_nid)
1042 					*out_nid = m_nid;
1043 				/*
1044 				 * The region which ends first is
1045 				 * advanced for the next iteration.
1046 				 */
1047 				if (m_end <= r_end)
1048 					idx_a++;
1049 				else
1050 					idx_b++;
1051 				*idx = (u32)idx_a | (u64)idx_b << 32;
1052 				return;
1053 			}
1054 		}
1055 	}
1056 
1057 	/* signal end of iteration */
1058 	*idx = ULLONG_MAX;
1059 }
1060 
1061 /**
1062  * __next_mem_range_rev - generic next function for for_each_*_range_rev()
1063  *
1064  * @idx: pointer to u64 loop variable
1065  * @nid: node selector, %NUMA_NO_NODE for all nodes
1066  * @flags: pick from blocks based on memory attributes
1067  * @type_a: pointer to memblock_type from where the range is taken
1068  * @type_b: pointer to memblock_type which excludes memory from being taken
1069  * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
1070  * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
1071  * @out_nid: ptr to int for nid of the range, can be %NULL
1072  *
1073  * Finds the next range from type_a which is not marked as unsuitable
1074  * in type_b.
1075  *
1076  * Reverse of __next_mem_range().
1077  */
1078 void __init_memblock __next_mem_range_rev(u64 *idx, int nid,
1079 					  enum memblock_flags flags,
1080 					  struct memblock_type *type_a,
1081 					  struct memblock_type *type_b,
1082 					  phys_addr_t *out_start,
1083 					  phys_addr_t *out_end, int *out_nid)
1084 {
1085 	int idx_a = *idx & 0xffffffff;
1086 	int idx_b = *idx >> 32;
1087 
1088 	if (WARN_ONCE(nid == MAX_NUMNODES, "Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
1089 		nid = NUMA_NO_NODE;
1090 
1091 	if (*idx == (u64)ULLONG_MAX) {
1092 		idx_a = type_a->cnt - 1;
1093 		if (type_b != NULL)
1094 			idx_b = type_b->cnt;
1095 		else
1096 			idx_b = 0;
1097 	}
1098 
1099 	for (; idx_a >= 0; idx_a--) {
1100 		struct memblock_region *m = &type_a->regions[idx_a];
1101 
1102 		phys_addr_t m_start = m->base;
1103 		phys_addr_t m_end = m->base + m->size;
1104 		int m_nid = memblock_get_region_node(m);
1105 
1106 		if (should_skip_region(type_a, m, nid, flags))
1107 			continue;
1108 
1109 		if (!type_b) {
1110 			if (out_start)
1111 				*out_start = m_start;
1112 			if (out_end)
1113 				*out_end = m_end;
1114 			if (out_nid)
1115 				*out_nid = m_nid;
1116 			idx_a--;
1117 			*idx = (u32)idx_a | (u64)idx_b << 32;
1118 			return;
1119 		}
1120 
1121 		/* scan areas before each reservation */
1122 		for (; idx_b >= 0; idx_b--) {
1123 			struct memblock_region *r;
1124 			phys_addr_t r_start;
1125 			phys_addr_t r_end;
1126 
1127 			r = &type_b->regions[idx_b];
1128 			r_start = idx_b ? r[-1].base + r[-1].size : 0;
1129 			r_end = idx_b < type_b->cnt ?
1130 				r->base : PHYS_ADDR_MAX;
1131 			/*
1132 			 * if idx_b advanced past idx_a,
1133 			 * break out to advance idx_a
1134 			 */
1135 
1136 			if (r_end <= m_start)
1137 				break;
1138 			/* if the two regions intersect, we're done */
1139 			if (m_end > r_start) {
1140 				if (out_start)
1141 					*out_start = max(m_start, r_start);
1142 				if (out_end)
1143 					*out_end = min(m_end, r_end);
1144 				if (out_nid)
1145 					*out_nid = m_nid;
1146 				if (m_start >= r_start)
1147 					idx_a--;
1148 				else
1149 					idx_b--;
1150 				*idx = (u32)idx_a | (u64)idx_b << 32;
1151 				return;
1152 			}
1153 		}
1154 	}
1155 	/* signal end of iteration */
1156 	*idx = ULLONG_MAX;
1157 }
1158 
1159 /*
1160  * Common iterator interface used to define for_each_mem_pfn_range().
