xref: /openbmc/linux/mm/memblock.c (revision b8d312aa)
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  * * ``physmap`` - describes the actual physical memory regardless of
48  *   the possible restrictions; the ``physmap`` type is only available
49  *   on some architectures.
50  *
51  * Each region is represented by :c:type:`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 :c:type:`struct
54  * memblock_type` which contains an array of memory regions along with
55  * the allocator metadata. The memory types are nicely wrapped with
56  * :c:type:`struct memblock`. This structure is statically initialzed
57  * at build time. The region arrays for the "memory" and "reserved"
58  * types are initially sized to %INIT_MEMBLOCK_REGIONS and for the
59  * "physmap" type to %INIT_PHYSMEM_REGIONS.
60  * The :c:func:`memblock_allow_resize` enables automatic resizing of
61  * the region arrays during addition of new regions. This feature
62  * should be used with care so that memory allocated for the region
63  * array will not overlap with areas that should be reserved, for
64  * example initrd.
65  *
66  * The early architecture setup should tell memblock what the physical
67  * memory layout is by using :c:func:`memblock_add` or
68  * :c:func:`memblock_add_node` functions. The first function does not
69  * assign the region to a NUMA node and it is appropriate for UMA
70  * systems. Yet, it is possible to use it on NUMA systems as well and
71  * assign the region to a NUMA node later in the setup process using
72  * :c:func:`memblock_set_node`. The :c:func:`memblock_add_node`
73  * performs such an assignment directly.
74  *
75  * Once memblock is setup the memory can be allocated using one of the
76  * API variants:
77  *
78  * * :c:func:`memblock_phys_alloc*` - these functions return the
79  *   **physical** address of the allocated memory
80  * * :c:func:`memblock_alloc*` - these functions return the **virtual**
81  *   address of the allocated memory.
82  *
83  * Note, that both API variants use implict assumptions about allowed
84  * memory ranges and the fallback methods. Consult the documentation
85  * of :c:func:`memblock_alloc_internal` and
86  * :c:func:`memblock_alloc_range_nid` functions for more elaboarte
87  * description.
88  *
89  * As the system boot progresses, the architecture specific
90  * :c:func:`mem_init` function frees all the memory to the buddy page
91  * allocator.
92  *
93  * Unless an architecure enables %CONFIG_ARCH_KEEP_MEMBLOCK, the
94  * memblock data structures will be discarded after the system
95  * initialization compltes.
96  */
97 
98 #ifndef CONFIG_NEED_MULTIPLE_NODES
99 struct pglist_data __refdata contig_page_data;
100 EXPORT_SYMBOL(contig_page_data);
101 #endif
102 
103 unsigned long max_low_pfn;
104 unsigned long min_low_pfn;
105 unsigned long max_pfn;
106 unsigned long long max_possible_pfn;
107 
108 static struct memblock_region memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS] __initdata_memblock;
109 static struct memblock_region memblock_reserved_init_regions[INIT_MEMBLOCK_RESERVED_REGIONS] __initdata_memblock;
110 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
111 static struct memblock_region memblock_physmem_init_regions[INIT_PHYSMEM_REGIONS] __initdata_memblock;
112 #endif
113 
114 struct memblock memblock __initdata_memblock = {
115 	.memory.regions		= memblock_memory_init_regions,
116 	.memory.cnt		= 1,	/* empty dummy entry */
117 	.memory.max		= INIT_MEMBLOCK_REGIONS,
118 	.memory.name		= "memory",
119 
120 	.reserved.regions	= memblock_reserved_init_regions,
121 	.reserved.cnt		= 1,	/* empty dummy entry */
122 	.reserved.max		= INIT_MEMBLOCK_RESERVED_REGIONS,
123 	.reserved.name		= "reserved",
124 
125 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
126 	.physmem.regions	= memblock_physmem_init_regions,
127 	.physmem.cnt		= 1,	/* empty dummy entry */
128 	.physmem.max		= INIT_PHYSMEM_REGIONS,
129 	.physmem.name		= "physmem",
130 #endif
131 
132 	.bottom_up		= false,
133 	.current_limit		= MEMBLOCK_ALLOC_ANYWHERE,
134 };
135 
136 int memblock_debug __initdata_memblock;
137 static bool system_has_some_mirror __initdata_memblock = false;
138 static int memblock_can_resize __initdata_memblock;
139 static int memblock_memory_in_slab __initdata_memblock = 0;
140 static int memblock_reserved_in_slab __initdata_memblock = 0;
141 
142 static enum memblock_flags __init_memblock choose_memblock_flags(void)
143 {
144 	return system_has_some_mirror ? MEMBLOCK_MIRROR : MEMBLOCK_NONE;
145 }
146 
147 /* adjust *@size so that (@base + *@size) doesn't overflow, return new size */
148 static inline phys_addr_t memblock_cap_size(phys_addr_t base, phys_addr_t *size)
149 {
150 	return *size = min(*size, PHYS_ADDR_MAX - base);
151 }
152 
153 /*
154  * Address comparison utilities
155  */
156 static unsigned long __init_memblock memblock_addrs_overlap(phys_addr_t base1, phys_addr_t size1,
157 				       phys_addr_t base2, phys_addr_t size2)
158 {
159 	return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
160 }
161 
162 bool __init_memblock memblock_overlaps_region(struct memblock_type *type,
163 					phys_addr_t base, phys_addr_t size)
164 {
165 	unsigned long i;
166 
167 	for (i = 0; i < type->cnt; i++)
168 		if (memblock_addrs_overlap(base, size, type->regions[i].base,
169 					   type->regions[i].size))
170 			break;
171 	return i < type->cnt;
172 }
173 
174 /**
175  * __memblock_find_range_bottom_up - find free area utility in bottom-up
176  * @start: start of candidate range
177  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
178  *       %MEMBLOCK_ALLOC_ACCESSIBLE
179  * @size: size of free area to find
180  * @align: alignment of free area to find
181  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
182  * @flags: pick from blocks based on memory attributes
183  *
184  * Utility called from memblock_find_in_range_node(), find free area bottom-up.
185  *
186  * Return:
187  * Found address on success, 0 on failure.
188  */
189 static phys_addr_t __init_memblock
190 __memblock_find_range_bottom_up(phys_addr_t start, phys_addr_t end,
191 				phys_addr_t size, phys_addr_t align, int nid,
192 				enum memblock_flags flags)
193 {
194 	phys_addr_t this_start, this_end, cand;
195 	u64 i;
196 
197 	for_each_free_mem_range(i, nid, flags, &this_start, &this_end, NULL) {
198 		this_start = clamp(this_start, start, end);
199 		this_end = clamp(this_end, start, end);
200 
201 		cand = round_up(this_start, align);
202 		if (cand < this_end && this_end - cand >= size)
203 			return cand;
204 	}
205 
206 	return 0;
207 }
208 
209 /**
210  * __memblock_find_range_top_down - find free area utility, in top-down
211  * @start: start of candidate range
212  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
213  *       %MEMBLOCK_ALLOC_ACCESSIBLE
214  * @size: size of free area to find
215  * @align: alignment of free area to find
216  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
217  * @flags: pick from blocks based on memory attributes
218  *
219  * Utility called from memblock_find_in_range_node(), find free area top-down.
220  *
221  * Return:
222  * Found address on success, 0 on failure.
223  */
224 static phys_addr_t __init_memblock
225 __memblock_find_range_top_down(phys_addr_t start, phys_addr_t end,
226 			       phys_addr_t size, phys_addr_t align, int nid,
227 			       enum memblock_flags flags)
228 {
229 	phys_addr_t this_start, this_end, cand;
230 	u64 i;
231 
232 	for_each_free_mem_range_reverse(i, nid, flags, &this_start, &this_end,
233 					NULL) {
234 		this_start = clamp(this_start, start, end);
235 		this_end = clamp(this_end, start, end);
236 
237 		if (this_end < size)
238 			continue;
239 
240 		cand = round_down(this_end - size, align);
241 		if (cand >= this_start)
242 			return cand;
243 	}
244 
245 	return 0;
246 }
247 
248 /**
249  * memblock_find_in_range_node - find free area in given range and node
250  * @size: size of free area to find
251  * @align: alignment of free area to find
252  * @start: start of candidate range
253  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
254  *       %MEMBLOCK_ALLOC_ACCESSIBLE
255  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
256  * @flags: pick from blocks based on memory attributes
257  *
258  * Find @size free area aligned to @align in the specified range and node.
259  *
260  * When allocation direction is bottom-up, the @start should be greater
261  * than the end of the kernel image. Otherwise, it will be trimmed. The
262  * reason is that we want the bottom-up allocation just near the kernel
263  * image so it is highly likely that the allocated memory and the kernel
264  * will reside in the same node.
265  *
266  * If bottom-up allocation failed, will try to allocate memory top-down.
267  *
268  * Return:
269  * Found address on success, 0 on failure.
