xref: /linux/mm/memblock.c (revision d97b46a64674a267bc41c9e16132ee2a98c3347d)
1 /*
2  * Procedures for maintaining information about logical memory blocks.
3  *
4  * Peter Bergner, IBM Corp.	June 2001.
5  * Copyright (C) 2001 Peter Bergner.
6  *
7  *      This program is free software; you can redistribute it and/or
8  *      modify it under the terms of the GNU General Public License
9  *      as published by the Free Software Foundation; either version
10  *      2 of the License, or (at your option) any later version.
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/init.h>
16 #include <linux/bitops.h>
17 #include <linux/poison.h>
18 #include <linux/pfn.h>
19 #include <linux/debugfs.h>
20 #include <linux/seq_file.h>
21 #include <linux/memblock.h>
22 
23 static struct memblock_region memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS] __initdata_memblock;
24 static struct memblock_region memblock_reserved_init_regions[INIT_MEMBLOCK_REGIONS] __initdata_memblock;
25 
26 struct memblock memblock __initdata_memblock = {
27 	.memory.regions		= memblock_memory_init_regions,
28 	.memory.cnt		= 1,	/* empty dummy entry */
29 	.memory.max		= INIT_MEMBLOCK_REGIONS,
30 
31 	.reserved.regions	= memblock_reserved_init_regions,
32 	.reserved.cnt		= 1,	/* empty dummy entry */
33 	.reserved.max		= INIT_MEMBLOCK_REGIONS,
34 
35 	.current_limit		= MEMBLOCK_ALLOC_ANYWHERE,
36 };
37 
38 int memblock_debug __initdata_memblock;
39 static int memblock_can_resize __initdata_memblock;
40 static int memblock_memory_in_slab __initdata_memblock = 0;
41 static int memblock_reserved_in_slab __initdata_memblock = 0;
42 
43 /* inline so we don't get a warning when pr_debug is compiled out */
44 static inline const char *memblock_type_name(struct memblock_type *type)
45 {
46 	if (type == &memblock.memory)
47 		return "memory";
48 	else if (type == &memblock.reserved)
49 		return "reserved";
50 	else
51 		return "unknown";
52 }
53 
54 /* adjust *@size so that (@base + *@size) doesn't overflow, return new size */
55 static inline phys_addr_t memblock_cap_size(phys_addr_t base, phys_addr_t *size)
56 {
57 	return *size = min(*size, (phys_addr_t)ULLONG_MAX - base);
58 }
59 
60 /*
61  * Address comparison utilities
62  */
63 static unsigned long __init_memblock memblock_addrs_overlap(phys_addr_t base1, phys_addr_t size1,
64 				       phys_addr_t base2, phys_addr_t size2)
65 {
66 	return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
67 }
68 
69 static long __init_memblock memblock_overlaps_region(struct memblock_type *type,
70 					phys_addr_t base, phys_addr_t size)
71 {
72 	unsigned long i;
73 
74 	for (i = 0; i < type->cnt; i++) {
75 		phys_addr_t rgnbase = type->regions[i].base;
76 		phys_addr_t rgnsize = type->regions[i].size;
77 		if (memblock_addrs_overlap(base, size, rgnbase, rgnsize))
78 			break;
79 	}
80 
81 	return (i < type->cnt) ? i : -1;
82 }
83 
84 /**
85  * memblock_find_in_range_node - find free area in given range and node
86  * @start: start of candidate range
87  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_{ANYWHERE|ACCESSIBLE}
88  * @size: size of free area to find
89  * @align: alignment of free area to find
90  * @nid: nid of the free area to find, %MAX_NUMNODES for any node
91  *
92  * Find @size free area aligned to @align in the specified range and node.
93  *
94  * RETURNS:
95  * Found address on success, %0 on failure.
