xref: /openbmc/linux/mm/memblock.c (revision 278d3ba6)
1  // SPDX-License-Identifier: GPL-2.0-or-later
2  /*
3   * Procedures for maintaining information about logical memory blocks.
4   *
5   * Peter Bergner, IBM Corp.	June 2001.
6   * Copyright (C) 2001 Peter Bergner.
7   */
8  
9  #include <linux/kernel.h>
10  #include <linux/slab.h>
11  #include <linux/init.h>
12  #include <linux/bitops.h>
13  #include <linux/poison.h>
14  #include <linux/pfn.h>
15  #include <linux/debugfs.h>
16  #include <linux/kmemleak.h>
17  #include <linux/seq_file.h>
18  #include <linux/memblock.h>
19  
20  #include <asm/sections.h>
21  #include <linux/io.h>
22  
23  #include "internal.h"
24  
25  #define INIT_MEMBLOCK_REGIONS			128
26  #define INIT_PHYSMEM_REGIONS			4
27  
28  #ifndef INIT_MEMBLOCK_RESERVED_REGIONS
29  # define INIT_MEMBLOCK_RESERVED_REGIONS		INIT_MEMBLOCK_REGIONS
30  #endif
31  
32  #ifndef INIT_MEMBLOCK_MEMORY_REGIONS
33  #define INIT_MEMBLOCK_MEMORY_REGIONS		INIT_MEMBLOCK_REGIONS
34  #endif
35  
36  /**
37   * DOC: memblock overview
38   *
39   * Memblock is a method of managing memory regions during the early
40   * boot period when the usual kernel memory allocators are not up and
41   * running.
42   *
43   * Memblock views the system memory as collections of contiguous
44   * regions. There are several types of these collections:
45   *
46   * * ``memory`` - describes the physical memory available to the
47   *   kernel; this may differ from the actual physical memory installed
48   *   in the system, for instance when the memory is restricted with
49   *   ``mem=`` command line parameter
50   * * ``reserved`` - describes the regions that were allocated
51   * * ``physmem`` - describes the actual physical memory available during
52   *   boot regardless of the possible restrictions and memory hot(un)plug;
53   *   the ``physmem`` type is only available on some architectures.
54   *
55   * Each region is represented by struct memblock_region that
56   * defines the region extents, its attributes and NUMA node id on NUMA
57   * systems. Every memory type is described by the struct memblock_type
58   * which contains an array of memory regions along with
59   * the allocator metadata. The "memory" and "reserved" types are nicely
60   * wrapped with struct memblock. This structure is statically
61   * initialized at build time. The region arrays are initially sized to
62   * %INIT_MEMBLOCK_MEMORY_REGIONS for "memory" and
63   * %INIT_MEMBLOCK_RESERVED_REGIONS for "reserved". The region array
64   * for "physmem" is initially sized to %INIT_PHYSMEM_REGIONS.
65   * The memblock_allow_resize() enables automatic resizing of the region
66   * arrays during addition of new regions. This feature should be used
67   * with care so that memory allocated for the region array will not
68   * overlap with areas that should be reserved, for example initrd.
69   *
70   * The early architecture setup should tell memblock what the physical
71   * memory layout is by using memblock_add() or memblock_add_node()
72   * functions. The first function does not assign the region to a NUMA
73   * node and it is appropriate for UMA systems. Yet, it is possible to
74   * use it on NUMA systems as well and assign the region to a NUMA node
75   * later in the setup process using memblock_set_node(). The
76   * memblock_add_node() performs such an assignment directly.
77   *
78   * Once memblock is setup the memory can be allocated using one of the
79   * API variants:
80   *
81   * * memblock_phys_alloc*() - these functions return the **physical**
82   *   address of the allocated memory
83   * * memblock_alloc*() - these functions return the **virtual** address
84   *   of the allocated memory.
85   *
86   * Note, that both API variants use implicit assumptions about allowed
87   * memory ranges and the fallback methods. Consult the documentation
88   * of memblock_alloc_internal() and memblock_alloc_range_nid()
89   * functions for more elaborate description.
90   *
91   * As the system boot progresses, the architecture specific mem_init()
92   * function frees all the memory to the buddy page allocator.
93   *
94   * Unless an architecture enables %CONFIG_ARCH_KEEP_MEMBLOCK, the
95   * memblock data structures (except "physmem") will be discarded after the
96   * system initialization completes.
97   */
98  
99  #ifndef CONFIG_NUMA
100  struct pglist_data __refdata contig_page_data;
101  EXPORT_SYMBOL(contig_page_data);
102  #endif
103  
104  unsigned long max_low_pfn;
105  unsigned long min_low_pfn;
106  unsigned long max_pfn;
107  unsigned long long max_possible_pfn;
108  
109  static struct memblock_region memblock_memory_init_regions[INIT_MEMBLOCK_MEMORY_REGIONS] __initdata_memblock;
110  static struct memblock_region memblock_reserved_init_regions[INIT_MEMBLOCK_RESERVED_REGIONS] __initdata_memblock;
111  #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
112  static struct memblock_region memblock_physmem_init_regions[INIT_PHYSMEM_REGIONS];
113  #endif
114  
115  struct memblock memblock __initdata_memblock = {
116  	.memory.regions		= memblock_memory_init_regions,
117  	.memory.cnt		= 1,	/* empty dummy entry */
118  	.memory.max		= INIT_MEMBLOCK_MEMORY_REGIONS,
119  	.memory.name		= "memory",
120  
121  	.reserved.regions	= memblock_reserved_init_regions,
122  	.reserved.cnt		= 1,	/* empty dummy entry */
123  	.reserved.max		= INIT_MEMBLOCK_RESERVED_REGIONS,
124  	.reserved.name		= "reserved",
125  
126  	.bottom_up		= false,
127  	.current_limit		= MEMBLOCK_ALLOC_ANYWHERE,
128  };
129  
130  #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
131  struct memblock_type physmem = {
132  	.regions		= memblock_physmem_init_regions,
133  	.cnt			= 1,	/* empty dummy entry */
134  	.max			= INIT_PHYSMEM_REGIONS,
135  	.name			= "physmem",
136  };
137  #endif
138  
139  /*
140   * keep a pointer to &memblock.memory in the text section to use it in
141   * __next_mem_range() and its helpers.
142   *  For architectures that do not keep memblock data after init, this
143   * pointer will be reset to NULL at memblock_discard()
144   */
145  static __refdata struct memblock_type *memblock_memory = &memblock.memory;
146  
147  #define for_each_memblock_type(i, memblock_type, rgn)			\
148  	for (i = 0, rgn = &memblock_type->regions[0];			\
149  	     i < memblock_type->cnt;					\
150  	     i++, rgn = &memblock_type->regions[i])
151  
152  #define memblock_dbg(fmt, ...)						\
153  	do {								\
154  		if (memblock_debug)					\
155  			pr_info(fmt, ##__VA_ARGS__);			\
156  	} while (0)
157  
158  static int memblock_debug __initdata_memblock;
159  static bool system_has_some_mirror __initdata_memblock = false;
160  static int memblock_can_resize __initdata_memblock;
161  static int memblock_memory_in_slab __initdata_memblock = 0;
162  static int memblock_reserved_in_slab __initdata_memblock = 0;
163  
164  static enum memblock_flags __init_memblock choose_memblock_flags(void)
165  {
166  	return system_has_some_mirror ? MEMBLOCK_MIRROR : MEMBLOCK_NONE;
167  }
168  
169  /* adjust *@size so that (@base + *@size) doesn't overflow, return new size */
170  static inline phys_addr_t memblock_cap_size(phys_addr_t base, phys_addr_t *size)
171  {
172  	return *size = min(*size, PHYS_ADDR_MAX - base);
173  }
174  
175  /*
176   * Address comparison utilities
177   */
178  static unsigned long __init_memblock memblock_addrs_overlap(phys_addr_t base1, phys_addr_t size1,
179  				       phys_addr_t base2, phys_addr_t size2)
180  {
181  	return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
182  }
183  
184  bool __init_memblock memblock_overlaps_region(struct memblock_type *type,
185  					phys_addr_t base, phys_addr_t size)
186  {
187  	unsigned long i;
188  
189  	memblock_cap_size(base, &size);
190  
191  	for (i = 0; i < type->cnt; i++)
192  		if (memblock_addrs_overlap(base, size, type->regions[i].base,
193  					   type->regions[i].size))
194  			break;
195  	return i < type->cnt;
196  }
197  
198  /**
199   * __memblock_find_range_bottom_up - find free area utility in bottom-up
200   * @start: start of candidate range
201   * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
202   *       %MEMBLOCK_ALLOC_ACCESSIBLE
203   * @size: size of free area to find
204   * @align: alignment of free area to find
205   * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
206   * @flags: pick from blocks based on memory attributes
207   *
208   * Utility called from memblock_find_in_range_node(), find free area bottom-up.
209   *
210   * Return:
211   * Found address on success, 0 on failure.
212   */
213  static phys_addr_t __init_memblock
214  __memblock_find_range_bottom_up(phys_addr_t start, phys_addr_t end,
215  				phys_addr_t size, phys_addr_t align, int nid,
216  				enum memblock_flags flags)
217  {
218  	phys_addr_t this_start, this_end, cand;
219  	u64 i;
220  
221  	for_each_free_mem_range(i, nid, flags, &this_start, &this_end, NULL) {
222  		this_start = clamp(this_start, start, end);
223  		this_end = clamp(this_end, start, end);
224  
225  		cand = round_up(this_start, align);
226  		if (cand < this_end && this_end - cand >= size)
227  			return cand;
228  	}
229  
230  	return 0;
231  }
232  
233  /**
234   * __memblock_find_range_top_down - find free area utility, in top-down
235   * @start: start of candidate range
236   * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
237   *       %MEMBLOCK_ALLOC_ACCESSIBLE
238   * @size: size of free area to find
239   * @align: alignment of free area to find
240   * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
241   * @flags: pick from blocks based on memory attributes
242   *
243   * Utility called from memblock_find_in_range_node(), find free area top-down.