270  */
271 static phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t size,
272 					phys_addr_t align, phys_addr_t start,
273 					phys_addr_t end, int nid,
274 					enum memblock_flags flags)
275 {
276 	phys_addr_t kernel_end, ret;
277 
278 	/* pump up @end */
279 	if (end == MEMBLOCK_ALLOC_ACCESSIBLE ||
280 	    end == MEMBLOCK_ALLOC_KASAN)
281 		end = memblock.current_limit;
282 
283 	/* avoid allocating the first page */
284 	start = max_t(phys_addr_t, start, PAGE_SIZE);
285 	end = max(start, end);
286 	kernel_end = __pa_symbol(_end);
287 
288 	/*
289 	 * try bottom-up allocation only when bottom-up mode
290 	 * is set and @end is above the kernel image.
291 	 */
292 	if (memblock_bottom_up() && end > kernel_end) {
293 		phys_addr_t bottom_up_start;
294 
295 		/* make sure we will allocate above the kernel */
296 		bottom_up_start = max(start, kernel_end);
297 
298 		/* ok, try bottom-up allocation first */
299 		ret = __memblock_find_range_bottom_up(bottom_up_start, end,
300 						      size, align, nid, flags);
301 		if (ret)
302 			return ret;
303 
304 		/*
305 		 * we always limit bottom-up allocation above the kernel,
306 		 * but top-down allocation doesn't have the limit, so
307 		 * retrying top-down allocation may succeed when bottom-up
308 		 * allocation failed.
309 		 *
310 		 * bottom-up allocation is expected to be fail very rarely,
311 		 * so we use WARN_ONCE() here to see the stack trace if
312 		 * fail happens.
313 		 */
314 		WARN_ONCE(IS_ENABLED(CONFIG_MEMORY_HOTREMOVE),
315 			  "memblock: bottom-up allocation failed, memory hotremove may be affected\n");
316 	}
317 
318 	return __memblock_find_range_top_down(start, end, size, align, nid,
319 					      flags);
320 }
321 
322 /**
323  * memblock_find_in_range - find free area in given range
324  * @start: start of candidate range
325  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
326  *       %MEMBLOCK_ALLOC_ACCESSIBLE
327  * @size: size of free area to find
328  * @align: alignment of free area to find
329  *
330  * Find @size free area aligned to @align in the specified range.
331  *
332  * Return:
333  * Found address on success, 0 on failure.
334  */
335 phys_addr_t __init_memblock memblock_find_in_range(phys_addr_t start,
336 					phys_addr_t end, phys_addr_t size,
337 					phys_addr_t align)
338 {
339 	phys_addr_t ret;
340 	enum memblock_flags flags = choose_memblock_flags();
341 
342 again:
343 	ret = memblock_find_in_range_node(size, align, start, end,
344 					    NUMA_NO_NODE, flags);
345 
346 	if (!ret && (flags & MEMBLOCK_MIRROR)) {
347 		pr_warn("Could not allocate %pap bytes of mirrored memory\n",
348 			&size);
349 		flags &= ~MEMBLOCK_MIRROR;
350 		goto again;
351 	}
352 
353 	return ret;
354 }
355 
356 static void __init_memblock memblock_remove_region(struct memblock_type *type, unsigned long r)
357 {
358 	type->total_size -= type->regions[r].size;
359 	memmove(&type->regions[r], &type->regions[r + 1],
360 		(type->cnt - (r + 1)) * sizeof(type->regions[r]));
361 	type->cnt--;
362 
363 	/* Special case for empty arrays */
364 	if (type->cnt == 0) {
365 		WARN_ON(type->total_size != 0);
366 		type->cnt = 1;
367 		type->regions[0].base = 0;
368 		type->regions[0].size = 0;
369 		type->regions[0].flags = 0;
370 		memblock_set_region_node(&type->regions[0], MAX_NUMNODES);
371 	}
372 }
373 
374 #ifndef CONFIG_ARCH_KEEP_MEMBLOCK
375 /**
376  * memblock_discard - discard memory and reserved arrays if they were allocated
377  */
378 void __init memblock_discard(void)
379 {
380 	phys_addr_t addr, size;
381 
382 	if (memblock.reserved.regions != memblock_reserved_init_regions) {
383 		addr = __pa(memblock.reserved.regions);
384 		size = PAGE_ALIGN(sizeof(struct memblock_region) *
385 				  memblock.reserved.max);
386 		__memblock_free_late(addr, size);
387 	}
388 
389 	if (memblock.memory.regions != memblock_memory_init_regions) {
390 		addr = __pa(memblock.memory.regions);
391 		size = PAGE_ALIGN(sizeof(struct memblock_region) *
392 				  memblock.memory.max);
393 		__memblock_free_late(addr, size);
394 	}
395 }
396 #endif
397 
398 /**
399  * memblock_double_array - double the size of the memblock regions array
400  * @type: memblock type of the regions array being doubled
401  * @new_area_start: starting address of memory range to avoid overlap with
402  * @new_area_size: size of memory range to avoid overlap with
403  *
404  * Double the size of the @type regions array. If memblock is being used to
405  * allocate memory for a new reserved regions array and there is a previously
406  * allocated memory range [@new_area_start, @new_area_start + @new_area_size]
407  * waiting to be reserved, ensure the memory used by the new array does
408  * not overlap.
409  *
410  * Return:
411  * 0 on success, -1 on failure.
412  */
413 static int __init_memblock memblock_double_array(struct memblock_type *type,
414 						phys_addr_t new_area_start,
415 						phys_addr_t new_area_size)
416 {
417 	struct memblock_region *new_array, *old_array;
418 	phys_addr_t old_alloc_size, new_alloc_size;
419 	phys_addr_t old_size, new_size, addr, new_end;
420 	int use_slab = slab_is_available();
421 	int *in_slab;
422 
423 	/* We don't allow resizing until we know about the reserved regions
424 	 * of memory that aren't suitable for allocation
425 	 */
426 	if (!memblock_can_resize)
427 		return -1;
428 
429 	/* Calculate new doubled size */
430 	old_size = type->max * sizeof(struct memblock_region);
431 	new_size = old_size << 1;
432 	/*
433 	 * We need to allocated new one align to PAGE_SIZE,
434 	 *   so we can free them completely later.
435 	 */
436 	old_alloc_size = PAGE_ALIGN(old_size);
437 	new_alloc_size = PAGE_ALIGN(new_size);
438 
439 	/* Retrieve the slab flag */
440 	if (type == &memblock.memory)
441 		in_slab = &memblock_memory_in_slab;
442 	else
443 		in_slab = &memblock_reserved_in_slab;
444 
445 	/* Try to find some space for it */
446 	if (use_slab) {
447 		new_array = kmalloc(new_size, GFP_KERNEL);
448 		addr = new_array ? __pa(new_array) : 0;
449 	} else {
450 		/* only exclude range when trying to double reserved.regions */
451 		if (type != &memblock.reserved)
452 			new_area_start = new_area_size = 0;
453 
454 		addr = memblock_find_in_range(new_area_start + new_area_size,
455 						memblock.current_limit,
456 						new_alloc_size, PAGE_SIZE);
457 		if (!addr && new_area_size)
458 			addr = memblock_find_in_range(0,
459 				min(new_area_start, memblock.current_limit),
460 				new_alloc_size, PAGE_SIZE);
461 
462 		new_array = addr ? __va(addr) : NULL;
463 	}
464 	if (!addr) {
465 		pr_err("memblock: Failed to double %s array from %ld to %ld entries !\n",
466 		       type->name, type->max, type->max * 2);
467 		return -1;
468 	}
469 
470 	new_end = addr + new_size - 1;
471 	memblock_dbg("memblock: %s is doubled to %ld at [%pa-%pa]",
472 			type->name, type->max * 2, &addr, &new_end);
473 
474 	/*
475 	 * Found space, we now need to move the array over before we add the
476 	 * reserved region since it may be our reserved array itself that is
477 	 * full.
478 	 */
479 	memcpy(new_array, type->regions, old_size);
480 	memset(new_array + type->max, 0, old_size);
481 	old_array = type->regions;
482 	type->regions = new_array;
483 	type->max <<= 1;
484 
485 	/* Free old array. We needn't free it if the array is the static one */
486 	if (*in_slab)
487 		kfree(old_array);
488 	else if (old_array != memblock_memory_init_regions &&
489 		 old_array != memblock_reserved_init_regions)
490 		memblock_free(__pa(old_array), old_alloc_size);
491 
492 	/*
493 	 * Reserve the new array if that comes from the memblock.  Otherwise, we
494 	 * needn't do it
495 	 */
496 	if (!use_slab)
497 		BUG_ON(memblock_reserve(addr, new_alloc_size));
498 
499 	/* Update slab flag */
500 	*in_slab = use_slab;
501 
502 	return 0;
503 }
504 
505 /**
506  * memblock_merge_regions - merge neighboring compatible regions
507  * @type: memblock type to scan
508  *
509  * Scan @type and merge neighboring compatible regions.