96  */
97 phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t start,
98 					phys_addr_t end, phys_addr_t size,
99 					phys_addr_t align, int nid)
100 {
101 	phys_addr_t this_start, this_end, cand;
102 	u64 i;
103 
104 	/* pump up @end */
105 	if (end == MEMBLOCK_ALLOC_ACCESSIBLE)
106 		end = memblock.current_limit;
107 
108 	/* avoid allocating the first page */
109 	start = max_t(phys_addr_t, start, PAGE_SIZE);
110 	end = max(start, end);
111 
112 	for_each_free_mem_range_reverse(i, nid, &this_start, &this_end, NULL) {
113 		this_start = clamp(this_start, start, end);
114 		this_end = clamp(this_end, start, end);
115 
116 		if (this_end < size)
117 			continue;
118 
119 		cand = round_down(this_end - size, align);
120 		if (cand >= this_start)
121 			return cand;
122 	}
123 	return 0;
124 }
125 
126 /**
127  * memblock_find_in_range - find free area in given range
128  * @start: start of candidate range
129  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_{ANYWHERE|ACCESSIBLE}
130  * @size: size of free area to find
131  * @align: alignment of free area to find
132  *
133  * Find @size free area aligned to @align in the specified range.
134  *
135  * RETURNS:
136  * Found address on success, %0 on failure.
137  */
138 phys_addr_t __init_memblock memblock_find_in_range(phys_addr_t start,
139 					phys_addr_t end, phys_addr_t size,
140 					phys_addr_t align)
141 {
142 	return memblock_find_in_range_node(start, end, size, align,
143 					   MAX_NUMNODES);
144 }
145 
146 /*
147  * Free memblock.reserved.regions
148  */
149 int __init_memblock memblock_free_reserved_regions(void)
150 {
151 	if (memblock.reserved.regions == memblock_reserved_init_regions)
152 		return 0;
153 
154 	return memblock_free(__pa(memblock.reserved.regions),
155 		 sizeof(struct memblock_region) * memblock.reserved.max);
156 }
157 
158 /*
159  * Reserve memblock.reserved.regions
160  */
161 int __init_memblock memblock_reserve_reserved_regions(void)
162 {
163 	if (memblock.reserved.regions == memblock_reserved_init_regions)
164 		return 0;
165 
166 	return memblock_reserve(__pa(memblock.reserved.regions),
167 		 sizeof(struct memblock_region) * memblock.reserved.max);
168 }
169 
170 static void __init_memblock memblock_remove_region(struct memblock_type *type, unsigned long r)
171 {
172 	type->total_size -= type->regions[r].size;
173 	memmove(&type->regions[r], &type->regions[r + 1],
174 		(type->cnt - (r + 1)) * sizeof(type->regions[r]));
175 	type->cnt--;
176 
177 	/* Special case for empty arrays */
178 	if (type->cnt == 0) {
179 		WARN_ON(type->total_size != 0);
180 		type->cnt = 1;
181 		type->regions[0].base = 0;
182 		type->regions[0].size = 0;
183 		memblock_set_region_node(&type->regions[0], MAX_NUMNODES);
184 	}
185 }
186 
187 static int __init_memblock memblock_double_array(struct memblock_type *type)
188 {
189 	struct memblock_region *new_array, *old_array;
190 	phys_addr_t old_size, new_size, addr;
191 	int use_slab = slab_is_available();
192 	int *in_slab;
193 
194 	/* We don't allow resizing until we know about the reserved regions
195 	 * of memory that aren't suitable for allocation
196 	 */
197 	if (!memblock_can_resize)
198 		return -1;
199 
200 	/* Calculate new doubled size */
201 	old_size = type->max * sizeof(struct memblock_region);
202 	new_size = old_size << 1;
203 
204 	/* Retrieve the slab flag */
205 	if (type == &memblock.memory)
206 		in_slab = &memblock_memory_in_slab;
207 	else
208 		in_slab = &memblock_reserved_in_slab;
209 
210 	/* Try to find some space for it.
211 	 *
212 	 * WARNING: We assume that either slab_is_available() and we use it or
213 	 * we use MEMBLOCK for allocations. That means that this is unsafe to use
214 	 * when bootmem is currently active (unless bootmem itself is implemented
215 	 * on top of MEMBLOCK which isn't the case yet)
216 	 *
217 	 * This should however not be an issue for now, as we currently only
218 	 * call into MEMBLOCK while it's still active, or much later when slab is
219 	 * active for memory hotplug operations
220 	 */
221 	if (use_slab) {
222 		new_array = kmalloc(new_size, GFP_KERNEL);
223 		addr = new_array ? __pa(new_array) : 0;
224 	} else {
225 		addr = memblock_find_in_range(0, MEMBLOCK_ALLOC_ACCESSIBLE, new_size, sizeof(phys_addr_t));
226 		new_array = addr ? __va(addr) : 0;
227 	}
228 	if (!addr) {
229 		pr_err("memblock: Failed to double %s array from %ld to %ld entries !\n",
230 		       memblock_type_name(type), type->max, type->max * 2);
231 		return -1;
232 	}
233 
234 	memblock_dbg("memblock: %s array is doubled to %ld at [%#010llx-%#010llx]",
235 		 memblock_type_name(type), type->max * 2, (u64)addr, (u64)addr + new_size - 1);
236 
237 	/* Found space, we now need to move the array over before
238 	 * we add the reserved region since it may be our reserved
239 	 * array itself that is full.