1161  */
1162 void __init_memblock __next_mem_pfn_range(int *idx, int nid,
1163 				unsigned long *out_start_pfn,
1164 				unsigned long *out_end_pfn, int *out_nid)
1165 {
1166 	struct memblock_type *type = &memblock.memory;
1167 	struct memblock_region *r;
1168 	int r_nid;
1169 
1170 	while (++*idx < type->cnt) {
1171 		r = &type->regions[*idx];
1172 		r_nid = memblock_get_region_node(r);
1173 
1174 		if (PFN_UP(r->base) >= PFN_DOWN(r->base + r->size))
1175 			continue;
1176 		if (nid == MAX_NUMNODES || nid == r_nid)
1177 			break;
1178 	}
1179 	if (*idx >= type->cnt) {
1180 		*idx = -1;
1181 		return;
1182 	}
1183 
1184 	if (out_start_pfn)
1185 		*out_start_pfn = PFN_UP(r->base);
1186 	if (out_end_pfn)
1187 		*out_end_pfn = PFN_DOWN(r->base + r->size);
1188 	if (out_nid)
1189 		*out_nid = r_nid;
1190 }
1191 
1192 /**
1193  * memblock_set_node - set node ID on memblock regions
1194  * @base: base of area to set node ID for
1195  * @size: size of area to set node ID for
1196  * @type: memblock type to set node ID for
1197  * @nid: node ID to set
1198  *
1199  * Set the nid of memblock @type regions in [@base, @base + @size) to @nid.
1200  * Regions which cross the area boundaries are split as necessary.
1201  *
1202  * Return:
1203  * 0 on success, -errno on failure.
1204  */
1205 int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
1206 				      struct memblock_type *type, int nid)
1207 {
1208 #ifdef CONFIG_NEED_MULTIPLE_NODES
1209 	int start_rgn, end_rgn;
1210 	int i, ret;
1211 
1212 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
1213 	if (ret)
1214 		return ret;
1215 
1216 	for (i = start_rgn; i < end_rgn; i++)
1217 		memblock_set_region_node(&type->regions[i], nid);
1218 
1219 	memblock_merge_regions(type);
1220 #endif
1221 	return 0;
1222 }
1223 
1224 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
1225 /**
1226  * __next_mem_pfn_range_in_zone - iterator for for_each_*_range_in_zone()
1227  *
1228  * @idx: pointer to u64 loop variable
1229  * @zone: zone in which all of the memory blocks reside
1230  * @out_spfn: ptr to ulong for start pfn of the range, can be %NULL
1231  * @out_epfn: ptr to ulong for end pfn of the range, can be %NULL
1232  *
1233  * This function is meant to be a zone/pfn specific wrapper for the
1234  * for_each_mem_range type iterators. Specifically they are used in the
1235  * deferred memory init routines and as such we were duplicating much of
1236  * this logic throughout the code. So instead of having it in multiple
1237  * locations it seemed like it would make more sense to centralize this to
1238  * one new iterator that does everything they need.
1239  */
1240 void __init_memblock
1241 __next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone,
1242 			     unsigned long *out_spfn, unsigned long *out_epfn)
1243 {
1244 	int zone_nid = zone_to_nid(zone);
1245 	phys_addr_t spa, epa;
1246 	int nid;
1247 
1248 	__next_mem_range(idx, zone_nid, MEMBLOCK_NONE,
1249 			 &memblock.memory, &memblock.reserved,
1250 			 &spa, &epa, &nid);
1251 
1252 	while (*idx != U64_MAX) {
1253 		unsigned long epfn = PFN_DOWN(epa);
1254 		unsigned long spfn = PFN_UP(spa);
1255 
1256 		/*
1257 		 * Verify the end is at least past the start of the zone and
1258 		 * that we have at least one PFN to initialize.
1259 		 */
1260 		if (zone->zone_start_pfn < epfn && spfn < epfn) {
1261 			/* if we went too far just stop searching */
1262 			if (zone_end_pfn(zone) <= spfn) {
1263 				*idx = U64_MAX;
1264 				break;
1265 			}
1266 
1267 			if (out_spfn)
1268 				*out_spfn = max(zone->zone_start_pfn, spfn);
1269 			if (out_epfn)
1270 				*out_epfn = min(zone_end_pfn(zone), epfn);
1271 
1272 			return;
1273 		}
1274 
1275 		__next_mem_range(idx, zone_nid, MEMBLOCK_NONE,
1276 				 &memblock.memory, &memblock.reserved,
1277 				 &spa, &epa, &nid);
1278 	}
1279 
1280 	/* signal end of iteration */
1281 	if (out_spfn)
1282 		*out_spfn = ULONG_MAX;
1283 	if (out_epfn)
1284 		*out_epfn = 0;
1285 }
1286 
1287 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
1288 
1289 /**
1290  * memblock_alloc_range_nid - allocate boot memory block
1291  * @size: size of memory block to be allocated in bytes
1292  * @align: alignment of the region and block's size
1293  * @start: the lower bound of the memory region to allocate (phys address)
1294  * @end: the upper bound of the memory region to allocate (phys address)
1295  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1296  * @exact_nid: control the allocation fall back to other nodes
1297  *
1298  * The allocation is performed from memory region limited by
1299  * memblock.current_limit if @end == %MEMBLOCK_ALLOC_ACCESSIBLE.