510  */
511 static void __init_memblock memblock_merge_regions(struct memblock_type *type)
512 {
513 	int i = 0;
514 
515 	/* cnt never goes below 1 */
516 	while (i < type->cnt - 1) {
517 		struct memblock_region *this = &type->regions[i];
518 		struct memblock_region *next = &type->regions[i + 1];
519 
520 		if (this->base + this->size != next->base ||
521 		    memblock_get_region_node(this) !=
522 		    memblock_get_region_node(next) ||
523 		    this->flags != next->flags) {
524 			BUG_ON(this->base + this->size > next->base);
525 			i++;
526 			continue;
527 		}
528 
529 		this->size += next->size;
530 		/* move forward from next + 1, index of which is i + 2 */
531 		memmove(next, next + 1, (type->cnt - (i + 2)) * sizeof(*next));
532 		type->cnt--;
533 	}
534 }
535 
536 /**
537  * memblock_insert_region - insert new memblock region
538  * @type:	memblock type to insert into
539  * @idx:	index for the insertion point
540  * @base:	base address of the new region
541  * @size:	size of the new region
542  * @nid:	node id of the new region
543  * @flags:	flags of the new region
544  *
545  * Insert new memblock region [@base, @base + @size) into @type at @idx.
546  * @type must already have extra room to accommodate the new region.
547  */
548 static void __init_memblock memblock_insert_region(struct memblock_type *type,
549 						   int idx, phys_addr_t base,
550 						   phys_addr_t size,
551 						   int nid,
552 						   enum memblock_flags flags)
553 {
554 	struct memblock_region *rgn = &type->regions[idx];
555 
556 	BUG_ON(type->cnt >= type->max);
557 	memmove(rgn + 1, rgn, (type->cnt - idx) * sizeof(*rgn));
558 	rgn->base = base;
559 	rgn->size = size;
560 	rgn->flags = flags;
561 	memblock_set_region_node(rgn, nid);
562 	type->cnt++;
563 	type->total_size += size;
564 }
565 
566 /**
567  * memblock_add_range - add new memblock region
568  * @type: memblock type to add new region into
569  * @base: base address of the new region
570  * @size: size of the new region
571  * @nid: nid of the new region
572  * @flags: flags of the new region
573  *
574  * Add new memblock region [@base, @base + @size) into @type.  The new region
575  * is allowed to overlap with existing ones - overlaps don't affect already
576  * existing regions.  @type is guaranteed to be minimal (all neighbouring
577  * compatible regions are merged) after the addition.
578  *
579  * Return:
580  * 0 on success, -errno on failure.
581  */
582 int __init_memblock memblock_add_range(struct memblock_type *type,
583 				phys_addr_t base, phys_addr_t size,
584 				int nid, enum memblock_flags flags)
585 {
586 	bool insert = false;
587 	phys_addr_t obase = base;
588 	phys_addr_t end = base + memblock_cap_size(base, &size);
589 	int idx, nr_new;
590 	struct memblock_region *rgn;
591 
592 	if (!size)
593 		return 0;
594 
595 	/* special case for empty array */
596 	if (type->regions[0].size == 0) {
597 		WARN_ON(type->cnt != 1 || type->total_size);
598 		type->regions[0].base = base;
599 		type->regions[0].size = size;
600 		type->regions[0].flags = flags;
601 		memblock_set_region_node(&type->regions[0], nid);
602 		type->total_size = size;
603 		return 0;
604 	}
605 repeat:
606 	/*
607 	 * The following is executed twice.  Once with %false @insert and
608 	 * then with %true.  The first counts the number of regions needed
609 	 * to accommodate the new area.  The second actually inserts them.
610 	 */
611 	base = obase;
612 	nr_new = 0;
613 
614 	for_each_memblock_type(idx, type, rgn) {
615 		phys_addr_t rbase = rgn->base;
616 		phys_addr_t rend = rbase + rgn->size;
617 
618 		if (rbase >= end)
619 			break;
620 		if (rend <= base)
621 			continue;
622 		/*
623 		 * @rgn overlaps.  If it separates the lower part of new
624 		 * area, insert that portion.
625 		 */
626 		if (rbase > base) {
627 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
628 			WARN_ON(nid != memblock_get_region_node(rgn));
629 #endif
630 			WARN_ON(flags != rgn->flags);
631 			nr_new++;
632 			if (insert)
633 				memblock_insert_region(type, idx++, base,
634 						       rbase - base, nid,
635 						       flags);
636 		}
637 		/* area below @rend is dealt with, forget about it */
638 		base = min(rend, end);
639 	}
640 
641 	/* insert the remaining portion */
642 	if (base < end) {
643 		nr_new++;
644 		if (insert)
645 			memblock_insert_region(type, idx, base, end - base,
646 					       nid, flags);
647 	}
648 
649 	if (!nr_new)
650 		return 0;
651 
652 	/*
653 	 * If this was the first round, resize array and repeat for actual
654 	 * insertions; otherwise, merge and return.
655 	 */
656 	if (!insert) {
657 		while (type->cnt + nr_new > type->max)
658 			if (memblock_double_array(type, obase, size) < 0)
659 				return -ENOMEM;
660 		insert = true;
661 		goto repeat;
662 	} else {
663 		memblock_merge_regions(type);
664 		return 0;
665 	}
666 }
667 
668 /**
669  * memblock_add_node - add new memblock region within a NUMA node
670  * @base: base address of the new region
671  * @size: size of the new region
672  * @nid: nid 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_node(phys_addr_t base, phys_addr_t size,
681 				       int nid)
682 {
683 	return memblock_add_range(&memblock.memory, base, size, nid, 0);
684 }
685 
686 /**
687  * memblock_add - add new memblock region
688  * @base: base address of the new region
689  * @size: size of the new region
690  *
691  * Add new memblock region [@base, @base + @size) to the "memory"
692  * type. See memblock_add_range() description for mode details
693  *
694  * Return:
695  * 0 on success, -errno on failure.
696  */
697 int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
698 {
699 	phys_addr_t end = base + size - 1;
700 
701 	memblock_dbg("memblock_add: [%pa-%pa] %pS\n",
702 		     &base, &end, (void *)_RET_IP_);
703 
704 	return memblock_add_range(&memblock.memory, base, size, MAX_NUMNODES, 0);
705 }
706 
707 /**
708  * memblock_isolate_range - isolate given range into disjoint memblocks
709  * @type: memblock type to isolate range for
710  * @base: base of range to isolate
711  * @size: size of range to isolate
712  * @start_rgn: out parameter for the start of isolated region
713  * @end_rgn: out parameter for the end of isolated region
714  *
715  * Walk @type and ensure that regions don't cross the boundaries defined by
716  * [@base, @base + @size).  Crossing regions are split at the boundaries,
717  * which may create at most two more regions.  The index of the first
718  * region inside the range is returned in *@start_rgn and end in *@end_rgn.
719  *
720  * Return:
721  * 0 on success, -errno on failure.
722  */
723 static int __init_memblock memblock_isolate_range(struct memblock_type *type,
724 					phys_addr_t base, phys_addr_t size,
725 					int *start_rgn, int *end_rgn)
726 {
727 	phys_addr_t end = base + memblock_cap_size(base, &size);
728 	int idx;
729 	struct memblock_region *rgn;
730 
731 	*start_rgn = *end_rgn = 0;
732 
733 	if (!size)
734 		return 0;
735 
736 	/* we'll create at most two more regions */
737 	while (type->cnt + 2 > type->max)
738 		if (memblock_double_array(type, base, size) < 0)
739 			return -ENOMEM;
740 
741 	for_each_memblock_type(idx, type, rgn) {
742 		phys_addr_t rbase = rgn->base;
743 		phys_addr_t rend = rbase + rgn->size;
744 
745 		if (rbase >= end)
746 			break;
747 		if (rend <= base)
748 			continue;
749 
750 		if (rbase < base) {
751 			/*
752 			 * @rgn intersects from below.  Split and continue
753 			 * to process the next region - the new top half.
754 			 */
755 			rgn->base = base;
756 			rgn->size -= base - rbase;
757 			type->total_size -= base - rbase;
758 			memblock_insert_region(type, idx, rbase, base - rbase,
759 					       memblock_get_region_node(rgn),
760 					       rgn->flags);
761 		} else if (rend > end) {
762 			/*
763 			 * @rgn intersects from above.  Split and redo the
764 			 * current region - the new bottom half.