240 	 */
241 	memcpy(new_array, type->regions, old_size);
242 	memset(new_array + type->max, 0, old_size);
243 	old_array = type->regions;
244 	type->regions = new_array;
245 	type->max <<= 1;
246 
247 	/* Free old array. We needn't free it if the array is the
248 	 * static one
249 	 */
250 	if (*in_slab)
251 		kfree(old_array);
252 	else if (old_array != memblock_memory_init_regions &&
253 		 old_array != memblock_reserved_init_regions)
254 		memblock_free(__pa(old_array), old_size);
255 
256 	/* Reserve the new array if that comes from the memblock.
257 	 * Otherwise, we needn't do it
258 	 */
259 	if (!use_slab)
260 		BUG_ON(memblock_reserve(addr, new_size));
261 
262 	/* Update slab flag */
263 	*in_slab = use_slab;
264 
265 	return 0;
266 }
267 
268 /**
269  * memblock_merge_regions - merge neighboring compatible regions
270  * @type: memblock type to scan
271  *
272  * Scan @type and merge neighboring compatible regions.
273  */
274 static void __init_memblock memblock_merge_regions(struct memblock_type *type)
275 {
276 	int i = 0;
277 
278 	/* cnt never goes below 1 */
279 	while (i < type->cnt - 1) {
280 		struct memblock_region *this = &type->regions[i];
281 		struct memblock_region *next = &type->regions[i + 1];
282 
283 		if (this->base + this->size != next->base ||
284 		    memblock_get_region_node(this) !=
285 		    memblock_get_region_node(next)) {
286 			BUG_ON(this->base + this->size > next->base);
287 			i++;
288 			continue;
289 		}
290 
291 		this->size += next->size;
292 		memmove(next, next + 1, (type->cnt - (i + 1)) * sizeof(*next));
293 		type->cnt--;
294 	}
295 }
296 
297 /**
298  * memblock_insert_region - insert new memblock region
299  * @type: memblock type to insert into
300  * @idx: index for the insertion point
301  * @base: base address of the new region
302  * @size: size of the new region
303  *
304  * Insert new memblock region [@base,@base+@size) into @type at @idx.
305  * @type must already have extra room to accomodate the new region.
306  */
307 static void __init_memblock memblock_insert_region(struct memblock_type *type,
308 						   int idx, phys_addr_t base,
309 						   phys_addr_t size, int nid)
310 {
311 	struct memblock_region *rgn = &type->regions[idx];
312 
313 	BUG_ON(type->cnt >= type->max);
314 	memmove(rgn + 1, rgn, (type->cnt - idx) * sizeof(*rgn));
315 	rgn->base = base;
316 	rgn->size = size;
317 	memblock_set_region_node(rgn, nid);
318 	type->cnt++;
319 	type->total_size += size;
320 }
321 
322 /**
323  * memblock_add_region - add new memblock region
324  * @type: memblock type to add new region into
325  * @base: base address of the new region
326  * @size: size of the new region
327  * @nid: nid of the new region
328  *
329  * Add new memblock region [@base,@base+@size) into @type.  The new region
330  * is allowed to overlap with existing ones - overlaps don't affect already
331  * existing regions.  @type is guaranteed to be minimal (all neighbouring
332  * compatible regions are merged) after the addition.
333  *
334  * RETURNS:
335  * 0 on success, -errno on failure.