1300  *
1301  * If the specified node can not hold the requested memory and @exact_nid
1302  * is false, the allocation falls back to any node in the system.
1303  *
1304  * For systems with memory mirroring, the allocation is attempted first
1305  * from the regions with mirroring enabled and then retried from any
1306  * memory region.
1307  *
1308  * In addition, function sets the min_count to 0 using kmemleak_alloc_phys for
1309  * allocated boot memory block, so that it is never reported as leaks.
1310  *
1311  * Return:
1312  * Physical address of allocated memory block on success, %0 on failure.
1313  */
1314 phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size,
1315 					phys_addr_t align, phys_addr_t start,
1316 					phys_addr_t end, int nid,
1317 					bool exact_nid)
1318 {
1319 	enum memblock_flags flags = choose_memblock_flags();
1320 	phys_addr_t found;
1321 
1322 	if (WARN_ONCE(nid == MAX_NUMNODES, "Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
1323 		nid = NUMA_NO_NODE;
1324 
1325 	if (!align) {
1326 		/* Can't use WARNs this early in boot on powerpc */
1327 		dump_stack();
1328 		align = SMP_CACHE_BYTES;
1329 	}
1330 
1331 again:
1332 	found = memblock_find_in_range_node(size, align, start, end, nid,
1333 					    flags);
1334 	if (found && !memblock_reserve(found, size))
1335 		goto done;
1336 
1337 	if (nid != NUMA_NO_NODE && !exact_nid) {
1338 		found = memblock_find_in_range_node(size, align, start,
1339 						    end, NUMA_NO_NODE,
1340 						    flags);
1341 		if (found && !memblock_reserve(found, size))
1342 			goto done;
1343 	}
1344 
1345 	if (flags & MEMBLOCK_MIRROR) {
1346 		flags &= ~MEMBLOCK_MIRROR;
1347 		pr_warn("Could not allocate %pap bytes of mirrored memory\n",
1348 			&size);
1349 		goto again;
1350 	}
1351 
1352 	return 0;
1353 
1354 done:
1355 	/* Skip kmemleak for kasan_init() due to high volume. */
1356 	if (end != MEMBLOCK_ALLOC_KASAN)
1357 		/*
1358 		 * The min_count is set to 0 so that memblock allocated
1359 		 * blocks are never reported as leaks. This is because many
1360 		 * of these blocks are only referred via the physical
1361 		 * address which is not looked up by kmemleak.
1362 		 */
1363 		kmemleak_alloc_phys(found, size, 0, 0);
1364 
1365 	return found;
1366 }
1367 
1368 /**
1369  * memblock_phys_alloc_range - allocate a memory block inside specified range
1370  * @size: size of memory block to be allocated in bytes
1371  * @align: alignment of the region and block's size
1372  * @start: the lower bound of the memory region to allocate (physical address)
1373  * @end: the upper bound of the memory region to allocate (physical address)
1374  *
1375  * Allocate @size bytes in the between @start and @end.
1376  *
1377  * Return: physical address of the allocated memory block on success,
1378  * %0 on failure.
1379  */
1380 phys_addr_t __init memblock_phys_alloc_range(phys_addr_t size,
1381 					     phys_addr_t align,
1382 					     phys_addr_t start,
1383 					     phys_addr_t end)
1384 {
1385 	memblock_dbg("%s: %llu bytes align=0x%llx from=%pa max_addr=%pa %pS\n",
1386 		     __func__, (u64)size, (u64)align, &start, &end,
1387 		     (void *)_RET_IP_);
1388 	return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE,
1389 					false);
1390 }
1391 
1392 /**
1393  * memblock_phys_alloc_try_nid - allocate a memory block from specified NUMA node
1394  * @size: size of memory block to be allocated in bytes
1395  * @align: alignment of the region and block's size
1396  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1397  *
1398  * Allocates memory block from the specified NUMA node. If the node
1399  * has no available memory, attempts to allocated from any node in the
1400  * system.
1401  *
1402  * Return: physical address of the allocated memory block on success,
1403  * %0 on failure.
1404  */
1405 phys_addr_t __init memblock_phys_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
1406 {
1407 	return memblock_alloc_range_nid(size, align, 0,
1408 					MEMBLOCK_ALLOC_ACCESSIBLE, nid, false);
1409 }
1410 
1411 /**
1412  * memblock_alloc_internal - allocate boot memory block
1413  * @size: size of memory block to be allocated in bytes
1414  * @align: alignment of the region and block's size
1415  * @min_addr: the lower bound of the memory region to allocate (phys address)
1416  * @max_addr: the upper bound of the memory region to allocate (phys address)
1417  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1418  * @exact_nid: control the allocation fall back to other nodes
1419  *
1420  * Allocates memory block using memblock_alloc_range_nid() and
1421  * converts the returned physical address to virtual.