765 			 */
766 			rgn->base = end;
767 			rgn->size -= end - rbase;
768 			type->total_size -= end - rbase;
769 			memblock_insert_region(type, idx--, rbase, end - rbase,
770 					       memblock_get_region_node(rgn),
771 					       rgn->flags);
772 		} else {
773 			/* @rgn is fully contained, record it */
774 			if (!*end_rgn)
775 				*start_rgn = idx;
776 			*end_rgn = idx + 1;
777 		}
778 	}
779 
780 	return 0;
781 }
782 
783 static int __init_memblock memblock_remove_range(struct memblock_type *type,
784 					  phys_addr_t base, phys_addr_t size)
785 {
786 	int start_rgn, end_rgn;
787 	int i, ret;
788 
789 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
790 	if (ret)
791 		return ret;
792 
793 	for (i = end_rgn - 1; i >= start_rgn; i--)
794 		memblock_remove_region(type, i);
795 	return 0;
796 }
797 
798 int __init_memblock memblock_remove(phys_addr_t base, phys_addr_t size)
799 {
800 	phys_addr_t end = base + size - 1;
801 
802 	memblock_dbg("memblock_remove: [%pa-%pa] %pS\n",
803 		     &base, &end, (void *)_RET_IP_);
804 
805 	return memblock_remove_range(&memblock.memory, base, size);
806 }
807 
808 /**
809  * memblock_free - free boot memory block
810  * @base: phys starting address of the  boot memory block
811  * @size: size of the boot memory block in bytes
812  *
813  * Free boot memory block previously allocated by memblock_alloc_xx() API.
814  * The freeing memory will not be released to the buddy allocator.
815  */
816 int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)
817 {
818 	phys_addr_t end = base + size - 1;
819 
820 	memblock_dbg("   memblock_free: [%pa-%pa] %pS\n",
821 		     &base, &end, (void *)_RET_IP_);
822 
823 	kmemleak_free_part_phys(base, size);
824 	return memblock_remove_range(&memblock.reserved, base, size);
825 }
826 
827 int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
828 {
829 	phys_addr_t end = base + size - 1;
830 
831 	memblock_dbg("memblock_reserve: [%pa-%pa] %pS\n",
832 		     &base, &end, (void *)_RET_IP_);
833 
834 	return memblock_add_range(&memblock.reserved, base, size, MAX_NUMNODES, 0);
835 }
836 
837 /**
838  * memblock_setclr_flag - set or clear flag for a memory region
839  * @base: base address of the region
840  * @size: size of the region
841  * @set: set or clear the flag
842  * @flag: the flag to udpate
843  *
844  * This function isolates region [@base, @base + @size), and sets/clears flag
845  *
846  * Return: 0 on success, -errno on failure.
847  */
848 static int __init_memblock memblock_setclr_flag(phys_addr_t base,
849 				phys_addr_t size, int set, int flag)
850 {
851 	struct memblock_type *type = &memblock.memory;
852 	int i, ret, start_rgn, end_rgn;
853 
854 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
855 	if (ret)
856 		return ret;
857 
858 	for (i = start_rgn; i < end_rgn; i++) {
859 		struct memblock_region *r = &type->regions[i];
860 
861 		if (set)
862 			r->flags |= flag;
863 		else
864 			r->flags &= ~flag;
865 	}
866 
867 	memblock_merge_regions(type);
868 	return 0;
869 }
870 
871 /**
872  * memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
873  * @base: the base phys addr of the region
874  * @size: the size of the region
875  *
876  * Return: 0 on success, -errno on failure.
877  */
878 int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
879 {
880 	return memblock_setclr_flag(base, size, 1, MEMBLOCK_HOTPLUG);
881 }
882 
883 /**
884  * memblock_clear_hotplug - Clear flag MEMBLOCK_HOTPLUG for a specified region.
885  * @base: the base phys addr of the region
886  * @size: the size of the region
887  *
888  * Return: 0 on success, -errno on failure.
889  */
890 int __init_memblock memblock_clear_hotplug(phys_addr_t base, phys_addr_t size)
891 {
892 	return memblock_setclr_flag(base, size, 0, MEMBLOCK_HOTPLUG);
893 }
894 
895 /**
896  * memblock_mark_mirror - Mark mirrored memory with flag MEMBLOCK_MIRROR.
897  * @base: the base phys addr of the region
898  * @size: the size of the region
899  *
900  * Return: 0 on success, -errno on failure.
901  */
902 int __init_memblock memblock_mark_mirror(phys_addr_t base, phys_addr_t size)
903 {
904 	system_has_some_mirror = true;
905 
906 	return memblock_setclr_flag(base, size, 1, MEMBLOCK_MIRROR);
907 }
908 
909 /**
910  * memblock_mark_nomap - Mark a memory region with flag MEMBLOCK_NOMAP.
911  * @base: the base phys addr of the region
912  * @size: the size of the region
913  *
914  * Return: 0 on success, -errno on failure.
915  */
916 int __init_memblock memblock_mark_nomap(phys_addr_t base, phys_addr_t size)
917 {
918 	return memblock_setclr_flag(base, size, 1, MEMBLOCK_NOMAP);
919 }
920 
921 /**
922  * memblock_clear_nomap - Clear flag MEMBLOCK_NOMAP for a specified region.
923  * @base: the base phys addr of the region
924  * @size: the size of the region
925  *
926  * Return: 0 on success, -errno on failure.
927  */
928 int __init_memblock memblock_clear_nomap(phys_addr_t base, phys_addr_t size)
929 {
930 	return memblock_setclr_flag(base, size, 0, MEMBLOCK_NOMAP);
931 }
932 
933 /**
934  * __next_reserved_mem_region - next function for for_each_reserved_region()
935  * @idx: pointer to u64 loop variable
936  * @out_start: ptr to phys_addr_t for start address of the region, can be %NULL
937  * @out_end: ptr to phys_addr_t for end address of the region, can be %NULL
938  *
939  * Iterate over all reserved memory regions.
940  */
941 void __init_memblock __next_reserved_mem_region(u64 *idx,
942 					   phys_addr_t *out_start,
943 					   phys_addr_t *out_end)
944 {
945 	struct memblock_type *type = &memblock.reserved;
946 
947 	if (*idx < type->cnt) {
948 		struct memblock_region *r = &type->regions[*idx];
949 		phys_addr_t base = r->base;
950 		phys_addr_t size = r->size;
951 
952 		if (out_start)
953 			*out_start = base;
954 		if (out_end)
955 			*out_end = base + size - 1;
956 
957 		*idx += 1;
958 		return;
959 	}
960 
961 	/* signal end of iteration */
962 	*idx = ULLONG_MAX;
963 }
964 
965 static bool should_skip_region(struct memblock_region *m, int nid, int flags)
966 {
967 	int m_nid = memblock_get_region_node(m);
968 
969 	/* only memory regions are associated with nodes, check it */
970 	if (nid != NUMA_NO_NODE && nid != m_nid)
971 		return true;
972 
973 	/* skip hotpluggable memory regions if needed */
974 	if (movable_node_is_enabled() && memblock_is_hotpluggable(m))
975 		return true;
976 
977 	/* if we want mirror memory skip non-mirror memory regions */
978 	if ((flags & MEMBLOCK_MIRROR) && !memblock_is_mirror(m))
979 		return true;
980 
981 	/* skip nomap memory unless we were asked for it explicitly */
982 	if (!(flags & MEMBLOCK_NOMAP) && memblock_is_nomap(m))
983 		return true;
984 
985 	return false;
986 }
987 
988 /**
989  * __next_mem_range - next function for for_each_free_mem_range() etc.
990  * @idx: pointer to u64 loop variable
991  * @nid: node selector, %NUMA_NO_NODE for all nodes
992  * @flags: pick from blocks based on memory attributes
993  * @type_a: pointer to memblock_type from where the range is taken
994  * @type_b: pointer to memblock_type which excludes memory from being taken
995  * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
996  * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
997  * @out_nid: ptr to int for nid of the range, can be %NULL
998  *
999  * Find the first area from *@idx which matches @nid, fill the out
1000  * parameters, and update *@idx for the next iteration.  The lower 32bit of
1001  * *@idx contains index into type_a and the upper 32bit indexes the
1002  * areas before each region in type_b.	For example, if type_b regions
1003  * look like the following,
1004  *
1005  *	0:[0-16), 1:[32-48), 2:[128-130)
1006  *
1007  * The upper 32bit indexes the following regions.
1008  *
1009  *	0:[0-0), 1:[16-32), 2:[48-128), 3:[130-MAX)
1010  *
1011  * As both region arrays are sorted, the function advances the two indices
1012  * in lockstep and returns each intersection.