244   *
245   * Return:
246   * Found address on success, 0 on failure.
247   */
248  static phys_addr_t __init_memblock
249  __memblock_find_range_top_down(phys_addr_t start, phys_addr_t end,
250  			       phys_addr_t size, phys_addr_t align, int nid,
251  			       enum memblock_flags flags)
252  {
253  	phys_addr_t this_start, this_end, cand;
254  	u64 i;
255  
256  	for_each_free_mem_range_reverse(i, nid, flags, &this_start, &this_end,
257  					NULL) {
258  		this_start = clamp(this_start, start, end);
259  		this_end = clamp(this_end, start, end);
260  
261  		if (this_end < size)
262  			continue;
263  
264  		cand = round_down(this_end - size, align);
265  		if (cand >= this_start)
266  			return cand;
267  	}
268  
269  	return 0;
270  }
271  
272  /**
273   * memblock_find_in_range_node - find free area in given range and node
274   * @size: size of free area to find
275   * @align: alignment of free area to find
276   * @start: start of candidate range
277   * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
278   *       %MEMBLOCK_ALLOC_ACCESSIBLE
279   * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
280   * @flags: pick from blocks based on memory attributes
281   *
282   * Find @size free area aligned to @align in the specified range and node.
283   *
284   * Return:
285   * Found address on success, 0 on failure.
286   */
287  static phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t size,
288  					phys_addr_t align, phys_addr_t start,
289  					phys_addr_t end, int nid,
290  					enum memblock_flags flags)
291  {
292  	/* pump up @end */
293  	if (end == MEMBLOCK_ALLOC_ACCESSIBLE ||
294  	    end == MEMBLOCK_ALLOC_NOLEAKTRACE)
295  		end = memblock.current_limit;
296  
297  	/* avoid allocating the first page */
298  	start = max_t(phys_addr_t, start, PAGE_SIZE);
299  	end = max(start, end);
300  
301  	if (memblock_bottom_up())
302  		return __memblock_find_range_bottom_up(start, end, size, align,
303  						       nid, flags);
304  	else
305  		return __memblock_find_range_top_down(start, end, size, align,
306  						      nid, flags);
307  }
308  
309  /**
310   * memblock_find_in_range - find free area in given range
311   * @start: start of candidate range
312   * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
313   *       %MEMBLOCK_ALLOC_ACCESSIBLE
314   * @size: size of free area to find
315   * @align: alignment of free area to find
316   *
317   * Find @size free area aligned to @align in the specified range.
318   *
319   * Return:
320   * Found address on success, 0 on failure.
321   */
322  static phys_addr_t __init_memblock memblock_find_in_range(phys_addr_t start,
323  					phys_addr_t end, phys_addr_t size,
324  					phys_addr_t align)
325  {
326  	phys_addr_t ret;
327  	enum memblock_flags flags = choose_memblock_flags();
328  
329  again:
330  	ret = memblock_find_in_range_node(size, align, start, end,
331  					    NUMA_NO_NODE, flags);
332  
333  	if (!ret && (flags & MEMBLOCK_MIRROR)) {
334  		pr_warn_ratelimited("Could not allocate %pap bytes of mirrored memory\n",
335  			&size);
336  		flags &= ~MEMBLOCK_MIRROR;
337  		goto again;
338  	}
339  
340  	return ret;
341  }
342  
343  static void __init_memblock memblock_remove_region(struct memblock_type *type, unsigned long r)
344  {
345  	type->total_size -= type->regions[r].size;
346  	memmove(&type->regions[r], &type->regions[r + 1],
347  		(type->cnt - (r + 1)) * sizeof(type->regions[r]));
348  	type->cnt--;
349  
350  	/* Special case for empty arrays */
351  	if (type->cnt == 0) {
352  		WARN_ON(type->total_size != 0);
353  		type->cnt = 1;
354  		type->regions[0].base = 0;
355  		type->regions[0].size = 0;
356  		type->regions[0].flags = 0;
357  		memblock_set_region_node(&type->regions[0], MAX_NUMNODES);
358  	}
359  }
360  
361  #ifndef CONFIG_ARCH_KEEP_MEMBLOCK
362  /**
363   * memblock_discard - discard memory and reserved arrays if they were allocated
364   */
365  void __init memblock_discard(void)
366  {
367  	phys_addr_t addr, size;
368  
369  	if (memblock.reserved.regions != memblock_reserved_init_regions) {
370  		addr = __pa(memblock.reserved.regions);
371  		size = PAGE_ALIGN(sizeof(struct memblock_region) *
372  				  memblock.reserved.max);
373  		if (memblock_reserved_in_slab)
374  			kfree(memblock.reserved.regions);
375  		else
376  			memblock_free_late(addr, size);
377  	}
378  
379  	if (memblock.memory.regions != memblock_memory_init_regions) {
380  		addr = __pa(memblock.memory.regions);
381  		size = PAGE_ALIGN(sizeof(struct memblock_region) *
382  				  memblock.memory.max);
383  		if (memblock_memory_in_slab)
384  			kfree(memblock.memory.regions);
385  		else
386  			memblock_free_late(addr, size);
387  	}
388  
389  	memblock_memory = NULL;
390  }
391  #endif
392  
393  /**
394   * memblock_double_array - double the size of the memblock regions array
395   * @type: memblock type of the regions array being doubled
396   * @new_area_start: starting address of memory range to avoid overlap with
397   * @new_area_size: size of memory range to avoid overlap with
398   *
399   * Double the size of the @type regions array. If memblock is being used to
400   * allocate memory for a new reserved regions array and there is a previously
401   * allocated memory range [@new_area_start, @new_area_start + @new_area_size]
402   * waiting to be reserved, ensure the memory used by the new array does
403   * not overlap.
404   *
405   * Return:
406   * 0 on success, -1 on failure.
407   */
408  static int __init_memblock memblock_double_array(struct memblock_type *type,
409  						phys_addr_t new_area_start,
410  						phys_addr_t new_area_size)
411  {
412  	struct memblock_region *new_array, *old_array;
413  	phys_addr_t old_alloc_size, new_alloc_size;
414  	phys_addr_t old_size, new_size, addr, new_end;
415  	int use_slab = slab_is_available();
416  	int *in_slab;
417  
418  	/* We don't allow resizing until we know about the reserved regions
419  	 * of memory that aren't suitable for allocation
420  	 */
421  	if (!memblock_can_resize)
422  		return -1;
423  
424  	/* Calculate new doubled size */
425  	old_size = type->max * sizeof(struct memblock_region);
426  	new_size = old_size << 1;
427  	/*
428  	 * We need to allocated new one align to PAGE_SIZE,
429  	 *   so we can free them completely later.
430  	 */
431  	old_alloc_size = PAGE_ALIGN(old_size);
432  	new_alloc_size = PAGE_ALIGN(new_size);
433  
434  	/* Retrieve the slab flag */
435  	if (type == &memblock.memory)
436  		in_slab = &memblock_memory_in_slab;
437  	else
438  		in_slab = &memblock_reserved_in_slab;
439  
440  	/* Try to find some space for it */
441  	if (use_slab) {
442  		new_array = kmalloc(new_size, GFP_KERNEL);
443  		addr = new_array ? __pa(new_array) : 0;
444  	} else {
445  		/* only exclude range when trying to double reserved.regions */
446  		if (type != &memblock.reserved)
447  			new_area_start = new_area_size = 0;
448  
449  		addr = memblock_find_in_range(new_area_start + new_area_size,
450  						memblock.current_limit,
451  						new_alloc_size, PAGE_SIZE);
452  		if (!addr && new_area_size)
453  			addr = memblock_find_in_range(0,
454  				min(new_area_start, memblock.current_limit),
455  				new_alloc_size, PAGE_SIZE);
456  
457  		new_array = addr ? __va(addr) : NULL;
458  	}
459  	if (!addr) {
460  		pr_err("memblock: Failed to double %s array from %ld to %ld entries !\n",
461  		       type->name, type->max, type->max * 2);
462  		return -1;
463  	}
464  
465  	new_end = addr + new_size - 1;
466  	memblock_dbg("memblock: %s is doubled to %ld at [%pa-%pa]",
467  			type->name, type->max * 2, &addr, &new_end);
468  
469  	/*
470  	 * Found space, we now need to move the array over before we add the
471  	 * reserved region since it may be our reserved array itself that is
472  	 * full.
473  	 */
474  	memcpy(new_array, type->regions, old_size);
475  	memset(new_array + type->max, 0, old_size);
476  	old_array = type->regions;
477  	type->regions = new_array;
478  	type->max <<= 1;
479  
480  	/* Free old array. We needn't free it if the array is the static one */
481  	if (*in_slab)
482  		kfree(old_array);
483  	else if (old_array != memblock_memory_init_regions &&
484  		 old_array != memblock_reserved_init_regions)
485  		memblock_free(old_array, old_alloc_size);
486  
487  	/*
488  	 * Reserve the new array if that comes from the memblock.  Otherwise, we
489  	 * needn't do it
490  	 */
491  	if (!use_slab)
492  		BUG_ON(memblock_reserve(addr, new_alloc_size));
493  
494  	/* Update slab flag */
495  	*in_slab = use_slab;
496  
497  	return 0;
498  }
499  
500  /**
501   * memblock_merge_regions - merge neighboring compatible regions
502   * @type: memblock type to scan
503   *
504   * Scan @type and merge neighboring compatible regions.