1422  *
1423  * The @min_addr limit is dropped if it can not be satisfied and the allocation
1424  * will fall back to memory below @min_addr. Other constraints, such
1425  * as node and mirrored memory will be handled again in
1426  * memblock_alloc_range_nid().
1427  *
1428  * Return:
1429  * Virtual address of allocated memory block on success, NULL on failure.
1430  */
1431 static void * __init memblock_alloc_internal(
1432 				phys_addr_t size, phys_addr_t align,
1433 				phys_addr_t min_addr, phys_addr_t max_addr,
1434 				int nid, bool exact_nid)
1435 {
1436 	phys_addr_t alloc;
1437 
1438 	/*
1439 	 * Detect any accidental use of these APIs after slab is ready, as at
1440 	 * this moment memblock may be deinitialized already and its
1441 	 * internal data may be destroyed (after execution of memblock_free_all)
1442 	 */
1443 	if (WARN_ON_ONCE(slab_is_available()))
1444 		return kzalloc_node(size, GFP_NOWAIT, nid);
1445 
1446 	if (max_addr > memblock.current_limit)
1447 		max_addr = memblock.current_limit;
1448 
1449 	alloc = memblock_alloc_range_nid(size, align, min_addr, max_addr, nid,
1450 					exact_nid);
1451 
1452 	/* retry allocation without lower limit */
1453 	if (!alloc && min_addr)
1454 		alloc = memblock_alloc_range_nid(size, align, 0, max_addr, nid,
1455 						exact_nid);
1456 
1457 	if (!alloc)
1458 		return NULL;
1459 
1460 	return phys_to_virt(alloc);
1461 }
1462 
1463 /**
1464  * memblock_alloc_exact_nid_raw - allocate boot memory block on the exact node
1465  * without zeroing memory
1466  * @size: size of memory block to be allocated in bytes
1467  * @align: alignment of the region and block's size
1468  * @min_addr: the lower bound of the memory region from where the allocation
1469  *	  is preferred (phys address)
1470  * @max_addr: the upper bound of the memory region from where the allocation
1471  *	      is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to
1472  *	      allocate only from memory limited by memblock.current_limit value
1473  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1474  *
1475  * Public function, provides additional debug information (including caller
1476  * info), if enabled. Does not zero allocated memory.
1477  *
1478  * Return:
1479  * Virtual address of allocated memory block on success, NULL on failure.
1480  */
1481 void * __init memblock_alloc_exact_nid_raw(
1482 			phys_addr_t size, phys_addr_t align,
1483 			phys_addr_t min_addr, phys_addr_t max_addr,
1484 			int nid)
1485 {
1486 	void *ptr;
1487 
1488 	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
1489 		     __func__, (u64)size, (u64)align, nid, &min_addr,
1490 		     &max_addr, (void *)_RET_IP_);
1491 
1492 	ptr = memblock_alloc_internal(size, align,
1493 					   min_addr, max_addr, nid, true);
1494 	if (ptr && size > 0)
1495 		page_init_poison(ptr, size);
1496 
1497 	return ptr;
1498 }
1499 
1500 /**
1501  * memblock_alloc_try_nid_raw - allocate boot memory block without zeroing
1502  * memory and without panicking
1503  * @size: size of memory block to be allocated in bytes
1504  * @align: alignment of the region and block's size
1505  * @min_addr: the lower bound of the memory region from where the allocation
1506  *	  is preferred (phys address)
1507  * @max_addr: the upper bound of the memory region from where the allocation
1508  *	      is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to
1509  *	      allocate only from memory limited by memblock.current_limit value
1510  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1511  *
1512  * Public function, provides additional debug information (including caller
1513  * info), if enabled. Does not zero allocated memory, does not panic if request
1514  * cannot be satisfied.
1515  *
1516  * Return:
1517  * Virtual address of allocated memory block on success, NULL on failure.
1518  */
1519 void * __init memblock_alloc_try_nid_raw(
1520 			phys_addr_t size, phys_addr_t align,
1521 			phys_addr_t min_addr, phys_addr_t max_addr,
1522 			int nid)
1523 {
1524 	void *ptr;
1525 
1526 	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
1527 		     __func__, (u64)size, (u64)align, nid, &min_addr,
1528 		     &max_addr, (void *)_RET_IP_);
1529 
1530 	ptr = memblock_alloc_internal(size, align,
1531 					   min_addr, max_addr, nid, false);
1532 	if (ptr && size > 0)
1533 		page_init_poison(ptr, size);
1534 
1535 	return ptr;
1536 }
1537 
1538 /**
1539  * memblock_alloc_try_nid - allocate boot memory block
1540  * @size: size of memory block to be allocated in bytes
1541  * @align: alignment of the region and block's size
1542  * @min_addr: the lower bound of the memory region from where the allocation
1543  *	  is preferred (phys address)
1544  * @max_addr: the upper bound of the memory region from where the allocation
1545  *	      is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to
1546  *	      allocate only from memory limited by memblock.current_limit value
1547  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1548  *
1549  * Public function, provides additional debug information (including caller
1550  * info), if enabled. This function zeroes the allocated memory.