336  */
337 static int __init_memblock memblock_add_region(struct memblock_type *type,
338 				phys_addr_t base, phys_addr_t size, int nid)
339 {
340 	bool insert = false;
341 	phys_addr_t obase = base;
342 	phys_addr_t end = base + memblock_cap_size(base, &size);
343 	int i, nr_new;
344 
345 	if (!size)
346 		return 0;
347 
348 	/* special case for empty array */
349 	if (type->regions[0].size == 0) {
350 		WARN_ON(type->cnt != 1 || type->total_size);
351 		type->regions[0].base = base;
352 		type->regions[0].size = size;
353 		memblock_set_region_node(&type->regions[0], nid);
354 		type->total_size = size;
355 		return 0;
356 	}
357 repeat:
358 	/*
359 	 * The following is executed twice.  Once with %false @insert and
360 	 * then with %true.  The first counts the number of regions needed
361 	 * to accomodate the new area.  The second actually inserts them.
362 	 */
363 	base = obase;
364 	nr_new = 0;
365 
366 	for (i = 0; i < type->cnt; i++) {
367 		struct memblock_region *rgn = &type->regions[i];
368 		phys_addr_t rbase = rgn->base;
369 		phys_addr_t rend = rbase + rgn->size;
370 
371 		if (rbase >= end)
372 			break;
373 		if (rend <= base)
374 			continue;
375 		/*
376 		 * @rgn overlaps.  If it separates the lower part of new
377 		 * area, insert that portion.
378 		 */
379 		if (rbase > base) {
380 			nr_new++;
381 			if (insert)
382 				memblock_insert_region(type, i++, base,
383 						       rbase - base, nid);
384 		}
385 		/* area below @rend is dealt with, forget about it */
386 		base = min(rend, end);
387 	}
388 
389 	/* insert the remaining portion */
390 	if (base < end) {
391 		nr_new++;
392 		if (insert)
393 			memblock_insert_region(type, i, base, end - base, nid);
394 	}
395 
396 	/*
397 	 * If this was the first round, resize array and repeat for actual
398 	 * insertions; otherwise, merge and return.
399 	 */
400 	if (!insert) {
401 		while (type->cnt + nr_new > type->max)
402 			if (memblock_double_array(type) < 0)
403 				return -ENOMEM;
404 		insert = true;
405 		goto repeat;
406 	} else {
407 		memblock_merge_regions(type);
408 		return 0;
409 	}
410 }
411 
412 int __init_memblock memblock_add_node(phys_addr_t base, phys_addr_t size,
413 				       int nid)
414 {
415 	return memblock_add_region(&memblock.memory, base, size, nid);
416 }
417 
418 int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
419 {
420 	return memblock_add_region(&memblock.memory, base, size, MAX_NUMNODES);
421 }
422 
423 /**
424  * memblock_isolate_range - isolate given range into disjoint memblocks
425  * @type: memblock type to isolate range for
426  * @base: base of range to isolate
427  * @size: size of range to isolate
428  * @start_rgn: out parameter for the start of isolated region
429  * @end_rgn: out parameter for the end of isolated region
430  *
431  * Walk @type and ensure that regions don't cross the boundaries defined by
432  * [@base,@base+@size).  Crossing regions are split at the boundaries,
433  * which may create at most two more regions.  The index of the first
434  * region inside the range is returned in *@start_rgn and end in *@end_rgn.
435  *
436  * RETURNS:
437  * 0 on success, -errno on failure.
438  */
439 static int __init_memblock memblock_isolate_range(struct memblock_type *type,
440 					phys_addr_t base, phys_addr_t size,
441 					int *start_rgn, int *end_rgn)
442 {
443 	phys_addr_t end = base + memblock_cap_size(base, &size);
444 	int i;
445 
446 	*start_rgn = *end_rgn = 0;
447 
448 	if (!size)
449 		return 0;
450 
451 	/* we'll create at most two more regions */
452 	while (type->cnt + 2 > type->max)
453 		if (memblock_double_array(type) < 0)
454 			return -ENOMEM;
455 
456 	for (i = 0; i < type->cnt; i++) {
457 		struct memblock_region *rgn = &type->regions[i];
458 		phys_addr_t rbase = rgn->base;
459 		phys_addr_t rend = rbase + rgn->size;
460 
461 		if (rbase >= end)
462 			break;
463 		if (rend <= base)
464 			continue;
465 
466 		if (rbase < base) {
467 			/*
468 			 * @rgn intersects from below.  Split and continue
469 			 * to process the next region - the new top half.
470 			 */
471 			rgn->base = base;
472 			rgn->size -= base - rbase;
473 			type->total_size -= base - rbase;
474 			memblock_insert_region(type, i, rbase, base - rbase,
475 					       memblock_get_region_node(rgn));
476 		} else if (rend > end) {
477 			/*
478 			 * @rgn intersects from above.  Split and redo the
479 			 * current region - the new bottom half.