1013  */
1014 void __init_memblock __next_mem_range(u64 *idx, int nid,
1015 				      enum memblock_flags flags,
1016 				      struct memblock_type *type_a,
1017 				      struct memblock_type *type_b,
1018 				      phys_addr_t *out_start,
1019 				      phys_addr_t *out_end, int *out_nid)
1020 {
1021 	int idx_a = *idx & 0xffffffff;
1022 	int idx_b = *idx >> 32;
1023 
1024 	if (WARN_ONCE(nid == MAX_NUMNODES,
1025 	"Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
1026 		nid = NUMA_NO_NODE;
1027 
1028 	for (; idx_a < type_a->cnt; idx_a++) {
1029 		struct memblock_region *m = &type_a->regions[idx_a];
1030 
1031 		phys_addr_t m_start = m->base;
1032 		phys_addr_t m_end = m->base + m->size;
1033 		int	    m_nid = memblock_get_region_node(m);
1034 
1035 		if (should_skip_region(m, nid, flags))
1036 			continue;
1037 
1038 		if (!type_b) {
1039 			if (out_start)
1040 				*out_start = m_start;
1041 			if (out_end)
1042 				*out_end = m_end;
1043 			if (out_nid)
1044 				*out_nid = m_nid;
1045 			idx_a++;
1046 			*idx = (u32)idx_a | (u64)idx_b << 32;
1047 			return;
1048 		}
1049 
1050 		/* scan areas before each reservation */
1051 		for (; idx_b < type_b->cnt + 1; idx_b++) {
1052 			struct memblock_region *r;
1053 			phys_addr_t r_start;
1054 			phys_addr_t r_end;
1055 
1056 			r = &type_b->regions[idx_b];
1057 			r_start = idx_b ? r[-1].base + r[-1].size : 0;
1058 			r_end = idx_b < type_b->cnt ?
1059 				r->base : PHYS_ADDR_MAX;
1060 
1061 			/*
1062 			 * if idx_b advanced past idx_a,
1063 			 * break out to advance idx_a
1064 			 */
1065 			if (r_start >= m_end)
1066 				break;
1067 			/* if the two regions intersect, we're done */
1068 			if (m_start < r_end) {
1069 				if (out_start)
1070 					*out_start =
1071 						max(m_start, r_start);
1072 				if (out_end)
1073 					*out_end = min(m_end, r_end);
1074 				if (out_nid)
1075 					*out_nid = m_nid;
1076 				/*
1077 				 * The region which ends first is
1078 				 * advanced for the next iteration.
1079 				 */
1080 				if (m_end <= r_end)
1081 					idx_a++;
1082 				else
1083 					idx_b++;
1084 				*idx = (u32)idx_a | (u64)idx_b << 32;
1085 				return;
1086 			}
1087 		}
1088 	}
1089 
1090 	/* signal end of iteration */
1091 	*idx = ULLONG_MAX;
1092 }
1093 
1094 /**
1095  * __next_mem_range_rev - generic next function for for_each_*_range_rev()
1096  *
1097  * @idx: pointer to u64 loop variable
1098  * @nid: node selector, %NUMA_NO_NODE for all nodes
1099  * @flags: pick from blocks based on memory attributes
1100  * @type_a: pointer to memblock_type from where the range is taken
1101  * @type_b: pointer to memblock_type which excludes memory from being taken
1102  * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
1103  * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
1104  * @out_nid: ptr to int for nid of the range, can be %NULL
1105  *
1106  * Finds the next range from type_a which is not marked as unsuitable
1107  * in type_b.
1108  *
1109  * Reverse of __next_mem_range().
1110  */
1111 void __init_memblock __next_mem_range_rev(u64 *idx, int nid,
1112 					  enum memblock_flags flags,
1113 					  struct memblock_type *type_a,
1114 					  struct memblock_type *type_b,
1115 					  phys_addr_t *out_start,
1116 					  phys_addr_t *out_end, int *out_nid)
1117 {
1118 	int idx_a = *idx & 0xffffffff;
1119 	int idx_b = *idx >> 32;
1120 
1121 	if (WARN_ONCE(nid == MAX_NUMNODES, "Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
1122 		nid = NUMA_NO_NODE;
1123 
1124 	if (*idx == (u64)ULLONG_MAX) {
1125 		idx_a = type_a->cnt - 1;
1126 		if (type_b != NULL)
1127 			idx_b = type_b->cnt;
1128 		else
1129 			idx_b = 0;
1130 	}
1131 
1132 	for (; idx_a >= 0; idx_a--) {
1133 		struct memblock_region *m = &type_a->regions[idx_a];
1134 
1135 		phys_addr_t m_start = m->base;
1136 		phys_addr_t m_end = m->base + m->size;
1137 		int m_nid = memblock_get_region_node(m);
1138 
1139 		if (should_skip_region(m, nid, flags))
1140 			continue;
1141 
1142 		if (!type_b) {
1143 			if (out_start)
1144 				*out_start = m_start;
1145 			if (out_end)
1146 				*out_end = m_end;
1147 			if (out_nid)
1148 				*out_nid = m_nid;
1149 			idx_a--;
1150 			*idx = (u32)idx_a | (u64)idx_b << 32;
1151 			return;
1152 		}
1153 
1154 		/* scan areas before each reservation */
1155 		for (; idx_b >= 0; idx_b--) {
1156 			struct memblock_region *r;
1157 			phys_addr_t r_start;
1158 			phys_addr_t r_end;
1159 
1160 			r = &type_b->regions[idx_b];
1161 			r_start = idx_b ? r[-1].base + r[-1].size : 0;
1162 			r_end = idx_b < type_b->cnt ?
1163 				r->base : PHYS_ADDR_MAX;
1164 			/*
1165 			 * if idx_b advanced past idx_a,
1166 			 * break out to advance idx_a
1167 			 */
1168 
1169 			if (r_end <= m_start)
1170 				break;
1171 			/* if the two regions intersect, we're done */
1172 			if (m_end > r_start) {
1173 				if (out_start)
1174 					*out_start = max(m_start, r_start);
1175 				if (out_end)
1176 					*out_end = min(m_end, r_end);
1177 				if (out_nid)
1178 					*out_nid = m_nid;
1179 				if (m_start >= r_start)
1180 					idx_a--;
1181 				else
1182 					idx_b--;
1183 				*idx = (u32)idx_a | (u64)idx_b << 32;
1184 				return;
1185 			}
1186 		}
1187 	}
1188 	/* signal end of iteration */
1189 	*idx = ULLONG_MAX;
1190 }
1191 
1192 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
1193 /*
1194  * Common iterator interface used to define for_each_mem_pfn_range().
1195  */
1196 void __init_memblock __next_mem_pfn_range(int *idx, int nid,
1197 				unsigned long *out_start_pfn,
1198 				unsigned long *out_end_pfn, int *out_nid)
1199 {
1200 	struct memblock_type *type = &memblock.memory;
1201 	struct memblock_region *r;
1202 
1203 	while (++*idx < type->cnt) {
1204 		r = &type->regions[*idx];
1205 
1206 		if (PFN_UP(r->base) >= PFN_DOWN(r->base + r->size))
1207 			continue;
1208 		if (nid == MAX_NUMNODES || nid == r->nid)
1209 			break;
1210 	}
1211 	if (*idx >= type->cnt) {
1212 		*idx = -1;
1213 		return;
1214 	}
1215 
1216 	if (out_start_pfn)
1217 		*out_start_pfn = PFN_UP(r->base);
1218 	if (out_end_pfn)
1219 		*out_end_pfn = PFN_DOWN(r->base + r->size);
1220 	if (out_nid)
1221 		*out_nid = r->nid;
1222 }
1223 
1224 /**
1225  * memblock_set_node - set node ID on memblock regions
1226  * @base: base of area to set node ID for
1227  * @size: size of area to set node ID for
1228  * @type: memblock type to set node ID for
1229  * @nid: node ID to set
1230  *
1231  * Set the nid of memblock @type regions in [@base, @base + @size) to @nid.
1232  * Regions which cross the area boundaries are split as necessary.
1233  *
1234  * Return:
1235  * 0 on success, -errno on failure.
1236  */
1237 int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
1238 				      struct memblock_type *type, int nid)
1239 {
1240 	int start_rgn, end_rgn;
1241 	int i, ret;
1242 
1243 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
1244 	if (ret)
1245 		return ret;
1246 
1247 	for (i = start_rgn; i < end_rgn; i++)
1248 		memblock_set_region_node(&type->regions[i], nid);
1249 
1250 	memblock_merge_regions(type);
1251 	return 0;
1252 }
1253 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
1254 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
1255 /**
1256  * __next_mem_pfn_range_in_zone - iterator for for_each_*_range_in_zone()
1257  *
1258  * @idx: pointer to u64 loop variable
1259  * @zone: zone in which all of the memory blocks reside
1260  * @out_spfn: ptr to ulong for start pfn of the range, can be %NULL
1261  * @out_epfn: ptr to ulong for end pfn of the range, can be %NULL
1262  *
1263  * This function is meant to be a zone/pfn specific wrapper for the
1264  * for_each_mem_range type iterators. Specifically they are used in the
1265  * deferred memory init routines and as such we were duplicating much of
1266  * this logic throughout the code. So instead of having it in multiple
1267  * locations it seemed like it would make more sense to centralize this to
1268  * one new iterator that does everything they need.