1551  *
1552  * Return:
1553  * Virtual address of allocated memory block on success, NULL on failure.
1554  */
1555 void * __init memblock_alloc_try_nid(
1556 			phys_addr_t size, phys_addr_t align,
1557 			phys_addr_t min_addr, phys_addr_t max_addr,
1558 			int nid)
1559 {
1560 	void *ptr;
1561 
1562 	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
1563 		     __func__, (u64)size, (u64)align, nid, &min_addr,
1564 		     &max_addr, (void *)_RET_IP_);
1565 	ptr = memblock_alloc_internal(size, align,
1566 					   min_addr, max_addr, nid, false);
1567 	if (ptr)
1568 		memset(ptr, 0, size);
1569 
1570 	return ptr;
1571 }
1572 
1573 /**
1574  * __memblock_free_late - free pages directly to buddy allocator
1575  * @base: phys starting address of the  boot memory block
1576  * @size: size of the boot memory block in bytes
1577  *
1578  * This is only useful when the memblock allocator has already been torn
1579  * down, but we are still initializing the system.  Pages are released directly
1580  * to the buddy allocator.
1581  */
1582 void __init __memblock_free_late(phys_addr_t base, phys_addr_t size)
1583 {
1584 	phys_addr_t cursor, end;
1585 
1586 	end = base + size - 1;
1587 	memblock_dbg("%s: [%pa-%pa] %pS\n",
1588 		     __func__, &base, &end, (void *)_RET_IP_);
1589 	kmemleak_free_part_phys(base, size);
1590 	cursor = PFN_UP(base);
1591 	end = PFN_DOWN(base + size);
1592 
1593 	for (; cursor < end; cursor++) {
1594 		memblock_free_pages(pfn_to_page(cursor), cursor, 0);
1595 		totalram_pages_inc();
1596 	}
1597 }
1598 
1599 /*
1600  * Remaining API functions
1601  */
1602 
1603 phys_addr_t __init_memblock memblock_phys_mem_size(void)
1604 {
1605 	return memblock.memory.total_size;
1606 }
1607 
1608 phys_addr_t __init_memblock memblock_reserved_size(void)
1609 {
1610 	return memblock.reserved.total_size;
1611 }
1612 
1613 /* lowest address */
1614 phys_addr_t __init_memblock memblock_start_of_DRAM(void)
1615 {
1616 	return memblock.memory.regions[0].base;
1617 }
1618 
1619 phys_addr_t __init_memblock memblock_end_of_DRAM(void)
1620 {
1621 	int idx = memblock.memory.cnt - 1;
1622 
1623 	return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
1624 }
1625 
1626 static phys_addr_t __init_memblock __find_max_addr(phys_addr_t limit)
1627 {
1628 	phys_addr_t max_addr = PHYS_ADDR_MAX;
1629 	struct memblock_region *r;
1630 
1631 	/*
1632 	 * translate the memory @limit size into the max address within one of
1633 	 * the memory memblock regions, if the @limit exceeds the total size
1634 	 * of those regions, max_addr will keep original value PHYS_ADDR_MAX
1635 	 */
1636 	for_each_mem_region(r) {
1637 		if (limit <= r->size) {
1638 			max_addr = r->base + limit;
1639 			break;
1640 		}
1641 		limit -= r->size;
1642 	}
1643 
1644 	return max_addr;
1645 }
1646 
1647 void __init memblock_enforce_memory_limit(phys_addr_t limit)
1648 {
1649 	phys_addr_t max_addr;
1650 
1651 	if (!limit)
1652 		return;
1653 
1654 	max_addr = __find_max_addr(limit);
1655 
1656 	/* @limit exceeds the total size of the memory, do nothing */
1657 	if (max_addr == PHYS_ADDR_MAX)
1658 		return;
1659 
1660 	/* truncate both memory and reserved regions */
1661 	memblock_remove_range(&memblock.memory, max_addr,
1662 			      PHYS_ADDR_MAX);
1663 	memblock_remove_range(&memblock.reserved, max_addr,
1664 			      PHYS_ADDR_MAX);
1665 }
1666 
1667 void __init memblock_cap_memory_range(phys_addr_t base, phys_addr_t size)
1668 {
1669 	int start_rgn, end_rgn;
1670 	int i, ret;
1671 
1672 	if (!size)
1673 		return;
1674 