480 			 */
481 			rgn->base = end;
482 			rgn->size -= end - rbase;
483 			type->total_size -= end - rbase;
484 			memblock_insert_region(type, i--, rbase, end - rbase,
485 					       memblock_get_region_node(rgn));
486 		} else {
487 			/* @rgn is fully contained, record it */
488 			if (!*end_rgn)
489 				*start_rgn = i;
490 			*end_rgn = i + 1;
491 		}
492 	}
493 
494 	return 0;
495 }
496 
497 static int __init_memblock __memblock_remove(struct memblock_type *type,
498 					     phys_addr_t base, phys_addr_t size)
499 {
500 	int start_rgn, end_rgn;
501 	int i, ret;
502 
503 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
504 	if (ret)
505 		return ret;
506 
507 	for (i = end_rgn - 1; i >= start_rgn; i--)
508 		memblock_remove_region(type, i);
509 	return 0;
510 }
511 
512 int __init_memblock memblock_remove(phys_addr_t base, phys_addr_t size)
513 {
514 	return __memblock_remove(&memblock.memory, base, size);
515 }
516 
517 int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)
518 {
519 	memblock_dbg("   memblock_free: [%#016llx-%#016llx] %pF\n",
520 		     (unsigned long long)base,
521 		     (unsigned long long)base + size,
522 		     (void *)_RET_IP_);
523 
524 	return __memblock_remove(&memblock.reserved, base, size);
525 }
526 
527 int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
528 {
529 	struct memblock_type *_rgn = &memblock.reserved;
530 
531 	memblock_dbg("memblock_reserve: [%#016llx-%#016llx] %pF\n",
532 		     (unsigned long long)base,
533 		     (unsigned long long)base + size,
534 		     (void *)_RET_IP_);
535 
536 	return memblock_add_region(_rgn, base, size, MAX_NUMNODES);
537 }
538 
539 /**
540  * __next_free_mem_range - next function for for_each_free_mem_range()
541  * @idx: pointer to u64 loop variable
542  * @nid: nid: node selector, %MAX_NUMNODES for all nodes
543  * @p_start: ptr to phys_addr_t for start address of the range, can be %NULL
544  * @p_end: ptr to phys_addr_t for end address of the range, can be %NULL
545  * @p_nid: ptr to int for nid of the range, can be %NULL
546  *
547  * Find the first free area from *@idx which matches @nid, fill the out
548  * parameters, and update *@idx for the next iteration.  The lower 32bit of
549  * *@idx contains index into memory region and the upper 32bit indexes the
550  * areas before each reserved region.  For example, if reserved regions
551  * look like the following,
552  *
553  *	0:[0-16), 1:[32-48), 2:[128-130)
554  *
555  * The upper 32bit indexes the following regions.
556  *
557  *	0:[0-0), 1:[16-32), 2:[48-128), 3:[130-MAX)
558  *
559  * As both region arrays are sorted, the function advances the two indices
560  * in lockstep and returns each intersection.
561  */
562 void __init_memblock __next_free_mem_range(u64 *idx, int nid,
563 					   phys_addr_t *out_start,
564 					   phys_addr_t *out_end, int *out_nid)
565 {
566 	struct memblock_type *mem = &memblock.memory;
567 	struct memblock_type *rsv = &memblock.reserved;
568 	int mi = *idx & 0xffffffff;
569 	int ri = *idx >> 32;
570 
571 	for ( ; mi < mem->cnt; mi++) {
572 		struct memblock_region *m = &mem->regions[mi];
573 		phys_addr_t m_start = m->base;
574 		phys_addr_t m_end = m->base + m->size;
575 
576 		/* only memory regions are associated with nodes, check it */
577 		if (nid != MAX_NUMNODES && nid != memblock_get_region_node(m))
578 			continue;
579 
580 		/* scan areas before each reservation for intersection */
581 		for ( ; ri < rsv->cnt + 1; ri++) {
582 			struct memblock_region *r = &rsv->regions[ri];
583 			phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
584 			phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
585 
586 			/* if ri advanced past mi, break out to advance mi */
587 			if (r_start >= m_end)
588 				break;
589 			/* if the two regions intersect, we're done */
590 			if (m_start < r_end) {
591 				if (out_start)
592 					*out_start = max(m_start, r_start);
593 				if (out_end)
594 					*out_end = min(m_end, r_end);
595 				if (out_nid)
596 					*out_nid = memblock_get_region_node(m);
597 				/*
598 				 * The region which ends first is advanced
599 				 * for the next iteration.