505   */
506  static void __init_memblock memblock_merge_regions(struct memblock_type *type)
507  {
508  	int i = 0;
509  
510  	/* cnt never goes below 1 */
511  	while (i < type->cnt - 1) {
512  		struct memblock_region *this = &type->regions[i];
513  		struct memblock_region *next = &type->regions[i + 1];
514  
515  		if (this->base + this->size != next->base ||
516  		    memblock_get_region_node(this) !=
517  		    memblock_get_region_node(next) ||
518  		    this->flags != next->flags) {
519  			BUG_ON(this->base + this->size > next->base);
520  			i++;
521  			continue;
522  		}
523  
524  		this->size += next->size;
525  		/* move forward from next + 1, index of which is i + 2 */
526  		memmove(next, next + 1, (type->cnt - (i + 2)) * sizeof(*next));
527  		type->cnt--;
528  	}
529  }
530  
531  /**
532   * memblock_insert_region - insert new memblock region
533   * @type:	memblock type to insert into
534   * @idx:	index for the insertion point
535   * @base:	base address of the new region
536   * @size:	size of the new region
537   * @nid:	node id of the new region
538   * @flags:	flags of the new region
539   *
540   * Insert new memblock region [@base, @base + @size) into @type at @idx.
541   * @type must already have extra room to accommodate the new region.
542   */
543  static void __init_memblock memblock_insert_region(struct memblock_type *type,
544  						   int idx, phys_addr_t base,
545  						   phys_addr_t size,
546  						   int nid,
547  						   enum memblock_flags flags)
548  {
549  	struct memblock_region *rgn = &type->regions[idx];
550  
551  	BUG_ON(type->cnt >= type->max);
552  	memmove(rgn + 1, rgn, (type->cnt - idx) * sizeof(*rgn));
553  	rgn->base = base;
554  	rgn->size = size;
555  	rgn->flags = flags;
556  	memblock_set_region_node(rgn, nid);
557  	type->cnt++;
558  	type->total_size += size;
559  }
560  
561  /**
562   * memblock_add_range - add new memblock region
563   * @type: memblock type to add new region into
564   * @base: base address of the new region
565   * @size: size of the new region
566   * @nid: nid of the new region
567   * @flags: flags of the new region
568   *
569   * Add new memblock region [@base, @base + @size) into @type.  The new region
570   * is allowed to overlap with existing ones - overlaps don't affect already
571   * existing regions.  @type is guaranteed to be minimal (all neighbouring
572   * compatible regions are merged) after the addition.
573   *
574   * Return:
575   * 0 on success, -errno on failure.
576   */
577  static int __init_memblock memblock_add_range(struct memblock_type *type,
578  				phys_addr_t base, phys_addr_t size,
579  				int nid, enum memblock_flags flags)
580  {
581  	bool insert = false;
582  	phys_addr_t obase = base;
583  	phys_addr_t end = base + memblock_cap_size(base, &size);
584  	int idx, nr_new;
585  	struct memblock_region *rgn;
586  
587  	if (!size)
588  		return 0;
589  
590  	/* special case for empty array */
591  	if (type->regions[0].size == 0) {
592  		WARN_ON(type->cnt != 1 || type->total_size);
593  		type->regions[0].base = base;
594  		type->regions[0].size = size;
595  		type->regions[0].flags = flags;
596  		memblock_set_region_node(&type->regions[0], nid);
597  		type->total_size = size;
598  		return 0;
599  	}
600  
601  	/*
602  	 * The worst case is when new range overlaps all existing regions,
603  	 * then we'll need type->cnt + 1 empty regions in @type. So if
604  	 * type->cnt * 2 + 1 is less than type->max, we know
605  	 * that there is enough empty regions in @type, and we can insert
606  	 * regions directly.
607  	 */
608  	if (type->cnt * 2 + 1 < type->max)
609  		insert = true;
610  
611  repeat:
612  	/*
613  	 * The following is executed twice.  Once with %false @insert and
614  	 * then with %true.  The first counts the number of regions needed
615  	 * to accommodate the new area.  The second actually inserts them.
616  	 */
617  	base = obase;
618  	nr_new = 0;
619  
620  	for_each_memblock_type(idx, type, rgn) {
621  		phys_addr_t rbase = rgn->base;
622  		phys_addr_t rend = rbase + rgn->size;
623  
624  		if (rbase >= end)
625  			break;
626  		if (rend <= base)
627  			continue;
628  		/*
629  		 * @rgn overlaps.  If it separates the lower part of new
630  		 * area, insert that portion.
631  		 */
632  		if (rbase > base) {
633  #ifdef CONFIG_NUMA
634  			WARN_ON(nid != memblock_get_region_node(rgn));
635  #endif
636  			WARN_ON(flags != rgn->flags);
637  			nr_new++;
638  			if (insert)
639  				memblock_insert_region(type, idx++, base,
640  						       rbase - base, nid,
641  						       flags);
642  		}
643  		/* area below @rend is dealt with, forget about it */
644  		base = min(rend, end);
645  	}
646  
647  	/* insert the remaining portion */
648  	if (base < end) {
649  		nr_new++;
650  		if (insert)
651  			memblock_insert_region(type, idx, base, end - base,
652  					       nid, flags);
653  	}
654  
655  	if (!nr_new)
656  		return 0;
657  
658  	/*
659  	 * If this was the first round, resize array and repeat for actual
660  	 * insertions; otherwise, merge and return.
661  	 */
662  	if (!insert) {
663  		while (type->cnt + nr_new > type->max)
664  			if (memblock_double_array(type, obase, size) < 0)
665  				return -ENOMEM;
666  		insert = true;
667  		goto repeat;
668  	} else {
669  		memblock_merge_regions(type);
670  		return 0;
671  	}
672  }
673  
674  /**
675   * memblock_add_node - add new memblock region within a NUMA node
676   * @base: base address of the new region
677   * @size: size of the new region
678   * @nid: nid of the new region
679   * @flags: flags of the new region
680   *
681   * Add new memblock region [@base, @base + @size) to the "memory"
682   * type. See memblock_add_range() description for mode details
683   *
684   * Return:
685   * 0 on success, -errno on failure.
686   */
687  int __init_memblock memblock_add_node(phys_addr_t base, phys_addr_t size,
688  				      int nid, enum memblock_flags flags)
689  {
690  	phys_addr_t end = base + size - 1;
691  
692  	memblock_dbg("%s: [%pa-%pa] nid=%d flags=%x %pS\n", __func__,
693  		     &base, &end, nid, flags, (void *)_RET_IP_);
694  
695  	return memblock_add_range(&memblock.memory, base, size, nid, flags);
696  }
697  
698  /**
699   * memblock_add - add new memblock region
700   * @base: base address of the new region
701   * @size: size of the new region
702   *
703   * Add new memblock region [@base, @base + @size) to the "memory"
704   * type. See memblock_add_range() description for mode details
705   *
706   * Return:
707   * 0 on success, -errno on failure.
708   */
709  int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
710  {
711  	phys_addr_t end = base + size - 1;
712  
713  	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
714  		     &base, &end, (void *)_RET_IP_);
715  
716  	return memblock_add_range(&memblock.memory, base, size, MAX_NUMNODES, 0);
717  }
718  
719  /**
720   * memblock_isolate_range - isolate given range into disjoint memblocks
721   * @type: memblock type to isolate range for
722   * @base: base of range to isolate
723   * @size: size of range to isolate
724   * @start_rgn: out parameter for the start of isolated region
725   * @end_rgn: out parameter for the end of isolated region
726   *
727   * Walk @type and ensure that regions don't cross the boundaries defined by
728   * [@base, @base + @size).  Crossing regions are split at the boundaries,
729   * which may create at most two more regions.  The index of the first
730   * region inside the range is returned in *@start_rgn and end in *@end_rgn.
731   *
732   * Return:
733   * 0 on success, -errno on failure.
734   */
735  static int __init_memblock memblock_isolate_range(struct memblock_type *type,
736  					phys_addr_t base, phys_addr_t size,
737  					int *start_rgn, int *end_rgn)
738  {
739  	phys_addr_t end = base + memblock_cap_size(base, &size);
740  	int idx;
741  	struct memblock_region *rgn;
742  
743  	*start_rgn = *end_rgn = 0;
744  
745  	if (!size)
746  		return 0;
747  
748  	/* we'll create at most two more regions */
749  	while (type->cnt + 2 > type->max)
750  		if (memblock_double_array(type, base, size) < 0)
751  			return -ENOMEM;
752  
753  	for_each_memblock_type(idx, type, rgn) {
754  		phys_addr_t rbase = rgn->base;
755  		phys_addr_t rend = rbase + rgn->size;
756  
757  		if (rbase >= end)
758  			break;
759  		if (rend <= base)
760  			continue;
761  
762  		if (rbase < base) {
763  			/*
764  			 * @rgn intersects from below.  Split and continue
765  			 * to process the next region - the new top half.
766  			 */
767  			rgn->base = base;
768  			rgn->size -= base - rbase;
769  			type->total_size -= base - rbase;
770  			memblock_insert_region(type, idx, rbase, base - rbase,
771  					       memblock_get_region_node(rgn),
772  					       rgn->flags);
773  		} else if (rend > end) {
774  			/*
775  			 * @rgn intersects from above.  Split and redo the
776  			 * current region - the new bottom half.