1675 	ret = memblock_isolate_range(&memblock.memory, base, size,
1676 						&start_rgn, &end_rgn);
1677 	if (ret)
1678 		return;
1679 
1680 	/* remove all the MAP regions */
1681 	for (i = memblock.memory.cnt - 1; i >= end_rgn; i--)
1682 		if (!memblock_is_nomap(&memblock.memory.regions[i]))
1683 			memblock_remove_region(&memblock.memory, i);
1684 
1685 	for (i = start_rgn - 1; i >= 0; i--)
1686 		if (!memblock_is_nomap(&memblock.memory.regions[i]))
1687 			memblock_remove_region(&memblock.memory, i);
1688 
1689 	/* truncate the reserved regions */
1690 	memblock_remove_range(&memblock.reserved, 0, base);
1691 	memblock_remove_range(&memblock.reserved,
1692 			base + size, PHYS_ADDR_MAX);
1693 }
1694 
1695 void __init memblock_mem_limit_remove_map(phys_addr_t limit)
1696 {
1697 	phys_addr_t max_addr;
1698 
1699 	if (!limit)
1700 		return;
1701 
1702 	max_addr = __find_max_addr(limit);
1703 
1704 	/* @limit exceeds the total size of the memory, do nothing */
1705 	if (max_addr == PHYS_ADDR_MAX)
1706 		return;
1707 
1708 	memblock_cap_memory_range(0, max_addr);
1709 }
1710 
1711 static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
1712 {
1713 	unsigned int left = 0, right = type->cnt;
1714 
1715 	do {
1716 		unsigned int mid = (right + left) / 2;
1717 
1718 		if (addr < type->regions[mid].base)
1719 			right = mid;
1720 		else if (addr >= (type->regions[mid].base +
1721 				  type->regions[mid].size))
1722 			left = mid + 1;
1723 		else
1724 			return mid;
1725 	} while (left < right);
1726 	return -1;
1727 }
1728 
1729 bool __init_memblock memblock_is_reserved(phys_addr_t addr)
1730 {
1731 	return memblock_search(&memblock.reserved, addr) != -1;
1732 }
1733 
1734 bool __init_memblock memblock_is_memory(phys_addr_t addr)
1735 {
1736 	return memblock_search(&memblock.memory, addr) != -1;
1737 }
1738 
1739 bool __init_memblock memblock_is_map_memory(phys_addr_t addr)
1740 {
1741 	int i = memblock_search(&memblock.memory, addr);
1742 
1743 	if (i == -1)
1744 		return false;
1745 	return !memblock_is_nomap(&memblock.memory.regions[i]);
1746 }
1747 
1748 int __init_memblock memblock_search_pfn_nid(unsigned long pfn,
1749 			 unsigned long *start_pfn, unsigned long *end_pfn)
1750 {
1751 	struct memblock_type *type = &memblock.memory;
1752 	int mid = memblock_search(type, PFN_PHYS(pfn));
1753 
1754 	if (mid == -1)
1755 		return -1;
1756 
1757 	*start_pfn = PFN_DOWN(type->regions[mid].base);
1758 	*end_pfn = PFN_DOWN(type->regions[mid].base + type->regions[mid].size);
1759 
1760 	return memblock_get_region_node(&type->regions[mid]);
1761 }
1762 
1763 /**
1764  * memblock_is_region_memory - check if a region is a subset of memory
1765  * @base: base of region to check
1766  * @size: size of region to check
1767  *
1768  * Check if the region [@base, @base + @size) is a subset of a memory block.
1769  *
1770  * Return:
1771  * 0 if false, non-zero if true
1772  */
1773 bool __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
1774 {
1775 	int idx = memblock_search(&memblock.memory, base);
1776 	phys_addr_t end = base + memblock_cap_size(base, &size);
1777 
1778 	if (idx == -1)
1779 		return false;
1780 	return (memblock.memory.regions[idx].base +
1781 		 memblock.memory.regions[idx].size) >= end;
1782 }
1783 
1784 /**
1785  * memblock_is_region_reserved - check if a region intersects reserved memory
1786  * @base: base of region to check
1787  * @size: size of region to check
1788  *
1789  * Check if the region [@base, @base + @size) intersects a reserved
1790  * memory block.
1791  *
1792  * Return:
1793  * True if they intersect, false if not.