600 				 */
601 				if (m_end <= r_end)
602 					mi++;
603 				else
604 					ri++;
605 				*idx = (u32)mi | (u64)ri << 32;
606 				return;
607 			}
608 		}
609 	}
610 
611 	/* signal end of iteration */
612 	*idx = ULLONG_MAX;
613 }
614 
615 /**
616  * __next_free_mem_range_rev - next function for for_each_free_mem_range_reverse()
617  * @idx: pointer to u64 loop variable
618  * @nid: nid: node selector, %MAX_NUMNODES for all nodes
619  * @p_start: ptr to phys_addr_t for start address of the range, can be %NULL
620  * @p_end: ptr to phys_addr_t for end address of the range, can be %NULL
621  * @p_nid: ptr to int for nid of the range, can be %NULL
622  *
623  * Reverse of __next_free_mem_range().
624  */
625 void __init_memblock __next_free_mem_range_rev(u64 *idx, int nid,
626 					   phys_addr_t *out_start,
627 					   phys_addr_t *out_end, int *out_nid)
628 {
629 	struct memblock_type *mem = &memblock.memory;
630 	struct memblock_type *rsv = &memblock.reserved;
631 	int mi = *idx & 0xffffffff;
632 	int ri = *idx >> 32;
633 
634 	if (*idx == (u64)ULLONG_MAX) {
635 		mi = mem->cnt - 1;
636 		ri = rsv->cnt;
637 	}
638 
639 	for ( ; mi >= 0; mi--) {
640 		struct memblock_region *m = &mem->regions[mi];
641 		phys_addr_t m_start = m->base;
642 		phys_addr_t m_end = m->base + m->size;
643 
644 		/* only memory regions are associated with nodes, check it */
645 		if (nid != MAX_NUMNODES && nid != memblock_get_region_node(m))
646 			continue;
647 
648 		/* scan areas before each reservation for intersection */
649 		for ( ; ri >= 0; ri--) {
650 			struct memblock_region *r = &rsv->regions[ri];
651 			phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
652 			phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
653 
654 			/* if ri advanced past mi, break out to advance mi */
655 			if (r_end <= m_start)
656 				break;
657 			/* if the two regions intersect, we're done */
658 			if (m_end > r_start) {
659 				if (out_start)
660 					*out_start = max(m_start, r_start);
661 				if (out_end)
662 					*out_end = min(m_end, r_end);
663 				if (out_nid)
664 					*out_nid = memblock_get_region_node(m);
665 
666 				if (m_start >= r_start)
667 					mi--;
668 				else
669 					ri--;
670 				*idx = (u32)mi | (u64)ri << 32;
671 				return;
672 			}
673 		}
674 	}
675 
676 	*idx = ULLONG_MAX;
677 }
678 
679 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
680 /*
681  * Common iterator interface used to define for_each_mem_range().
682  */
683 void __init_memblock __next_mem_pfn_range(int *idx, int nid,
684 				unsigned long *out_start_pfn,
685 				unsigned long *out_end_pfn, int *out_nid)
686 {
687 	struct memblock_type *type = &memblock.memory;
688 	struct memblock_region *r;
689 
690 	while (++*idx < type->cnt) {
691 		r = &type->regions[*idx];
692 
693 		if (PFN_UP(r->base) >= PFN_DOWN(r->base + r->size))
694 			continue;
695 		if (nid == MAX_NUMNODES || nid == r->nid)
696 			break;
697 	}
698 	if (*idx >= type->cnt) {
699 		*idx = -1;
700 		return;
701 	}
702 
703 	if (out_start_pfn)
704 		*out_start_pfn = PFN_UP(r->base);
705 	if (out_end_pfn)
706 		*out_end_pfn = PFN_DOWN(r->base + r->size);
707 	if (out_nid)
708 		*out_nid = r->nid;
709 }
710 
711 /**
712  * memblock_set_node - set node ID on memblock regions
713  * @base: base of area to set node ID for
714  * @size: size of area to set node ID for
715  * @nid: node ID to set
716  *
717  * Set the nid of memblock memory regions in [@base,@base+@size) to @nid.