777  			 */
778  			rgn->base = end;
779  			rgn->size -= end - rbase;
780  			type->total_size -= end - rbase;
781  			memblock_insert_region(type, idx--, rbase, end - rbase,
782  					       memblock_get_region_node(rgn),
783  					       rgn->flags);
784  		} else {
785  			/* @rgn is fully contained, record it */
786  			if (!*end_rgn)
787  				*start_rgn = idx;
788  			*end_rgn = idx + 1;
789  		}
790  	}
791  
792  	return 0;
793  }
794  
795  static int __init_memblock memblock_remove_range(struct memblock_type *type,
796  					  phys_addr_t base, phys_addr_t size)
797  {
798  	int start_rgn, end_rgn;
799  	int i, ret;
800  
801  	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
802  	if (ret)
803  		return ret;
804  
805  	for (i = end_rgn - 1; i >= start_rgn; i--)
806  		memblock_remove_region(type, i);
807  	return 0;
808  }
809  
810  int __init_memblock memblock_remove(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_remove_range(&memblock.memory, base, size);
818  }
819  
820  /**
821   * memblock_free - free boot memory allocation
822   * @ptr: starting address of the  boot memory allocation
823   * @size: size of the boot memory block in bytes
824   *
825   * Free boot memory block previously allocated by memblock_alloc_xx() API.
826   * The freeing memory will not be released to the buddy allocator.
827   */
828  void __init_memblock memblock_free(void *ptr, size_t size)
829  {
830  	if (ptr)
831  		memblock_phys_free(__pa(ptr), size);
832  }
833  
834  /**
835   * memblock_phys_free - free boot memory block
836   * @base: phys starting address of the  boot memory block
837   * @size: size of the boot memory block in bytes
838   *
839   * Free boot memory block previously allocated by memblock_alloc_xx() API.
840   * The freeing memory will not be released to the buddy allocator.
841   */
842  int __init_memblock memblock_phys_free(phys_addr_t base, phys_addr_t size)
843  {
844  	phys_addr_t end = base + size - 1;
845  
846  	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
847  		     &base, &end, (void *)_RET_IP_);
848  
849  	kmemleak_free_part_phys(base, size);
850  	return memblock_remove_range(&memblock.reserved, base, size);
851  }
852  
853  int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
854  {
855  	phys_addr_t end = base + size - 1;
856  
857  	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
858  		     &base, &end, (void *)_RET_IP_);
859  
860  	return memblock_add_range(&memblock.reserved, base, size, MAX_NUMNODES, 0);
861  }
862  
863  #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
864  int __init_memblock memblock_physmem_add(phys_addr_t base, phys_addr_t size)
865  {
866  	phys_addr_t end = base + size - 1;
867  
868  	memblock_dbg("%s: [%pa-%pa] %pS\n", __func__,
869  		     &base, &end, (void *)_RET_IP_);
870  
871  	return memblock_add_range(&physmem, base, size, MAX_NUMNODES, 0);
872  }
873  #endif
874  
875  /**
876   * memblock_setclr_flag - set or clear flag for a memory region
877   * @base: base address of the region
878   * @size: size of the region
879   * @set: set or clear the flag
880   * @flag: the flag to update
881   *
882   * This function isolates region [@base, @base + @size), and sets/clears flag
883   *
884   * Return: 0 on success, -errno on failure.
885   */
886  static int __init_memblock memblock_setclr_flag(phys_addr_t base,
887  				phys_addr_t size, int set, int flag)
888  {
889  	struct memblock_type *type = &memblock.memory;
890  	int i, ret, start_rgn, end_rgn;
891  
892  	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
893  	if (ret)
894  		return ret;
895  
896  	for (i = start_rgn; i < end_rgn; i++) {
897  		struct memblock_region *r = &type->regions[i];
898  
899  		if (set)
900  			r->flags |= flag;
901  		else
902  			r->flags &= ~flag;
903  	}
904  
905  	memblock_merge_regions(type);
906  	return 0;
907  }
908  
909  /**
910   * memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
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_hotplug(phys_addr_t base, phys_addr_t size)
917  {
918  	return memblock_setclr_flag(base, size, 1, MEMBLOCK_HOTPLUG);
919  }
920  
921  /**
922   * memblock_clear_hotplug - Clear flag MEMBLOCK_HOTPLUG 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_hotplug(phys_addr_t base, phys_addr_t size)
929  {
930  	return memblock_setclr_flag(base, size, 0, MEMBLOCK_HOTPLUG);
931  }
932  
933  /**
934   * memblock_mark_mirror - Mark mirrored memory with flag MEMBLOCK_MIRROR.
935   * @base: the base phys addr of the region
936   * @size: the size of the region
937   *
938   * Return: 0 on success, -errno on failure.
939   */
940  int __init_memblock memblock_mark_mirror(phys_addr_t base, phys_addr_t size)
941  {
942  	if (!mirrored_kernelcore)
943  		return 0;
944  
945  	system_has_some_mirror = true;
946  
947  	return memblock_setclr_flag(base, size, 1, MEMBLOCK_MIRROR);
948  }
949  
950  /**
951   * memblock_mark_nomap - Mark a memory region with flag MEMBLOCK_NOMAP.
952   * @base: the base phys addr of the region
953   * @size: the size of the region
954   *
955   * The memory regions marked with %MEMBLOCK_NOMAP will not be added to the
956   * direct mapping of the physical memory. These regions will still be
957   * covered by the memory map. The struct page representing NOMAP memory
958   * frames in the memory map will be PageReserved()
959   *
960   * Note: if the memory being marked %MEMBLOCK_NOMAP was allocated from
961   * memblock, the caller must inform kmemleak to ignore that memory
962   *
963   * Return: 0 on success, -errno on failure.
964   */
965  int __init_memblock memblock_mark_nomap(phys_addr_t base, phys_addr_t size)
966  {
967  	return memblock_setclr_flag(base, size, 1, MEMBLOCK_NOMAP);
968  }
969  
970  /**
971   * memblock_clear_nomap - Clear flag MEMBLOCK_NOMAP for a specified region.
972   * @base: the base phys addr of the region
973   * @size: the size of the region
974   *
975   * Return: 0 on success, -errno on failure.
976   */
977  int __init_memblock memblock_clear_nomap(phys_addr_t base, phys_addr_t size)
978  {
979  	return memblock_setclr_flag(base, size, 0, MEMBLOCK_NOMAP);
980  }
981  
982  static bool should_skip_region(struct memblock_type *type,
983  			       struct memblock_region *m,
984  			       int nid, int flags)
985  {
986  	int m_nid = memblock_get_region_node(m);
987  
988  	/* we never skip regions when iterating memblock.reserved or physmem */
989  	if (type != memblock_memory)
990  		return false;
991  
992  	/* only memory regions are associated with nodes, check it */
993  	if (nid != NUMA_NO_NODE && nid != m_nid)
994  		return true;
995  
996  	/* skip hotpluggable memory regions if needed */
997  	if (movable_node_is_enabled() && memblock_is_hotpluggable(m) &&
998  	    !(flags & MEMBLOCK_HOTPLUG))
999  		return true;
1000  
1001  	/* if we want mirror memory skip non-mirror memory regions */
1002  	if ((flags & MEMBLOCK_MIRROR) && !memblock_is_mirror(m))
1003  		return true;
1004  
1005  	/* skip nomap memory unless we were asked for it explicitly */
1006  	if (!(flags & MEMBLOCK_NOMAP) && memblock_is_nomap(m))
1007  		return true;
1008  
1009  	/* skip driver-managed memory unless we were asked for it explicitly */
1010  	if (!(flags & MEMBLOCK_DRIVER_MANAGED) && memblock_is_driver_managed(m))
1011  		return true;
1012  
1013  	return false;
1014  }
1015  
1016  /**
1017   * __next_mem_range - next function for for_each_free_mem_range() etc.
1018   * @idx: pointer to u64 loop variable
1019   * @nid: node selector, %NUMA_NO_NODE for all nodes
1020   * @flags: pick from blocks based on memory attributes
1021   * @type_a: pointer to memblock_type from where the range is taken
1022   * @type_b: pointer to memblock_type which excludes memory from being taken
1023   * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
1024   * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
1025   * @out_nid: ptr to int for nid of the range, can be %NULL
1026   *
1027   * Find the first area from *@idx which matches @nid, fill the out
1028   * parameters, and update *@idx for the next iteration.  The lower 32bit of
1029   * *@idx contains index into type_a and the upper 32bit indexes the
1030   * areas before each region in type_b.	For example, if type_b regions
1031   * look like the following,
1032   *
1033   *	0:[0-16), 1:[32-48), 2:[128-130)
1034   *
1035   * The upper 32bit indexes the following regions.
1036   *
1037   *	0:[0-0), 1:[16-32), 2:[48-128), 3:[130-MAX)
1038   *
1039   * As both region arrays are sorted, the function advances the two indices
1040   * in lockstep and returns each intersection.
1041   */
1042  void __next_mem_range(u64 *idx, int nid, enum memblock_flags flags,
1043  		      struct memblock_type *type_a,
1044  		      struct memblock_type *type_b, phys_addr_t *out_start,
1045  		      phys_addr_t *out_end, int *out_nid)
1046  {
1047  	int idx_a = *idx & 0xffffffff;
1048  	int idx_b = *idx >> 32;
1049  
1050  	if (WARN_ONCE(nid == MAX_NUMNODES,
1051  	"Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
1052  		nid = NUMA_NO_NODE;
1053  
1054  	for (; idx_a < type_a->cnt; idx_a++) {
1055  		struct memblock_region *m = &type_a->regions[idx_a];
1056  
1057  		phys_addr_t m_start = m->base;
1058  		phys_addr_t m_end = m->base + m->size;
1059  		int	    m_nid = memblock_get_region_node(m);
1060  
1061  		if (should_skip_region(type_a, m, nid, flags))
1062  			continue;
1063  
1064  		if (!type_b) {
1065  			if (out_start)
1066  				*out_start = m_start;
1067  			if (out_end)
1068  				*out_end = m_end;
1069  			if (out_nid)
1070  				*out_nid = m_nid;
1071  			idx_a++;
1072  			*idx = (u32)idx_a | (u64)idx_b << 32;
1073  			return;
1074  		}
1075  
1076  		/* scan areas before each reservation */
1077  		for (; idx_b < type_b->cnt + 1; idx_b++) {
1078  			struct memblock_region *r;
1079  			phys_addr_t r_start;
1080  			phys_addr_t r_end;
1081  
1082  			r = &type_b->regions[idx_b];
1083  			r_start = idx_b ? r[-1].base + r[-1].size : 0;
1084  			r_end = idx_b < type_b->cnt ?