1269  */
1270 void __init_memblock
1271 __next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone,
1272 			     unsigned long *out_spfn, unsigned long *out_epfn)
1273 {
1274 	int zone_nid = zone_to_nid(zone);
1275 	phys_addr_t spa, epa;
1276 	int nid;
1277 
1278 	__next_mem_range(idx, zone_nid, MEMBLOCK_NONE,
1279 			 &memblock.memory, &memblock.reserved,
1280 			 &spa, &epa, &nid);
1281 
1282 	while (*idx != U64_MAX) {
1283 		unsigned long epfn = PFN_DOWN(epa);
1284 		unsigned long spfn = PFN_UP(spa);
1285 
1286 		/*
1287 		 * Verify the end is at least past the start of the zone and
1288 		 * that we have at least one PFN to initialize.
1289 		 */
1290 		if (zone->zone_start_pfn < epfn && spfn < epfn) {
1291 			/* if we went too far just stop searching */
1292 			if (zone_end_pfn(zone) <= spfn) {
1293 				*idx = U64_MAX;
1294 				break;
1295 			}
1296 
1297 			if (out_spfn)
1298 				*out_spfn = max(zone->zone_start_pfn, spfn);
1299 			if (out_epfn)
1300 				*out_epfn = min(zone_end_pfn(zone), epfn);
1301 
1302 			return;
1303 		}
1304 
1305 		__next_mem_range(idx, zone_nid, MEMBLOCK_NONE,
1306 				 &memblock.memory, &memblock.reserved,
1307 				 &spa, &epa, &nid);
1308 	}
1309 
1310 	/* signal end of iteration */
1311 	if (out_spfn)
1312 		*out_spfn = ULONG_MAX;
1313 	if (out_epfn)
1314 		*out_epfn = 0;
1315 }
1316 
1317 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
1318 
1319 /**
1320  * memblock_alloc_range_nid - allocate boot memory block
1321  * @size: size of memory block to be allocated in bytes
1322  * @align: alignment of the region and block's size
1323  * @start: the lower bound of the memory region to allocate (phys address)
1324  * @end: the upper bound of the memory region to allocate (phys address)
1325  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1326  *
1327  * The allocation is performed from memory region limited by
1328  * memblock.current_limit if @max_addr == %MEMBLOCK_ALLOC_ACCESSIBLE.
1329  *
1330  * If the specified node can not hold the requested memory the
1331  * allocation falls back to any node in the system
1332  *
1333  * For systems with memory mirroring, the allocation is attempted first
1334  * from the regions with mirroring enabled and then retried from any
1335  * memory region.
1336  *
1337  * In addition, function sets the min_count to 0 using kmemleak_alloc_phys for
1338  * allocated boot memory block, so that it is never reported as leaks.
1339  *
1340  * Return:
1341  * Physical address of allocated memory block on success, %0 on failure.
1342  */
1343 static phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size,
1344 					phys_addr_t align, phys_addr_t start,
1345 					phys_addr_t end, int nid)
1346 {
1347 	enum memblock_flags flags = choose_memblock_flags();
1348 	phys_addr_t found;
1349 
1350 	if (WARN_ONCE(nid == MAX_NUMNODES, "Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
1351 		nid = NUMA_NO_NODE;
1352 
1353 	if (!align) {
1354 		/* Can't use WARNs this early in boot on powerpc */
1355 		dump_stack();
1356 		align = SMP_CACHE_BYTES;
1357 	}
1358 
1359 	if (end > memblock.current_limit)
1360 		end = memblock.current_limit;
1361 
1362 again:
1363 	found = memblock_find_in_range_node(size, align, start, end, nid,
1364 					    flags);
1365 	if (found && !memblock_reserve(found, size))
1366 		goto done;
1367 
1368 	if (nid != NUMA_NO_NODE) {
1369 		found = memblock_find_in_range_node(size, align, start,
1370 						    end, NUMA_NO_NODE,
1371 						    flags);
1372 		if (found && !memblock_reserve(found, size))
1373 			goto done;
1374 	}
1375 
1376 	if (flags & MEMBLOCK_MIRROR) {
1377 		flags &= ~MEMBLOCK_MIRROR;
1378 		pr_warn("Could not allocate %pap bytes of mirrored memory\n",
1379 			&size);
1380 		goto again;
1381 	}
1382 
1383 	return 0;
1384 
1385 done:
1386 	/* Skip kmemleak for kasan_init() due to high volume. */
1387 	if (end != MEMBLOCK_ALLOC_KASAN)
1388 		/*
1389 		 * The min_count is set to 0 so that memblock allocated
1390 		 * blocks are never reported as leaks. This is because many
1391 		 * of these blocks are only referred via the physical
1392 		 * address which is not looked up by kmemleak.
1393 		 */
1394 		kmemleak_alloc_phys(found, size, 0, 0);
1395 
1396 	return found;
1397 }
1398 
1399 /**
1400  * memblock_phys_alloc_range - allocate a memory block inside specified range
1401  * @size: size of memory block to be allocated in bytes
1402  * @align: alignment of the region and block's size
1403  * @start: the lower bound of the memory region to allocate (physical address)
1404  * @end: the upper bound of the memory region to allocate (physical address)
1405  *
1406  * Allocate @size bytes in the between @start and @end.
1407  *
1408  * Return: physical address of the allocated memory block on success,
1409  * %0 on failure.
1410  */
1411 phys_addr_t __init memblock_phys_alloc_range(phys_addr_t size,
1412 					     phys_addr_t align,
1413 					     phys_addr_t start,
1414 					     phys_addr_t end)
1415 {
1416 	return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE);
1417 }
1418 
1419 /**
1420  * memblock_phys_alloc_try_nid - allocate a memory block from specified MUMA node
1421  * @size: size of memory block to be allocated in bytes
1422  * @align: alignment of the region and block's size
1423  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1424  *
1425  * Allocates memory block from the specified NUMA node. If the node
1426  * has no available memory, attempts to allocated from any node in the
1427  * system.
1428  *
1429  * Return: physical address of the allocated memory block on success,
1430  * %0 on failure.
1431  */
1432 phys_addr_t __init memblock_phys_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
1433 {
1434 	return memblock_alloc_range_nid(size, align, 0,
1435 					MEMBLOCK_ALLOC_ACCESSIBLE, nid);
1436 }
1437 
1438 /**
1439  * memblock_alloc_internal - allocate boot memory block
1440  * @size: size of memory block to be allocated in bytes
1441  * @align: alignment of the region and block's size
1442  * @min_addr: the lower bound of the memory region to allocate (phys address)
1443  * @max_addr: the upper bound of the memory region to allocate (phys address)
1444  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1445  *
1446  * Allocates memory block using memblock_alloc_range_nid() and
1447  * converts the returned physical address to virtual.
1448  *
1449  * The @min_addr limit is dropped if it can not be satisfied and the allocation
1450  * will fall back to memory below @min_addr. Other constraints, such
1451  * as node and mirrored memory will be handled again in
1452  * memblock_alloc_range_nid().
1453  *
1454  * Return:
1455  * Virtual address of allocated memory block on success, NULL on failure.
1456  */
1457 static void * __init memblock_alloc_internal(
1458 				phys_addr_t size, phys_addr_t align,
1459 				phys_addr_t min_addr, phys_addr_t max_addr,
1460 				int nid)
1461 {
1462 	phys_addr_t alloc;
1463 
1464 	/*
1465 	 * Detect any accidental use of these APIs after slab is ready, as at
1466 	 * this moment memblock may be deinitialized already and its
1467 	 * internal data may be destroyed (after execution of memblock_free_all)
1468 	 */
1469 	if (WARN_ON_ONCE(slab_is_available()))
1470 		return kzalloc_node(size, GFP_NOWAIT, nid);
1471 
1472 	alloc = memblock_alloc_range_nid(size, align, min_addr, max_addr, nid);
1473 
1474 	/* retry allocation without lower limit */
1475 	if (!alloc && min_addr)
1476 		alloc = memblock_alloc_range_nid(size, align, 0, max_addr, nid);
1477 
1478 	if (!alloc)
1479 		return NULL;
1480 
1481 	return phys_to_virt(alloc);
1482 }
1483 
1484 /**
1485  * memblock_alloc_try_nid_raw - allocate boot memory block without zeroing
1486  * memory and without panicking
1487  * @size: size of memory block to be allocated in bytes
1488  * @align: alignment of the region and block's size
1489  * @min_addr: the lower bound of the memory region from where the allocation
1490  *	  is preferred (phys address)
1491  * @max_addr: the upper bound of the memory region from where the allocation
1492  *	      is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to
1493  *	      allocate only from memory limited by memblock.current_limit value
1494  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1495  *
1496  * Public function, provides additional debug information (including caller
1497  * info), if enabled. Does not zero allocated memory, does not panic if request
1498  * cannot be satisfied.
1499  *
1500  * Return:
1501  * Virtual address of allocated memory block on success, NULL on failure.