718  * Regions which cross the area boundaries are split as necessary.
719  *
720  * RETURNS:
721  * 0 on success, -errno on failure.
722  */
723 int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
724 				      int nid)
725 {
726 	struct memblock_type *type = &memblock.memory;
727 	int start_rgn, end_rgn;
728 	int i, ret;
729 
730 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
731 	if (ret)
732 		return ret;
733 
734 	for (i = start_rgn; i < end_rgn; i++)
735 		type->regions[i].nid = nid;
736 
737 	memblock_merge_regions(type);
738 	return 0;
739 }
740 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
741 
742 static phys_addr_t __init memblock_alloc_base_nid(phys_addr_t size,
743 					phys_addr_t align, phys_addr_t max_addr,
744 					int nid)
745 {
746 	phys_addr_t found;
747 
748 	/* align @size to avoid excessive fragmentation on reserved array */
749 	size = round_up(size, align);
750 
751 	found = memblock_find_in_range_node(0, max_addr, size, align, nid);
752 	if (found && !memblock_reserve(found, size))
753 		return found;
754 
755 	return 0;
756 }
757 
758 phys_addr_t __init memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int nid)
759 {
760 	return memblock_alloc_base_nid(size, align, MEMBLOCK_ALLOC_ACCESSIBLE, nid);
761 }
762 
763 phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
764 {
765 	return memblock_alloc_base_nid(size, align, max_addr, MAX_NUMNODES);
766 }
767 
768 phys_addr_t __init memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
769 {
770 	phys_addr_t alloc;
771 
772 	alloc = __memblock_alloc_base(size, align, max_addr);
773 
774 	if (alloc == 0)
775 		panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
776 		      (unsigned long long) size, (unsigned long long) max_addr);
777 
778 	return alloc;
779 }
780 
781 phys_addr_t __init memblock_alloc(phys_addr_t size, phys_addr_t align)
782 {
783 	return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
784 }
785 
786 phys_addr_t __init memblock_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
787 {
788 	phys_addr_t res = memblock_alloc_nid(size, align, nid);
789 
790 	if (res)
791 		return res;
792 	return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
793 }
794 
795 
796 /*
797  * Remaining API functions
798  */
799 
800 phys_addr_t __init memblock_phys_mem_size(void)
801 {
802 	return memblock.memory.total_size;
803 }
804 
805 /* lowest address */
806 phys_addr_t __init_memblock memblock_start_of_DRAM(void)
807 {
808 	return memblock.memory.regions[0].base;
809 }
810 
811 phys_addr_t __init_memblock memblock_end_of_DRAM(void)
812 {
813 	int idx = memblock.memory.cnt - 1;
814 
815 	return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
816 }
817 
818 void __init memblock_enforce_memory_limit(phys_addr_t limit)
819 {
820 	unsigned long i;
821 	phys_addr_t max_addr = (phys_addr_t)ULLONG_MAX;
822 
823 	if (!limit)
824 		return;
825 
826 	/* find out max address */
827 	for (i = 0; i < memblock.memory.cnt; i++) {
828 		struct memblock_region *r = &memblock.memory.regions[i];
829 
830 		if (limit <= r->size) {
831 			max_addr = r->base + limit;
832 			break;
833 		}
834 		limit -= r->size;
835 	}
836 
837 	/* truncate both memory and reserved regions */
838 	__memblock_remove(&memblock.memory, max_addr, (phys_addr_t)ULLONG_MAX);
839 	__memblock_remove(&memblock.reserved, max_addr, (phys_addr_t)ULLONG_MAX);
840 }
841 
842 static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
843 {
844 	unsigned int left = 0, right = type->cnt;
845 
846 	do {
847 		unsigned int mid = (right + left) / 2;
848 
849 		if (addr < type->regions[mid].base)
850 			right = mid;
851 		else if (addr >= (type->regions[mid].base +
852 				  type->regions[mid].size))
853 			left = mid + 1;
854 		else
855 			return mid;
856 	} while (left < right);
857 	return -1;
858 }
859 
860 int __init memblock_is_reserved(phys_addr_t addr)