1085  				r->base : PHYS_ADDR_MAX;
1086  
1087  			/*
1088  			 * if idx_b advanced past idx_a,
1089  			 * break out to advance idx_a
1090  			 */
1091  			if (r_start >= m_end)
1092  				break;
1093  			/* if the two regions intersect, we're done */
1094  			if (m_start < r_end) {
1095  				if (out_start)
1096  					*out_start =
1097  						max(m_start, r_start);
1098  				if (out_end)
1099  					*out_end = min(m_end, r_end);
1100  				if (out_nid)
1101  					*out_nid = m_nid;
1102  				/*
1103  				 * The region which ends first is
1104  				 * advanced for the next iteration.
1105  				 */
1106  				if (m_end <= r_end)
1107  					idx_a++;
1108  				else
1109  					idx_b++;
1110  				*idx = (u32)idx_a | (u64)idx_b << 32;
1111  				return;
1112  			}
1113  		}
1114  	}
1115  
1116  	/* signal end of iteration */
1117  	*idx = ULLONG_MAX;
1118  }
1119  
1120  /**
1121   * __next_mem_range_rev - generic next function for for_each_*_range_rev()
1122   *
1123   * @idx: pointer to u64 loop variable
1124   * @nid: node selector, %NUMA_NO_NODE for all nodes
1125   * @flags: pick from blocks based on memory attributes
1126   * @type_a: pointer to memblock_type from where the range is taken
1127   * @type_b: pointer to memblock_type which excludes memory from being taken
1128   * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
1129   * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
1130   * @out_nid: ptr to int for nid of the range, can be %NULL
1131   *
1132   * Finds the next range from type_a which is not marked as unsuitable
1133   * in type_b.
1134   *
1135   * Reverse of __next_mem_range().
1136   */
1137  void __init_memblock __next_mem_range_rev(u64 *idx, int nid,
1138  					  enum memblock_flags flags,
1139  					  struct memblock_type *type_a,
1140  					  struct memblock_type *type_b,
1141  					  phys_addr_t *out_start,
1142  					  phys_addr_t *out_end, int *out_nid)
1143  {
1144  	int idx_a = *idx & 0xffffffff;
1145  	int idx_b = *idx >> 32;
1146  
1147  	if (WARN_ONCE(nid == MAX_NUMNODES, "Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
1148  		nid = NUMA_NO_NODE;
1149  
1150  	if (*idx == (u64)ULLONG_MAX) {
1151  		idx_a = type_a->cnt - 1;
1152  		if (type_b != NULL)
1153  			idx_b = type_b->cnt;
1154  		else
1155  			idx_b = 0;
1156  	}
1157  
1158  	for (; idx_a >= 0; idx_a--) {
1159  		struct memblock_region *m = &type_a->regions[idx_a];
1160  
1161  		phys_addr_t m_start = m->base;
1162  		phys_addr_t m_end = m->base + m->size;
1163  		int m_nid = memblock_get_region_node(m);
1164  
1165  		if (should_skip_region(type_a, m, nid, flags))
1166  			continue;
1167  
1168  		if (!type_b) {
1169  			if (out_start)
1170  				*out_start = m_start;
1171  			if (out_end)
1172  				*out_end = m_end;
1173  			if (out_nid)
1174  				*out_nid = m_nid;
1175  			idx_a--;
1176  			*idx = (u32)idx_a | (u64)idx_b << 32;
1177  			return;
1178  		}
1179  
1180  		/* scan areas before each reservation */
1181  		for (; idx_b >= 0; idx_b--) {
1182  			struct memblock_region *r;
1183  			phys_addr_t r_start;
1184  			phys_addr_t r_end;
1185  
1186  			r = &type_b->regions[idx_b];
1187  			r_start = idx_b ? r[-1].base + r[-1].size : 0;
1188  			r_end = idx_b < type_b->cnt ?
1189  				r->base : PHYS_ADDR_MAX;
1190  			/*
1191  			 * if idx_b advanced past idx_a,
1192  			 * break out to advance idx_a
1193  			 */
1194  
1195  			if (r_end <= m_start)
1196  				break;
1197  			/* if the two regions intersect, we're done */
1198  			if (m_end > r_start) {
1199  				if (out_start)
1200  					*out_start = max(m_start, r_start);
1201  				if (out_end)
1202  					*out_end = min(m_end, r_end);
1203  				if (out_nid)
1204  					*out_nid = m_nid;
1205  				if (m_start >= r_start)
1206  					idx_a--;
1207  				else
1208  					idx_b--;
1209  				*idx = (u32)idx_a | (u64)idx_b << 32;
1210  				return;
1211  			}
1212  		}
1213  	}
1214  	/* signal end of iteration */
1215  	*idx = ULLONG_MAX;
1216  }
1217  
1218  /*
1219   * Common iterator interface used to define for_each_mem_pfn_range().
1220   */
1221  void __init_memblock __next_mem_pfn_range(int *idx, int nid,
1222  				unsigned long *out_start_pfn,
1223  				unsigned long *out_end_pfn, int *out_nid)
1224  {
1225  	struct memblock_type *type = &memblock.memory;
1226  	struct memblock_region *r;
1227  	int r_nid;
1228  
1229  	while (++*idx < type->cnt) {
1230  		r = &type->regions[*idx];
1231  		r_nid = memblock_get_region_node(r);
1232  
1233  		if (PFN_UP(r->base) >= PFN_DOWN(r->base + r->size))
1234  			continue;
1235  		if (nid == MAX_NUMNODES || nid == r_nid)
1236  			break;
1237  	}
1238  	if (*idx >= type->cnt) {
1239  		*idx = -1;
1240  		return;
1241  	}
1242  
1243  	if (out_start_pfn)
1244  		*out_start_pfn = PFN_UP(r->base);
1245  	if (out_end_pfn)
1246  		*out_end_pfn = PFN_DOWN(r->base + r->size);
1247  	if (out_nid)
1248  		*out_nid = r_nid;
1249  }
1250  
1251  /**
1252   * memblock_set_node - set node ID on memblock regions
1253   * @base: base of area to set node ID for
1254   * @size: size of area to set node ID for
1255   * @type: memblock type to set node ID for
1256   * @nid: node ID to set
1257   *
1258   * Set the nid of memblock @type regions in [@base, @base + @size) to @nid.
1259   * Regions which cross the area boundaries are split as necessary.
1260   *
1261   * Return:
1262   * 0 on success, -errno on failure.
1263   */
1264  int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
1265  				      struct memblock_type *type, int nid)
1266  {
1267  #ifdef CONFIG_NUMA
1268  	int start_rgn, end_rgn;
1269  	int i, ret;
1270  
1271  	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
1272  	if (ret)
1273  		return ret;
1274  
1275  	for (i = start_rgn; i < end_rgn; i++)
1276  		memblock_set_region_node(&type->regions[i], nid);
1277  
1278  	memblock_merge_regions(type);
1279  #endif
1280  	return 0;
1281  }
1282  
1283  #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
1284  /**
1285   * __next_mem_pfn_range_in_zone - iterator for for_each_*_range_in_zone()
1286   *
1287   * @idx: pointer to u64 loop variable
1288   * @zone: zone in which all of the memory blocks reside
1289   * @out_spfn: ptr to ulong for start pfn of the range, can be %NULL
1290   * @out_epfn: ptr to ulong for end pfn of the range, can be %NULL
1291   *
1292   * This function is meant to be a zone/pfn specific wrapper for the
1293   * for_each_mem_range type iterators. Specifically they are used in the
1294   * deferred memory init routines and as such we were duplicating much of
1295   * this logic throughout the code. So instead of having it in multiple
1296   * locations it seemed like it would make more sense to centralize this to
1297   * one new iterator that does everything they need.
1298   */
1299  void __init_memblock
1300  __next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone,
1301  			     unsigned long *out_spfn, unsigned long *out_epfn)
1302  {
1303  	int zone_nid = zone_to_nid(zone);
1304  	phys_addr_t spa, epa;
1305  
1306  	__next_mem_range(idx, zone_nid, MEMBLOCK_NONE,
1307  			 &memblock.memory, &memblock.reserved,
1308  			 &spa, &epa, NULL);
1309  
1310  	while (*idx != U64_MAX) {
1311  		unsigned long epfn = PFN_DOWN(epa);
1312  		unsigned long spfn = PFN_UP(spa);
1313  
1314  		/*
1315  		 * Verify the end is at least past the start of the zone and
1316  		 * that we have at least one PFN to initialize.
1317  		 */
1318  		if (zone->zone_start_pfn < epfn && spfn < epfn) {
1319  			/* if we went too far just stop searching */
1320  			if (zone_end_pfn(zone) <= spfn) {
1321  				*idx = U64_MAX;
1322  				break;
1323  			}
1324  
1325  			if (out_spfn)
1326  				*out_spfn = max(zone->zone_start_pfn, spfn);
1327  			if (out_epfn)
1328  				*out_epfn = min(zone_end_pfn(zone), epfn);
1329  
1330  			return;
1331  		}
1332  
1333  		__next_mem_range(idx, zone_nid, MEMBLOCK_NONE,
1334  				 &memblock.memory, &memblock.reserved,
1335  				 &spa, &epa, NULL);
1336  	}
1337  
1338  	/* signal end of iteration */
1339  	if (out_spfn)
1340  		*out_spfn = ULONG_MAX;
1341  	if (out_epfn)
1342  		*out_epfn = 0;
1343  }
1344  
1345  #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
1346  
1347  /**
1348   * memblock_alloc_range_nid - allocate boot memory block
1349   * @size: size of memory block to be allocated in bytes
1350   * @align: alignment of the region and block's size
1351   * @start: the lower bound of the memory region to allocate (phys address)
1352   * @end: the upper bound of the memory region to allocate (phys address)
1353   * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1354   * @exact_nid: control the allocation fall back to other nodes
1355   *
1356   * The allocation is performed from memory region limited by
1357   * memblock.current_limit if @end == %MEMBLOCK_ALLOC_ACCESSIBLE.