1794  */
1795 bool __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
1796 {
1797 	memblock_cap_size(base, &size);
1798 	return memblock_overlaps_region(&memblock.reserved, base, size);
1799 }
1800 
1801 void __init_memblock memblock_trim_memory(phys_addr_t align)
1802 {
1803 	phys_addr_t start, end, orig_start, orig_end;
1804 	struct memblock_region *r;
1805 
1806 	for_each_mem_region(r) {
1807 		orig_start = r->base;
1808 		orig_end = r->base + r->size;
1809 		start = round_up(orig_start, align);
1810 		end = round_down(orig_end, align);
1811 
1812 		if (start == orig_start && end == orig_end)
1813 			continue;
1814 
1815 		if (start < end) {
1816 			r->base = start;
1817 			r->size = end - start;
1818 		} else {
1819 			memblock_remove_region(&memblock.memory,
1820 					       r - memblock.memory.regions);
1821 			r--;
1822 		}
1823 	}
1824 }
1825 
1826 void __init_memblock memblock_set_current_limit(phys_addr_t limit)
1827 {
1828 	memblock.current_limit = limit;
1829 }
1830 
1831 phys_addr_t __init_memblock memblock_get_current_limit(void)
1832 {
1833 	return memblock.current_limit;
1834 }
1835 
1836 static void __init_memblock memblock_dump(struct memblock_type *type)
1837 {
1838 	phys_addr_t base, end, size;
1839 	enum memblock_flags flags;
1840 	int idx;
1841 	struct memblock_region *rgn;
1842 
1843 	pr_info(" %s.cnt  = 0x%lx\n", type->name, type->cnt);
1844 
1845 	for_each_memblock_type(idx, type, rgn) {
1846 		char nid_buf[32] = "";
1847 
1848 		base = rgn->base;
1849 		size = rgn->size;
1850 		end = base + size - 1;
1851 		flags = rgn->flags;
1852 #ifdef CONFIG_NEED_MULTIPLE_NODES
1853 		if (memblock_get_region_node(rgn) != MAX_NUMNODES)
1854 			snprintf(nid_buf, sizeof(nid_buf), " on node %d",
1855 				 memblock_get_region_node(rgn));
1856 #endif
1857 		pr_info(" %s[%#x]\t[%pa-%pa], %pa bytes%s flags: %#x\n",
1858 			type->name, idx, &base, &end, &size, nid_buf, flags);
1859 	}
1860 }
1861 
1862 static void __init_memblock __memblock_dump_all(void)
1863 {
1864 	pr_info("MEMBLOCK configuration:\n");
1865 	pr_info(" memory size = %pa reserved size = %pa\n",
1866 		&memblock.memory.total_size,
1867 		&memblock.reserved.total_size);
1868 
1869 	memblock_dump(&memblock.memory);
1870 	memblock_dump(&memblock.reserved);
1871 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
1872 	memblock_dump(&physmem);
1873 #endif
1874 }
1875 
1876 void __init_memblock memblock_dump_all(void)
1877 {
1878 	if (memblock_debug)
1879 		__memblock_dump_all();
1880 }
1881 
1882 void __init memblock_allow_resize(void)
1883 {
1884 	memblock_can_resize = 1;
1885 }
1886 
1887 static int __init early_memblock(char *p)
1888 {
1889 	if (p && strstr(p, "debug"))
1890 		memblock_debug = 1;
1891 	return 0;
1892 }
1893 early_param("memblock", early_memblock);
1894 
1895 static void __init free_memmap(unsigned long start_pfn, unsigned long end_pfn)
1896 {
1897 	struct page *start_pg, *end_pg;
1898 	phys_addr_t pg, pgend;
1899 
1900 	/*
1901 	 * Convert start_pfn/end_pfn to a struct page pointer.
1902 	 */
1903 	start_pg = pfn_to_page(start_pfn - 1) + 1;
1904 	end_pg = pfn_to_page(end_pfn - 1) + 1;
1905 
1906 	/*
1907 	 * Convert to physical addresses, and round start upwards and end
1908 	 * downwards.
1909 	 */
1910 	pg = PAGE_ALIGN(__pa(start_pg));
1911 	pgend = __pa(end_pg) & PAGE_MASK;
1912 
1913 	/*
1914 	 * If there are free pages between these, free the section of the
1915 	 * memmap array.
1916 	 */
1917 	if (pg < pgend)
1918 		memblock_free(pg, pgend - pg);
1919 }
1920 
1921 /*
1922  * The mem_map array can get very big.  Free the unused area of the memory map.
1923  */
1924 static void __init free_unused_memmap(void)
1925 {
1926 	unsigned long start, end, prev_end = 0;
1927 	int i;
1928 
1929 	if (!IS_ENABLED(CONFIG_HAVE_ARCH_PFN_VALID) ||
1930 	    IS_ENABLED(CONFIG_SPARSEMEM_VMEMMAP))
1931 		return;
1932 
1933 	/*
1934 	 * This relies on each bank being in address order.
1935 	 * The banks are sorted previously in bootmem_init().
1936 	 */
1937 	for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, NULL) {
1938 #ifdef CONFIG_SPARSEMEM
1939 		/*
1940 		 * Take care not to free memmap entries that don't exist
1941 		 * due to SPARSEMEM sections which aren't present.
1942 		 */
1943 		start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
1944 #else
1945 		/*
1946 		 * Align down here since the VM subsystem insists that the
1947 		 * memmap entries are valid from the bank start aligned to
1948 		 * MAX_ORDER_NR_PAGES.
1949 		 */
1950 		start = round_down(start, MAX_ORDER_NR_PAGES);
1951 #endif
1952 
1953 		/*
1954 		 * If we had a previous bank, and there is a space
1955 		 * between the current bank and the previous, free it.