1502  */
1503 void * __init memblock_alloc_try_nid_raw(
1504 			phys_addr_t size, phys_addr_t align,
1505 			phys_addr_t min_addr, phys_addr_t max_addr,
1506 			int nid)
1507 {
1508 	void *ptr;
1509 
1510 	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
1511 		     __func__, (u64)size, (u64)align, nid, &min_addr,
1512 		     &max_addr, (void *)_RET_IP_);
1513 
1514 	ptr = memblock_alloc_internal(size, align,
1515 					   min_addr, max_addr, nid);
1516 	if (ptr && size > 0)
1517 		page_init_poison(ptr, size);
1518 
1519 	return ptr;
1520 }
1521 
1522 /**
1523  * memblock_alloc_try_nid - allocate boot memory block
1524  * @size: size of memory block to be allocated in bytes
1525  * @align: alignment of the region and block's size
1526  * @min_addr: the lower bound of the memory region from where the allocation
1527  *	  is preferred (phys address)
1528  * @max_addr: the upper bound of the memory region from where the allocation
1529  *	      is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to
1530  *	      allocate only from memory limited by memblock.current_limit value
1531  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1532  *
1533  * Public function, provides additional debug information (including caller
1534  * info), if enabled. This function zeroes the allocated memory.
1535  *
1536  * Return:
1537  * Virtual address of allocated memory block on success, NULL on failure.
1538  */
1539 void * __init memblock_alloc_try_nid(
1540 			phys_addr_t size, phys_addr_t align,
1541 			phys_addr_t min_addr, phys_addr_t max_addr,
1542 			int nid)
1543 {
1544 	void *ptr;
1545 
1546 	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
1547 		     __func__, (u64)size, (u64)align, nid, &min_addr,
1548 		     &max_addr, (void *)_RET_IP_);
1549 	ptr = memblock_alloc_internal(size, align,
1550 					   min_addr, max_addr, nid);
1551 	if (ptr)
1552 		memset(ptr, 0, size);
1553 
1554 	return ptr;
1555 }
1556 
1557 /**
1558  * __memblock_free_late - free pages directly to buddy allocator
1559  * @base: phys starting address of the  boot memory block
1560  * @size: size of the boot memory block in bytes
1561  *
1562  * This is only useful when the memblock allocator has already been torn
1563  * down, but we are still initializing the system.  Pages are released directly
1564  * to the buddy allocator.
1565  */
1566 void __init __memblock_free_late(phys_addr_t base, phys_addr_t size)
1567 {
1568 	phys_addr_t cursor, end;
1569 
1570 	end = base + size - 1;
1571 	memblock_dbg("%s: [%pa-%pa] %pS\n",
1572 		     __func__, &base, &end, (void *)_RET_IP_);
1573 	kmemleak_free_part_phys(base, size);
1574 	cursor = PFN_UP(base);
1575 	end = PFN_DOWN(base + size);
1576 
1577 	for (; cursor < end; cursor++) {
1578 		memblock_free_pages(pfn_to_page(cursor), cursor, 0);
1579 		totalram_pages_inc();
1580 	}
1581 }
1582 
1583 /*
1584  * Remaining API functions
1585  */
1586 
1587 phys_addr_t __init_memblock memblock_phys_mem_size(void)
1588 {
1589 	return memblock.memory.total_size;
1590 }
1591 
1592 phys_addr_t __init_memblock memblock_reserved_size(void)
1593 {
1594 	return memblock.reserved.total_size;
1595 }
1596 
1597 phys_addr_t __init memblock_mem_size(unsigned long limit_pfn)
1598 {
1599 	unsigned long pages = 0;
1600 	struct memblock_region *r;
1601 	unsigned long start_pfn, end_pfn;
1602 
1603 	for_each_memblock(memory, r) {
1604 		start_pfn = memblock_region_memory_base_pfn(r);
1605 		end_pfn = memblock_region_memory_end_pfn(r);
1606 		start_pfn = min_t(unsigned long, start_pfn, limit_pfn);
1607 		end_pfn = min_t(unsigned long, end_pfn, limit_pfn);
1608 		pages += end_pfn - start_pfn;
1609 	}
1610 
1611 	return PFN_PHYS(pages);
1612 }
1613 
1614 /* lowest address */
1615 phys_addr_t __init_memblock memblock_start_of_DRAM(void)
1616 {
1617 	return memblock.memory.regions[0].base;
1618 }
1619 
1620 phys_addr_t __init_memblock memblock_end_of_DRAM(void)
1621 {
1622 	int idx = memblock.memory.cnt - 1;
1623 
1624 	return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
1625 }
1626 
1627 static phys_addr_t __init_memblock __find_max_addr(phys_addr_t limit)
1628 {
1629 	phys_addr_t max_addr = PHYS_ADDR_MAX;
1630 	struct memblock_region *r;
1631 
1632 	/*
1633 	 * translate the memory @limit size into the max address within one of
1634 	 * the memory memblock regions, if the @limit exceeds the total size
1635 	 * of those regions, max_addr will keep original value PHYS_ADDR_MAX
1636 	 */
1637 	for_each_memblock(memory, r) {
1638 		if (limit <= r->size) {
1639 			max_addr = r->base + limit;
1640 			break;
1641 		}
1642 		limit -= r->size;
1643 	}
1644 
1645 	return max_addr;
1646 }
1647 
1648 void __init memblock_enforce_memory_limit(phys_addr_t limit)
1649 {
1650 	phys_addr_t max_addr = PHYS_ADDR_MAX;
1651 
1652 	if (!limit)
1653 		return;
1654 
1655 	max_addr = __find_max_addr(limit);
1656 
1657 	/* @limit exceeds the total size of the memory, do nothing */
1658 	if (max_addr == PHYS_ADDR_MAX)
1659 		return;
1660 
1661 	/* truncate both memory and reserved regions */
1662 	memblock_remove_range(&memblock.memory, max_addr,
1663 			      PHYS_ADDR_MAX);
1664 	memblock_remove_range(&memblock.reserved, max_addr,
1665 			      PHYS_ADDR_MAX);
1666 }
1667 
1668 void __init memblock_cap_memory_range(phys_addr_t base, phys_addr_t size)
1669 {
1670 	int start_rgn, end_rgn;
1671 	int i, ret;
1672 
1673 	if (!size)
1674 		return;
1675 
1676 	ret = memblock_isolate_range(&memblock.memory, base, size,
1677 						&start_rgn, &end_rgn);
1678 	if (ret)
1679 		return;
1680 
1681 	/* remove all the MAP regions */
1682 	for (i = memblock.memory.cnt - 1; i >= end_rgn; i--)
1683 		if (!memblock_is_nomap(&memblock.memory.regions[i]))
1684 			memblock_remove_region(&memblock.memory, i);
1685 
1686 	for (i = start_rgn - 1; i >= 0; i--)
1687 		if (!memblock_is_nomap(&memblock.memory.regions[i]))
1688 			memblock_remove_region(&memblock.memory, i);
1689 
1690 	/* truncate the reserved regions */
1691 	memblock_remove_range(&memblock.reserved, 0, base);
1692 	memblock_remove_range(&memblock.reserved,
1693 			base + size, PHYS_ADDR_MAX);
1694 }
1695 
1696 void __init memblock_mem_limit_remove_map(phys_addr_t limit)
1697 {
1698 	phys_addr_t max_addr;
1699 
1700 	if (!limit)
1701 		return;
1702 
1703 	max_addr = __find_max_addr(limit);
1704 
1705 	/* @limit exceeds the total size of the memory, do nothing */
1706 	if (max_addr == PHYS_ADDR_MAX)
1707 		return;
1708 
1709 	memblock_cap_memory_range(0, max_addr);
1710 }
1711 
1712 static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
1713 {
1714 	unsigned int left = 0, right = type->cnt;
1715 
1716 	do {
1717 		unsigned int mid = (right + left) / 2;
1718 
1719 		if (addr < type->regions[mid].base)
1720 			right = mid;
1721 		else if (addr >= (type->regions[mid].base +
1722 				  type->regions[mid].size))
1723 			left = mid + 1;
1724 		else
1725 			return mid;
1726 	} while (left < right);
1727 	return -1;
1728 }
1729 
1730 bool __init_memblock memblock_is_reserved(phys_addr_t addr)
1731 {
1732 	return memblock_search(&memblock.reserved, addr) != -1;
1733 }
1734 
1735 bool __init_memblock memblock_is_memory(phys_addr_t addr)
1736 {
1737 	return memblock_search(&memblock.memory, addr) != -1;
1738 }
1739 
1740 bool __init_memblock memblock_is_map_memory(phys_addr_t addr)
1741 {
1742 	int i = memblock_search(&memblock.memory, addr);
1743 
1744 	if (i == -1)
1745 		return false;
1746 	return !memblock_is_nomap(&memblock.memory.regions[i]);
1747 }
1748 
1749 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
1750 int __init_memblock memblock_search_pfn_nid(unsigned long pfn,
1751 			 unsigned long *start_pfn, unsigned long *end_pfn)
1752 {
1753 	struct memblock_type *type = &memblock.memory;
1754 	int mid = memblock_search(type, PFN_PHYS(pfn));
1755 
1756 	if (mid == -1)
1757 		return -1;
1758 
1759 	*start_pfn = PFN_DOWN(type->regions[mid].base);
1760 	*end_pfn = PFN_DOWN(type->regions[mid].base + type->regions[mid].size);
1761 
1762 	return type->regions[mid].nid;
1763 }
1764 #endif
1765 
1766 /**
1767  * memblock_is_region_memory - check if a region is a subset of memory
1768  * @base: base of region to check
1769  * @size: size of region to check
1770  *
1771  * Check if the region [@base, @base + @size) is a subset of a memory block.