1358   *
1359   * If the specified node can not hold the requested memory and @exact_nid
1360   * is false, the allocation falls back to any node in the system.
1361   *
1362   * For systems with memory mirroring, the allocation is attempted first
1363   * from the regions with mirroring enabled and then retried from any
1364   * memory region.
1365   *
1366   * In addition, function using kmemleak_alloc_phys for allocated boot
1367   * memory block, it is never reported as leaks.
1368   *
1369   * Return:
1370   * Physical address of allocated memory block on success, %0 on failure.
1371   */
1372  phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size,
1373  					phys_addr_t align, phys_addr_t start,
1374  					phys_addr_t end, int nid,
1375  					bool exact_nid)
1376  {
1377  	enum memblock_flags flags = choose_memblock_flags();
1378  	phys_addr_t found;
1379  
1380  	if (WARN_ONCE(nid == MAX_NUMNODES, "Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
1381  		nid = NUMA_NO_NODE;
1382  
1383  	if (!align) {
1384  		/* Can't use WARNs this early in boot on powerpc */
1385  		dump_stack();
1386  		align = SMP_CACHE_BYTES;
1387  	}
1388  
1389  again:
1390  	found = memblock_find_in_range_node(size, align, start, end, nid,
1391  					    flags);
1392  	if (found && !memblock_reserve(found, size))
1393  		goto done;
1394  
1395  	if (nid != NUMA_NO_NODE && !exact_nid) {
1396  		found = memblock_find_in_range_node(size, align, start,
1397  						    end, NUMA_NO_NODE,
1398  						    flags);
1399  		if (found && !memblock_reserve(found, size))
1400  			goto done;
1401  	}
1402  
1403  	if (flags & MEMBLOCK_MIRROR) {
1404  		flags &= ~MEMBLOCK_MIRROR;
1405  		pr_warn_ratelimited("Could not allocate %pap bytes of mirrored memory\n",
1406  			&size);
1407  		goto again;
1408  	}
1409  
1410  	return 0;
1411  
1412  done:
1413  	/*
1414  	 * Skip kmemleak for those places like kasan_init() and
1415  	 * early_pgtable_alloc() due to high volume.
1416  	 */
1417  	if (end != MEMBLOCK_ALLOC_NOLEAKTRACE)
1418  		/*
1419  		 * Memblock allocated blocks are never reported as
1420  		 * leaks. This is because many of these blocks are
1421  		 * only referred via the physical address which is
1422  		 * not looked up by kmemleak.
1423  		 */
1424  		kmemleak_alloc_phys(found, size, 0);
1425  
1426  	return found;
1427  }
1428  
1429  /**
1430   * memblock_phys_alloc_range - allocate a memory block inside specified range
1431   * @size: size of memory block to be allocated in bytes
1432   * @align: alignment of the region and block's size
1433   * @start: the lower bound of the memory region to allocate (physical address)
1434   * @end: the upper bound of the memory region to allocate (physical address)
1435   *
1436   * Allocate @size bytes in the between @start and @end.
1437   *
1438   * Return: physical address of the allocated memory block on success,
1439   * %0 on failure.
1440   */
1441  phys_addr_t __init memblock_phys_alloc_range(phys_addr_t size,
1442  					     phys_addr_t align,
1443  					     phys_addr_t start,
1444  					     phys_addr_t end)
1445  {
1446  	memblock_dbg("%s: %llu bytes align=0x%llx from=%pa max_addr=%pa %pS\n",
1447  		     __func__, (u64)size, (u64)align, &start, &end,
1448  		     (void *)_RET_IP_);
1449  	return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE,
1450  					false);
1451  }
1452  
1453  /**
1454   * memblock_phys_alloc_try_nid - allocate a memory block from specified NUMA node
1455   * @size: size of memory block to be allocated in bytes
1456   * @align: alignment of the region and block's size
1457   * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1458   *
1459   * Allocates memory block from the specified NUMA node. If the node
1460   * has no available memory, attempts to allocated from any node in the
1461   * system.
1462   *
1463   * Return: physical address of the allocated memory block on success,
1464   * %0 on failure.
1465   */
1466  phys_addr_t __init memblock_phys_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
1467  {
1468  	return memblock_alloc_range_nid(size, align, 0,
1469  					MEMBLOCK_ALLOC_ACCESSIBLE, nid, false);
1470  }
1471  
1472  /**
1473   * memblock_alloc_internal - allocate boot memory block
1474   * @size: size of memory block to be allocated in bytes
1475   * @align: alignment of the region and block's size
1476   * @min_addr: the lower bound of the memory region to allocate (phys address)
1477   * @max_addr: the upper bound of the memory region to allocate (phys address)
1478   * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1479   * @exact_nid: control the allocation fall back to other nodes
1480   *
1481   * Allocates memory block using memblock_alloc_range_nid() and
1482   * converts the returned physical address to virtual.
1483   *
1484   * The @min_addr limit is dropped if it can not be satisfied and the allocation
1485   * will fall back to memory below @min_addr. Other constraints, such
1486   * as node and mirrored memory will be handled again in
1487   * memblock_alloc_range_nid().
1488   *
1489   * Return:
1490   * Virtual address of allocated memory block on success, NULL on failure.
1491   */
1492  static void * __init memblock_alloc_internal(
1493  				phys_addr_t size, phys_addr_t align,
1494  				phys_addr_t min_addr, phys_addr_t max_addr,
1495  				int nid, bool exact_nid)
1496  {
1497  	phys_addr_t alloc;
1498  
1499  	/*
1500  	 * Detect any accidental use of these APIs after slab is ready, as at
1501  	 * this moment memblock may be deinitialized already and its
1502  	 * internal data may be destroyed (after execution of memblock_free_all)
1503  	 */
1504  	if (WARN_ON_ONCE(slab_is_available()))
1505  		return kzalloc_node(size, GFP_NOWAIT, nid);
1506  
1507  	if (max_addr > memblock.current_limit)
1508  		max_addr = memblock.current_limit;
1509  
1510  	alloc = memblock_alloc_range_nid(size, align, min_addr, max_addr, nid,
1511  					exact_nid);
1512  
1513  	/* retry allocation without lower limit */
1514  	if (!alloc && min_addr)
1515  		alloc = memblock_alloc_range_nid(size, align, 0, max_addr, nid,
1516  						exact_nid);
1517  
1518  	if (!alloc)
1519  		return NULL;
1520  
1521  	return phys_to_virt(alloc);
1522  }
1523  
1524  /**
1525   * memblock_alloc_exact_nid_raw - allocate boot memory block on the exact node
1526   * without zeroing memory
1527   * @size: size of memory block to be allocated in bytes
1528   * @align: alignment of the region and block's size
1529   * @min_addr: the lower bound of the memory region from where the allocation
1530   *	  is preferred (phys address)
1531   * @max_addr: the upper bound of the memory region from where the allocation
1532   *	      is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to
1533   *	      allocate only from memory limited by memblock.current_limit value
1534   * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1535   *
1536   * Public function, provides additional debug information (including caller
1537   * info), if enabled. Does not zero allocated memory.
1538   *
1539   * Return:
1540   * Virtual address of allocated memory block on success, NULL on failure.
1541   */
1542  void * __init memblock_alloc_exact_nid_raw(
1543  			phys_addr_t size, phys_addr_t align,
1544  			phys_addr_t min_addr, phys_addr_t max_addr,
1545  			int nid)
1546  {
1547  	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
1548  		     __func__, (u64)size, (u64)align, nid, &min_addr,
1549  		     &max_addr, (void *)_RET_IP_);
1550  
1551  	return memblock_alloc_internal(size, align, min_addr, max_addr, nid,
1552  				       true);
1553  }
1554  
1555  /**
1556   * memblock_alloc_try_nid_raw - allocate boot memory block without zeroing
1557   * memory and without panicking
1558   * @size: size of memory block to be allocated in bytes
1559   * @align: alignment of the region and block's size
1560   * @min_addr: the lower bound of the memory region from where the allocation
1561   *	  is preferred (phys address)
1562   * @max_addr: the upper bound of the memory region from where the allocation
1563   *	      is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to
1564   *	      allocate only from memory limited by memblock.current_limit value
1565   * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1566   *
1567   * Public function, provides additional debug information (including caller
1568   * info), if enabled. Does not zero allocated memory, does not panic if request
1569   * cannot be satisfied.
1570   *
1571   * Return:
1572   * Virtual address of allocated memory block on success, NULL on failure.
1573   */
1574  void * __init memblock_alloc_try_nid_raw(
1575  			phys_addr_t size, phys_addr_t align,
1576  			phys_addr_t min_addr, phys_addr_t max_addr,
1577  			int nid)
1578  {
1579  	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
1580  		     __func__, (u64)size, (u64)align, nid, &min_addr,
1581  		     &max_addr, (void *)_RET_IP_);
1582  
1583  	return memblock_alloc_internal(size, align, min_addr, max_addr, nid,
1584  				       false);
1585  }
1586  
1587  /**
1588   * memblock_alloc_try_nid - allocate boot memory block
1589   * @size: size of memory block to be allocated in bytes
1590   * @align: alignment of the region and block's size
1591   * @min_addr: the lower bound of the memory region from where the allocation
1592   *	  is preferred (phys address)
1593   * @max_addr: the upper bound of the memory region from where the allocation
1594   *	      is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to
1595   *	      allocate only from memory limited by memblock.current_limit value
1596   * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1597   *
1598   * Public function, provides additional debug information (including caller
1599   * info), if enabled. This function zeroes the allocated memory.