1956 		 */
1957 		if (prev_end && prev_end < start)
1958 			free_memmap(prev_end, start);
1959 
1960 		/*
1961 		 * Align up here since the VM subsystem insists that the
1962 		 * memmap entries are valid from the bank end aligned to
1963 		 * MAX_ORDER_NR_PAGES.
1964 		 */
1965 		prev_end = ALIGN(end, MAX_ORDER_NR_PAGES);
1966 	}
1967 
1968 #ifdef CONFIG_SPARSEMEM
1969 	if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
1970 		free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
1971 #endif
1972 }
1973 
1974 static void __init __free_pages_memory(unsigned long start, unsigned long end)
1975 {
1976 	int order;
1977 
1978 	while (start < end) {
1979 		order = min(MAX_ORDER - 1UL, __ffs(start));
1980 
1981 		while (start + (1UL << order) > end)
1982 			order--;
1983 
1984 		memblock_free_pages(pfn_to_page(start), start, order);
1985 
1986 		start += (1UL << order);
1987 	}
1988 }
1989 
1990 static unsigned long __init __free_memory_core(phys_addr_t start,
1991 				 phys_addr_t end)
1992 {
1993 	unsigned long start_pfn = PFN_UP(start);
1994 	unsigned long end_pfn = min_t(unsigned long,
1995 				      PFN_DOWN(end), max_low_pfn);
1996 
1997 	if (start_pfn >= end_pfn)
1998 		return 0;
1999 
2000 	__free_pages_memory(start_pfn, end_pfn);
2001 
2002 	return end_pfn - start_pfn;
2003 }
2004 
2005 static unsigned long __init free_low_memory_core_early(void)
2006 {
2007 	unsigned long count = 0;
2008 	phys_addr_t start, end;
2009 	u64 i;
2010 
2011 	memblock_clear_hotplug(0, -1);
2012 
2013 	for_each_reserved_mem_range(i, &start, &end)
2014 		reserve_bootmem_region(start, end);
2015 
2016 	/*
2017 	 * We need to use NUMA_NO_NODE instead of NODE_DATA(0)->node_id
2018 	 *  because in some case like Node0 doesn't have RAM installed
2019 	 *  low ram will be on Node1
2020 	 */
2021 	for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE, &start, &end,
2022 				NULL)
2023 		count += __free_memory_core(start, end);
2024 
2025 	return count;
2026 }
2027 
2028 static int reset_managed_pages_done __initdata;
2029 
2030 void reset_node_managed_pages(pg_data_t *pgdat)
2031 {
2032 	struct zone *z;
2033 
2034 	for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
2035 		atomic_long_set(&z->managed_pages, 0);
2036 }
2037 
2038 void __init reset_all_zones_managed_pages(void)
2039 {
2040 	struct pglist_data *pgdat;
2041 
2042 	if (reset_managed_pages_done)
2043 		return;
2044 
2045 	for_each_online_pgdat(pgdat)
2046 		reset_node_managed_pages(pgdat);
2047 
2048 	reset_managed_pages_done = 1;
2049 }
2050 
2051 /**
2052  * memblock_free_all - release free pages to the buddy allocator
2053  */
2054 void __init memblock_free_all(void)
2055 {
2056 	unsigned long pages;
2057 
2058 	free_unused_memmap();
2059 	reset_all_zones_managed_pages();
2060 
2061 	pages = free_low_memory_core_early();
2062 	totalram_pages_add(pages);
2063 }
2064 
2065 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_ARCH_KEEP_MEMBLOCK)
2066 
2067 static int memblock_debug_show(struct seq_file *m, void *private)
2068 {
2069 	struct memblock_type *type = m->private;
2070 	struct memblock_region *reg;
2071 	int i;
2072 	phys_addr_t end;
2073 
2074 	for (i = 0; i < type->cnt; i++) {
2075 		reg = &type->regions[i];
2076 		end = reg->base + reg->size - 1;
2077 
2078 		seq_printf(m, "%4d: ", i);
2079 		seq_printf(m, "%pa..%pa\n", &reg->base, &end);
2080 	}
2081 	return 0;
2082 }
2083 DEFINE_SHOW_ATTRIBUTE(memblock_debug);
2084 
2085 static int __init memblock_init_debugfs(void)
2086 {
2087 	struct dentry *root = debugfs_create_dir("memblock", NULL);
2088 
2089 	debugfs_create_file("memory", 0444, root,
2090 			    &memblock.memory, &memblock_debug_fops);
2091 	debugfs_create_file("reserved", 0444, root,
2092 			    &memblock.reserved, &memblock_debug_fops);
2093 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
2094 	debugfs_create_file("physmem", 0444, root, &physmem,
2095 			    &memblock_debug_fops);
2096 #endif
2097 
2098 	return 0;
2099 }
2100 __initcall(memblock_init_debugfs);
2101 
2102 #endif /* CONFIG_DEBUG_FS */
2103