861 {
862 	return memblock_search(&memblock.reserved, addr) != -1;
863 }
864 
865 int __init_memblock memblock_is_memory(phys_addr_t addr)
866 {
867 	return memblock_search(&memblock.memory, addr) != -1;
868 }
869 
870 int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
871 {
872 	int idx = memblock_search(&memblock.memory, base);
873 	phys_addr_t end = base + memblock_cap_size(base, &size);
874 
875 	if (idx == -1)
876 		return 0;
877 	return memblock.memory.regions[idx].base <= base &&
878 		(memblock.memory.regions[idx].base +
879 		 memblock.memory.regions[idx].size) >= end;
880 }
881 
882 int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
883 {
884 	memblock_cap_size(base, &size);
885 	return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;
886 }
887 
888 
889 void __init_memblock memblock_set_current_limit(phys_addr_t limit)
890 {
891 	memblock.current_limit = limit;
892 }
893 
894 static void __init_memblock memblock_dump(struct memblock_type *type, char *name)
895 {
896 	unsigned long long base, size;
897 	int i;
898 
899 	pr_info(" %s.cnt  = 0x%lx\n", name, type->cnt);
900 
901 	for (i = 0; i < type->cnt; i++) {
902 		struct memblock_region *rgn = &type->regions[i];
903 		char nid_buf[32] = "";
904 
905 		base = rgn->base;
906 		size = rgn->size;
907 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
908 		if (memblock_get_region_node(rgn) != MAX_NUMNODES)
909 			snprintf(nid_buf, sizeof(nid_buf), " on node %d",
910 				 memblock_get_region_node(rgn));
911 #endif
912 		pr_info(" %s[%#x]\t[%#016llx-%#016llx], %#llx bytes%s\n",
913 			name, i, base, base + size - 1, size, nid_buf);
914 	}
915 }
916 
917 void __init_memblock __memblock_dump_all(void)
918 {
919 	pr_info("MEMBLOCK configuration:\n");
920 	pr_info(" memory size = %#llx reserved size = %#llx\n",
921 		(unsigned long long)memblock.memory.total_size,
922 		(unsigned long long)memblock.reserved.total_size);
923 
924 	memblock_dump(&memblock.memory, "memory");
925 	memblock_dump(&memblock.reserved, "reserved");
926 }
927 
928 void __init memblock_allow_resize(void)
929 {
930 	memblock_can_resize = 1;
931 }
932 
933 static int __init early_memblock(char *p)
934 {
935 	if (p && strstr(p, "debug"))
936 		memblock_debug = 1;
937 	return 0;
938 }
939 early_param("memblock", early_memblock);
940 
941 #if defined(CONFIG_DEBUG_FS) && !defined(CONFIG_ARCH_DISCARD_MEMBLOCK)
942 
943 static int memblock_debug_show(struct seq_file *m, void *private)
944 {
945 	struct memblock_type *type = m->private;
946 	struct memblock_region *reg;
947 	int i;
948 
949 	for (i = 0; i < type->cnt; i++) {
950 		reg = &type->regions[i];
951 		seq_printf(m, "%4d: ", i);
952 		if (sizeof(phys_addr_t) == 4)
953 			seq_printf(m, "0x%08lx..0x%08lx\n",
954 				   (unsigned long)reg->base,
955 				   (unsigned long)(reg->base + reg->size - 1));
956 		else
957 			seq_printf(m, "0x%016llx..0x%016llx\n",
958 				   (unsigned long long)reg->base,
959 				   (unsigned long long)(reg->base + reg->size - 1));
960 
961 	}
962 	return 0;
963 }
964 
965 static int memblock_debug_open(struct inode *inode, struct file *file)
966 {
967 	return single_open(file, memblock_debug_show, inode->i_private);
968 }
969 
970 static const struct file_operations memblock_debug_fops = {
971 	.open = memblock_debug_open,
972 	.read = seq_read,
973 	.llseek = seq_lseek,
974 	.release = single_release,
975 };
976 
977 static int __init memblock_init_debugfs(void)
978 {
979 	struct dentry *root = debugfs_create_dir("memblock", NULL);
980 	if (!root)
981 		return -ENXIO;
982 	debugfs_create_file("memory", S_IRUGO, root, &memblock.memory, &memblock_debug_fops);
983 	debugfs_create_file("reserved", S_IRUGO, root, &memblock.reserved, &memblock_debug_fops);
984 
985 	return 0;
986 }
987 __initcall(memblock_init_debugfs);
988 
989 #endif /* CONFIG_DEBUG_FS */
990