1600   *
1601   * Return:
1602   * Virtual address of allocated memory block on success, NULL on failure.
1603   */
1604  void * __init memblock_alloc_try_nid(
1605  			phys_addr_t size, phys_addr_t align,
1606  			phys_addr_t min_addr, phys_addr_t max_addr,
1607  			int nid)
1608  {
1609  	void *ptr;
1610  
1611  	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
1612  		     __func__, (u64)size, (u64)align, nid, &min_addr,
1613  		     &max_addr, (void *)_RET_IP_);
1614  	ptr = memblock_alloc_internal(size, align,
1615  					   min_addr, max_addr, nid, false);
1616  	if (ptr)
1617  		memset(ptr, 0, size);
1618  
1619  	return ptr;
1620  }
1621  
1622  /**
1623   * memblock_free_late - free pages directly to buddy allocator
1624   * @base: phys starting address of the  boot memory block
1625   * @size: size of the boot memory block in bytes
1626   *
1627   * This is only useful when the memblock allocator has already been torn
1628   * down, but we are still initializing the system.  Pages are released directly
1629   * to the buddy allocator.
1630   */
1631  void __init memblock_free_late(phys_addr_t base, phys_addr_t size)
1632  {
1633  	phys_addr_t cursor, end;
1634  
1635  	end = base + size - 1;
1636  	memblock_dbg("%s: [%pa-%pa] %pS\n",
1637  		     __func__, &base, &end, (void *)_RET_IP_);
1638  	kmemleak_free_part_phys(base, size);
1639  	cursor = PFN_UP(base);
1640  	end = PFN_DOWN(base + size);
1641  
1642  	for (; cursor < end; cursor++) {
1643  		memblock_free_pages(pfn_to_page(cursor), cursor, 0);
1644  		totalram_pages_inc();
1645  	}
1646  }
1647  
1648  /*
1649   * Remaining API functions
1650   */
1651  
1652  phys_addr_t __init_memblock memblock_phys_mem_size(void)
1653  {
1654  	return memblock.memory.total_size;
1655  }
1656  
1657  phys_addr_t __init_memblock memblock_reserved_size(void)
1658  {
1659  	return memblock.reserved.total_size;
1660  }
1661  
1662  /* lowest address */
1663  phys_addr_t __init_memblock memblock_start_of_DRAM(void)
1664  {
1665  	return memblock.memory.regions[0].base;
1666  }
1667  
1668  phys_addr_t __init_memblock memblock_end_of_DRAM(void)
1669  {
1670  	int idx = memblock.memory.cnt - 1;
1671  
1672  	return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
1673  }
1674  
1675  static phys_addr_t __init_memblock __find_max_addr(phys_addr_t limit)
1676  {
1677  	phys_addr_t max_addr = PHYS_ADDR_MAX;
1678  	struct memblock_region *r;
1679  
1680  	/*
1681  	 * translate the memory @limit size into the max address within one of
1682  	 * the memory memblock regions, if the @limit exceeds the total size
1683  	 * of those regions, max_addr will keep original value PHYS_ADDR_MAX
1684  	 */
1685  	for_each_mem_region(r) {
1686  		if (limit <= r->size) {
1687  			max_addr = r->base + limit;
1688  			break;
1689  		}
1690  		limit -= r->size;
1691  	}
1692  
1693  	return max_addr;
1694  }
1695  
1696  void __init memblock_enforce_memory_limit(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  	/* truncate both memory and reserved regions */
1710  	memblock_remove_range(&memblock.memory, max_addr,
1711  			      PHYS_ADDR_MAX);
1712  	memblock_remove_range(&memblock.reserved, max_addr,
1713  			      PHYS_ADDR_MAX);
1714  }
1715  
1716  void __init memblock_cap_memory_range(phys_addr_t base, phys_addr_t size)
1717  {
1718  	int start_rgn, end_rgn;
1719  	int i, ret;
1720  
1721  	if (!size)
1722  		return;
1723  
1724  	if (!memblock_memory->total_size) {
1725  		pr_warn("%s: No memory registered yet\n", __func__);
1726  		return;
1727  	}
1728  
1729  	ret = memblock_isolate_range(&memblock.memory, base, size,
1730  						&start_rgn, &end_rgn);
1731  	if (ret)
1732  		return;
1733  
1734  	/* remove all the MAP regions */
1735  	for (i = memblock.memory.cnt - 1; i >= end_rgn; i--)
1736  		if (!memblock_is_nomap(&memblock.memory.regions[i]))
1737  			memblock_remove_region(&memblock.memory, i);
1738  
1739  	for (i = start_rgn - 1; i >= 0; i--)
1740  		if (!memblock_is_nomap(&memblock.memory.regions[i]))
1741  			memblock_remove_region(&memblock.memory, i);
1742  
1743  	/* truncate the reserved regions */
1744  	memblock_remove_range(&memblock.reserved, 0, base);
1745  	memblock_remove_range(&memblock.reserved,
1746  			base + size, PHYS_ADDR_MAX);
1747  }
1748  
1749  void __init memblock_mem_limit_remove_map(phys_addr_t limit)
1750  {
1751  	phys_addr_t max_addr;
1752  
1753  	if (!limit)
1754  		return;
1755  
1756  	max_addr = __find_max_addr(limit);
1757  
1758  	/* @limit exceeds the total size of the memory, do nothing */
1759  	if (max_addr == PHYS_ADDR_MAX)
1760  		return;
1761  
1762  	memblock_cap_memory_range(0, max_addr);
1763  }
1764  
1765  static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
1766  {
1767  	unsigned int left = 0, right = type->cnt;
1768  
1769  	do {
1770  		unsigned int mid = (right + left) / 2;
1771  
1772  		if (addr < type->regions[mid].base)
1773  			right = mid;
1774  		else if (addr >= (type->regions[mid].base +
1775  				  type->regions[mid].size))
1776  			left = mid + 1;
1777  		else
1778  			return mid;
1779  	} while (left < right);
1780  	return -1;
1781  }
1782  
1783  bool __init_memblock memblock_is_reserved(phys_addr_t addr)
1784  {
1785  	return memblock_search(&memblock.reserved, addr) != -1;
1786  }
1787  
1788  bool __init_memblock memblock_is_memory(phys_addr_t addr)
1789  {
1790  	return memblock_search(&memblock.memory, addr) != -1;
1791  }
1792  
1793  bool __init_memblock memblock_is_map_memory(phys_addr_t addr)
1794  {
1795  	int i = memblock_search(&memblock.memory, addr);
1796  
1797  	if (i == -1)
1798  		return false;
1799  	return !memblock_is_nomap(&memblock.memory.regions[i]);
1800  }
1801  
1802  int __init_memblock memblock_search_pfn_nid(unsigned long pfn,
1803  			 unsigned long *start_pfn, unsigned long *end_pfn)
1804  {
1805  	struct memblock_type *type = &memblock.memory;
1806  	int mid = memblock_search(type, PFN_PHYS(pfn));
1807  
1808  	if (mid == -1)
1809  		return -1;
1810  
1811  	*start_pfn = PFN_DOWN(type->regions[mid].base);
1812  	*end_pfn = PFN_DOWN(type->regions[mid].base + type->regions[mid].size);
1813  
1814  	return memblock_get_region_node(&type->regions[mid]);
1815  }
1816  
1817  /**
1818   * memblock_is_region_memory - check if a region is a subset of memory
1819   * @base: base of region to check
1820   * @size: size of region to check
1821   *
1822   * Check if the region [@base, @base + @size) is a subset of a memory block.
1823   *
1824   * Return:
1825   * 0 if false, non-zero if true
1826   */
1827  bool __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
1828  {
1829  	int idx = memblock_search(&memblock.memory, base);
1830  	phys_addr_t end = base + memblock_cap_size(base, &size);
1831  
1832  	if (idx == -1)
1833  		return false;
1834  	return (memblock.memory.regions[idx].base +
1835  		 memblock.memory.regions[idx].size) >= end;
1836  }
1837  
1838  /**
1839   * memblock_is_region_reserved - check if a region intersects reserved memory
1840   * @base: base of region to check
1841   * @size: size of region to check
1842   *
1843   * Check if the region [@base, @base + @size) intersects a reserved
1844   * memory block.
1845   *
1846   * Return:
1847   * True if they intersect, false if not.