1772  *
1773  * Return:
1774  * 0 if false, non-zero if true
1775  */
1776 bool __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
1777 {
1778 	int idx = memblock_search(&memblock.memory, base);
1779 	phys_addr_t end = base + memblock_cap_size(base, &size);
1780 
1781 	if (idx == -1)
1782 		return false;
1783 	return (memblock.memory.regions[idx].base +
1784 		 memblock.memory.regions[idx].size) >= end;
1785 }
1786 
1787 /**
1788  * memblock_is_region_reserved - check if a region intersects reserved memory
1789  * @base: base of region to check
1790  * @size: size of region to check
1791  *
1792  * Check if the region [@base, @base + @size) intersects a reserved
1793  * memory block.
1794  *
1795  * Return:
1796  * True if they intersect, false if not.
1797  */
1798 bool __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
1799 {
1800 	memblock_cap_size(base, &size);
1801 	return memblock_overlaps_region(&memblock.reserved, base, size);
1802 }
1803 
1804 void __init_memblock memblock_trim_memory(phys_addr_t align)
1805 {
1806 	phys_addr_t start, end, orig_start, orig_end;
1807 	struct memblock_region *r;
1808 
1809 	for_each_memblock(memory, r) {
1810 		orig_start = r->base;
1811 		orig_end = r->base + r->size;
1812 		start = round_up(orig_start, align);
1813 		end = round_down(orig_end, align);
1814 
1815 		if (start == orig_start && end == orig_end)
1816 			continue;
1817 
1818 		if (start < end) {
1819 			r->base = start;
1820 			r->size = end - start;
1821 		} else {
1822 			memblock_remove_region(&memblock.memory,
1823 					       r - memblock.memory.regions);
1824 			r--;
1825 		}
1826 	}
1827 }
1828 
1829 void __init_memblock memblock_set_current_limit(phys_addr_t limit)
1830 {
1831 	memblock.current_limit = limit;
1832 }
1833 
1834 phys_addr_t __init_memblock memblock_get_current_limit(void)
1835 {
1836 	return memblock.current_limit;
1837 }
1838 
1839 static void __init_memblock memblock_dump(struct memblock_type *type)
1840 {
1841 	phys_addr_t base, end, size;
1842 	enum memblock_flags flags;
1843 	int idx;
1844 	struct memblock_region *rgn;
1845 
1846 	pr_info(" %s.cnt  = 0x%lx\n", type->name, type->cnt);
1847 
1848 	for_each_memblock_type(idx, type, rgn) {
1849 		char nid_buf[32] = "";
1850 
1851 		base = rgn->base;
1852 		size = rgn->size;
1853 		end = base + size - 1;
1854 		flags = rgn->flags;
1855 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
1856 		if (memblock_get_region_node(rgn) != MAX_NUMNODES)
1857 			snprintf(nid_buf, sizeof(nid_buf), " on node %d",
1858 				 memblock_get_region_node(rgn));
1859 #endif
1860 		pr_info(" %s[%#x]\t[%pa-%pa], %pa bytes%s flags: %#x\n",
1861 			type->name, idx, &base, &end, &size, nid_buf, flags);
1862 	}
1863 }
1864 
1865 void __init_memblock __memblock_dump_all(void)
1866 {
1867 	pr_info("MEMBLOCK configuration:\n");
1868 	pr_info(" memory size = %pa reserved size = %pa\n",
1869 		&memblock.memory.total_size,
1870 		&memblock.reserved.total_size);
1871 
1872 	memblock_dump(&memblock.memory);
1873 	memblock_dump(&memblock.reserved);
1874 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
1875 	memblock_dump(&memblock.physmem);
1876 #endif
1877 }
1878 
1879 void __init memblock_allow_resize(void)
1880 {
1881 	memblock_can_resize = 1;
1882 }
1883 
1884 static int __init early_memblock(char *p)
1885 {
1886 	if (p && strstr(p, "debug"))
1887 		memblock_debug = 1;
1888 	return 0;
1889 }
1890 early_param("memblock", early_memblock);
1891 
1892 static void __init __free_pages_memory(unsigned long start, unsigned long end)
1893 {
1894 	int order;
1895 
1896 	while (start < end) {
1897 		order = min(MAX_ORDER - 1UL, __ffs(start));
1898 
1899 		while (start + (1UL << order) > end)
1900 			order--;
1901 
1902 		memblock_free_pages(pfn_to_page(start), start, order);
1903 
1904 		start += (1UL << order);
1905 	}
1906 }
1907 
1908 static unsigned long __init __free_memory_core(phys_addr_t start,
1909 				 phys_addr_t end)
1910 {
1911 	unsigned long start_pfn = PFN_UP(start);
1912 	unsigned long end_pfn = min_t(unsigned long,
1913 				      PFN_DOWN(end), max_low_pfn);
1914 
1915 	if (start_pfn >= end_pfn)
1916 		return 0;
1917 
1918 	__free_pages_memory(start_pfn, end_pfn);
1919 
1920 	return end_pfn - start_pfn;
1921 }
1922 
1923 static unsigned long __init free_low_memory_core_early(void)
1924 {
1925 	unsigned long count = 0;
1926 	phys_addr_t start, end;
1927 	u64 i;
1928 
1929 	memblock_clear_hotplug(0, -1);
1930 
1931 	for_each_reserved_mem_region(i, &start, &end)
1932 		reserve_bootmem_region(start, end);
1933 
1934 	/*
1935 	 * We need to use NUMA_NO_NODE instead of NODE_DATA(0)->node_id
1936 	 *  because in some case like Node0 doesn't have RAM installed
1937 	 *  low ram will be on Node1
1938 	 */
1939 	for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE, &start, &end,
1940 				NULL)
1941 		count += __free_memory_core(start, end);
1942 
1943 	return count;
1944 }
1945 
1946 static int reset_managed_pages_done __initdata;
1947 
1948 void reset_node_managed_pages(pg_data_t *pgdat)
1949 {
1950 	struct zone *z;
1951 
1952 	for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
1953 		atomic_long_set(&z->managed_pages, 0);
1954 }
1955 
1956 void __init reset_all_zones_managed_pages(void)
1957 {
1958 	struct pglist_data *pgdat;
1959 
1960 	if (reset_managed_pages_done)
1961 		return;
1962 
1963 	for_each_online_pgdat(pgdat)
1964 		reset_node_managed_pages(pgdat);
1965 
1966 	reset_managed_pages_done = 1;
1967 }
1968 
1969 /**
1970  * memblock_free_all - release free pages to the buddy allocator
1971  *
1972  * Return: the number of pages actually released.
1973  */
1974 unsigned long __init memblock_free_all(void)
1975 {
1976 	unsigned long pages;
1977 
1978 	reset_all_zones_managed_pages();
1979 
1980 	pages = free_low_memory_core_early();
1981 	totalram_pages_add(pages);
1982 
1983 	return pages;
1984 }
1985 
1986 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_ARCH_KEEP_MEMBLOCK)
1987 
1988 static int memblock_debug_show(struct seq_file *m, void *private)
1989 {
1990 	struct memblock_type *type = m->private;
1991 	struct memblock_region *reg;
1992 	int i;
1993 	phys_addr_t end;
1994 
1995 	for (i = 0; i < type->cnt; i++) {
1996 		reg = &type->regions[i];
1997 		end = reg->base + reg->size - 1;
1998 
1999 		seq_printf(m, "%4d: ", i);
2000 		seq_printf(m, "%pa..%pa\n", &reg->base, &end);
2001 	}
2002 	return 0;
2003 }
2004 DEFINE_SHOW_ATTRIBUTE(memblock_debug);
2005 
2006 static int __init memblock_init_debugfs(void)
2007 {
2008 	struct dentry *root = debugfs_create_dir("memblock", NULL);
2009 
2010 	debugfs_create_file("memory", 0444, root,
2011 			    &memblock.memory, &memblock_debug_fops);
2012 	debugfs_create_file("reserved", 0444, root,
2013 			    &memblock.reserved, &memblock_debug_fops);
2014 #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
2015 	debugfs_create_file("physmem", 0444, root,
2016 			    &memblock.physmem, &memblock_debug_fops);
2017 #endif
2018 
2019 	return 0;
2020 }
2021 __initcall(memblock_init_debugfs);
2022 
2023 #endif /* CONFIG_DEBUG_FS */
2024