1848   */
1849  bool __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
1850  {
1851  	return memblock_overlaps_region(&memblock.reserved, base, size);
1852  }
1853  
1854  void __init_memblock memblock_trim_memory(phys_addr_t align)
1855  {
1856  	phys_addr_t start, end, orig_start, orig_end;
1857  	struct memblock_region *r;
1858  
1859  	for_each_mem_region(r) {
1860  		orig_start = r->base;
1861  		orig_end = r->base + r->size;
1862  		start = round_up(orig_start, align);
1863  		end = round_down(orig_end, align);
1864  
1865  		if (start == orig_start && end == orig_end)
1866  			continue;
1867  
1868  		if (start < end) {
1869  			r->base = start;
1870  			r->size = end - start;
1871  		} else {
1872  			memblock_remove_region(&memblock.memory,
1873  					       r - memblock.memory.regions);
1874  			r--;
1875  		}
1876  	}
1877  }
1878  
1879  void __init_memblock memblock_set_current_limit(phys_addr_t limit)
1880  {
1881  	memblock.current_limit = limit;
1882  }
1883  
1884  phys_addr_t __init_memblock memblock_get_current_limit(void)
1885  {
1886  	return memblock.current_limit;
1887  }
1888  
1889  static void __init_memblock memblock_dump(struct memblock_type *type)
1890  {
1891  	phys_addr_t base, end, size;
1892  	enum memblock_flags flags;
1893  	int idx;
1894  	struct memblock_region *rgn;
1895  
1896  	pr_info(" %s.cnt  = 0x%lx\n", type->name, type->cnt);
1897  
1898  	for_each_memblock_type(idx, type, rgn) {
1899  		char nid_buf[32] = "";
1900  
1901  		base = rgn->base;
1902  		size = rgn->size;
1903  		end = base + size - 1;
1904  		flags = rgn->flags;
1905  #ifdef CONFIG_NUMA
1906  		if (memblock_get_region_node(rgn) != MAX_NUMNODES)
1907  			snprintf(nid_buf, sizeof(nid_buf), " on node %d",
1908  				 memblock_get_region_node(rgn));
1909  #endif
1910  		pr_info(" %s[%#x]\t[%pa-%pa], %pa bytes%s flags: %#x\n",
1911  			type->name, idx, &base, &end, &size, nid_buf, flags);
1912  	}
1913  }
1914  
1915  static void __init_memblock __memblock_dump_all(void)
1916  {
1917  	pr_info("MEMBLOCK configuration:\n");
1918  	pr_info(" memory size = %pa reserved size = %pa\n",
1919  		&memblock.memory.total_size,
1920  		&memblock.reserved.total_size);
1921  
1922  	memblock_dump(&memblock.memory);
1923  	memblock_dump(&memblock.reserved);
1924  #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
1925  	memblock_dump(&physmem);
1926  #endif
1927  }
1928  
1929  void __init_memblock memblock_dump_all(void)
1930  {
1931  	if (memblock_debug)
1932  		__memblock_dump_all();
1933  }
1934  
1935  void __init memblock_allow_resize(void)
1936  {
1937  	memblock_can_resize = 1;
1938  }
1939  
1940  static int __init early_memblock(char *p)
1941  {
1942  	if (p && strstr(p, "debug"))
1943  		memblock_debug = 1;
1944  	return 0;
1945  }
1946  early_param("memblock", early_memblock);
1947  
1948  static void __init free_memmap(unsigned long start_pfn, unsigned long end_pfn)
1949  {
1950  	struct page *start_pg, *end_pg;
1951  	phys_addr_t pg, pgend;
1952  
1953  	/*
1954  	 * Convert start_pfn/end_pfn to a struct page pointer.
1955  	 */
1956  	start_pg = pfn_to_page(start_pfn - 1) + 1;
1957  	end_pg = pfn_to_page(end_pfn - 1) + 1;
1958  
1959  	/*
1960  	 * Convert to physical addresses, and round start upwards and end
1961  	 * downwards.
1962  	 */
1963  	pg = PAGE_ALIGN(__pa(start_pg));
1964  	pgend = __pa(end_pg) & PAGE_MASK;
1965  
1966  	/*
1967  	 * If there are free pages between these, free the section of the
1968  	 * memmap array.
1969  	 */
1970  	if (pg < pgend)
1971  		memblock_phys_free(pg, pgend - pg);
1972  }
1973  
1974  /*
1975   * The mem_map array can get very big.  Free the unused area of the memory map.
1976   */
1977  static void __init free_unused_memmap(void)
1978  {
1979  	unsigned long start, end, prev_end = 0;
1980  	int i;
1981  
1982  	if (!IS_ENABLED(CONFIG_HAVE_ARCH_PFN_VALID) ||
1983  	    IS_ENABLED(CONFIG_SPARSEMEM_VMEMMAP))
1984  		return;
1985  
1986  	/*
1987  	 * This relies on each bank being in address order.
1988  	 * The banks are sorted previously in bootmem_init().
1989  	 */
1990  	for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, NULL) {
1991  #ifdef CONFIG_SPARSEMEM
1992  		/*
1993  		 * Take care not to free memmap entries that don't exist
1994  		 * due to SPARSEMEM sections which aren't present.
1995  		 */
1996  		start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
1997  #endif
1998  		/*
1999  		 * Align down here since many operations in VM subsystem
2000  		 * presume that there are no holes in the memory map inside
2001  		 * a pageblock
2002  		 */
2003  		start = round_down(start, pageblock_nr_pages);
2004  
2005  		/*
2006  		 * If we had a previous bank, and there is a space
2007  		 * between the current bank and the previous, free it.
2008  		 */
2009  		if (prev_end && prev_end < start)
2010  			free_memmap(prev_end, start);
2011  
2012  		/*
2013  		 * Align up here since many operations in VM subsystem
2014  		 * presume that there are no holes in the memory map inside
2015  		 * a pageblock
2016  		 */
2017  		prev_end = ALIGN(end, pageblock_nr_pages);
2018  	}
2019  
2020  #ifdef CONFIG_SPARSEMEM
2021  	if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION)) {
2022  		prev_end = ALIGN(end, pageblock_nr_pages);
2023  		free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
2024  	}
2025  #endif
2026  }
2027  
2028  static void __init __free_pages_memory(unsigned long start, unsigned long end)
2029  {
2030  	int order;
2031  
2032  	while (start < end) {
2033  		order = min(MAX_ORDER - 1UL, __ffs(start));
2034  
2035  		while (start + (1UL << order) > end)
2036  			order--;
2037  
2038  		memblock_free_pages(pfn_to_page(start), start, order);
2039  
2040  		start += (1UL << order);
2041  	}
2042  }
2043  
2044  static unsigned long __init __free_memory_core(phys_addr_t start,
2045  				 phys_addr_t end)
2046  {
2047  	unsigned long start_pfn = PFN_UP(start);
2048  	unsigned long end_pfn = min_t(unsigned long,
2049  				      PFN_DOWN(end), max_low_pfn);
2050  
2051  	if (start_pfn >= end_pfn)
2052  		return 0;
2053  
2054  	__free_pages_memory(start_pfn, end_pfn);
2055  
2056  	return end_pfn - start_pfn;
2057  }
2058  
2059  static void __init memmap_init_reserved_pages(void)
2060  {
2061  	struct memblock_region *region;
2062  	phys_addr_t start, end;
2063  	u64 i;
2064  
2065  	/* initialize struct pages for the reserved regions */
2066  	for_each_reserved_mem_range(i, &start, &end)
2067  		reserve_bootmem_region(start, end);
2068  
2069  	/* and also treat struct pages for the NOMAP regions as PageReserved */
2070  	for_each_mem_region(region) {
2071  		if (memblock_is_nomap(region)) {
2072  			start = region->base;
2073  			end = start + region->size;
2074  			reserve_bootmem_region(start, end);
2075  		}
2076  	}
2077  }
2078  
2079  static unsigned long __init free_low_memory_core_early(void)
2080  {
2081  	unsigned long count = 0;
2082  	phys_addr_t start, end;
2083  	u64 i;
2084  
2085  	memblock_clear_hotplug(0, -1);
2086  
2087  	memmap_init_reserved_pages();
2088  
2089  	/*
2090  	 * We need to use NUMA_NO_NODE instead of NODE_DATA(0)->node_id
2091  	 *  because in some case like Node0 doesn't have RAM installed
2092  	 *  low ram will be on Node1
2093  	 */
2094  	for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE, &start, &end,
2095  				NULL)
2096  		count += __free_memory_core(start, end);
2097  
2098  	return count;
2099  }
2100  
2101  static int reset_managed_pages_done __initdata;
2102  
2103  void reset_node_managed_pages(pg_data_t *pgdat)
2104  {
2105  	struct zone *z;
2106  
2107  	for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
2108  		atomic_long_set(&z->managed_pages, 0);
2109  }
2110  
2111  void __init reset_all_zones_managed_pages(void)
2112  {
2113  	struct pglist_data *pgdat;
2114  
2115  	if (reset_managed_pages_done)
2116  		return;
2117  
2118  	for_each_online_pgdat(pgdat)
2119  		reset_node_managed_pages(pgdat);
2120  
2121  	reset_managed_pages_done = 1;
2122  }
2123  
2124  /**
2125   * memblock_free_all - release free pages to the buddy allocator
2126   */
2127  void __init memblock_free_all(void)
2128  {
2129  	unsigned long pages;
2130  
2131  	free_unused_memmap();
2132  	reset_all_zones_managed_pages();
2133  
2134  	pages = free_low_memory_core_early();
2135  	totalram_pages_add(pages);
2136  }
2137  
2138  #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_ARCH_KEEP_MEMBLOCK)
2139  
2140  static int memblock_debug_show(struct seq_file *m, void *private)
2141  {
2142  	struct memblock_type *type = m->private;
2143  	struct memblock_region *reg;
2144  	int i;
2145  	phys_addr_t end;
2146  
2147  	for (i = 0; i < type->cnt; i++) {
2148  		reg = &type->regions[i];
2149  		end = reg->base + reg->size - 1;
2150  
2151  		seq_printf(m, "%4d: ", i);
2152  		seq_printf(m, "%pa..%pa\n", &reg->base, &end);
2153  	}
2154  	return 0;
2155  }
2156  DEFINE_SHOW_ATTRIBUTE(memblock_debug);
2157  
2158  static int __init memblock_init_debugfs(void)
2159  {
2160  	struct dentry *root = debugfs_create_dir("memblock", NULL);
2161  
2162  	debugfs_create_file("memory", 0444, root,
2163  			    &memblock.memory, &memblock_debug_fops);
2164  	debugfs_create_file("reserved", 0444, root,
2165  			    &memblock.reserved, &memblock_debug_fops);
2166  #ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
2167  	debugfs_create_file("physmem", 0444, root, &physmem,
2168  			    &memblock_debug_fops);
2169  #endif
2170  
2171  	return 0;
2172  }
2173  __initcall(memblock_init_debugfs);
2174  
2175  #endif /* CONFIG_DEBUG_FS */
2176