xref: /openbmc/linux/mm/memblock.c (revision cd5d5810)
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 __init_memblock const char *
45 memblock_type_name(struct memblock_type *type)
46 {
47 	if (type == &memblock.memory)
48 		return "memory";
49 	else if (type == &memblock.reserved)
50 		return "reserved";
51 	else
52 		return "unknown";
53 }
54 
55 /* adjust *@size so that (@base + *@size) doesn't overflow, return new size */
56 static inline phys_addr_t memblock_cap_size(phys_addr_t base, phys_addr_t *size)
57 {
58 	return *size = min(*size, (phys_addr_t)ULLONG_MAX - base);
59 }
60 
61 /*
62  * Address comparison utilities
63  */
64 static unsigned long __init_memblock memblock_addrs_overlap(phys_addr_t base1, phys_addr_t size1,
65 				       phys_addr_t base2, phys_addr_t size2)
66 {
67 	return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
68 }
69 
70 static long __init_memblock memblock_overlaps_region(struct memblock_type *type,
71 					phys_addr_t base, phys_addr_t size)
72 {
73 	unsigned long i;
74 
75 	for (i = 0; i < type->cnt; i++) {
76 		phys_addr_t rgnbase = type->regions[i].base;
77 		phys_addr_t rgnsize = type->regions[i].size;
78 		if (memblock_addrs_overlap(base, size, rgnbase, rgnsize))
79 			break;
80 	}
81 
82 	return (i < type->cnt) ? i : -1;
83 }
84 
85 /**
86  * memblock_find_in_range_node - find free area in given range and node
87  * @start: start of candidate range
88  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_{ANYWHERE|ACCESSIBLE}
89  * @size: size of free area to find
90  * @align: alignment of free area to find
91  * @nid: nid of the free area to find, %MAX_NUMNODES for any node
92  *
93  * Find @size free area aligned to @align in the specified range and node.
94  *
95  * RETURNS:
96  * Found address on success, %0 on failure.
97  */
98 phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t start,
99 					phys_addr_t end, phys_addr_t size,
100 					phys_addr_t align, int nid)
101 {
102 	phys_addr_t this_start, this_end, cand;
103 	u64 i;
104 
105 	/* pump up @end */
106 	if (end == MEMBLOCK_ALLOC_ACCESSIBLE)
107 		end = memblock.current_limit;
108 
109 	/* avoid allocating the first page */
110 	start = max_t(phys_addr_t, start, PAGE_SIZE);
111 	end = max(start, end);
112 
113 	for_each_free_mem_range_reverse(i, nid, &this_start, &this_end, NULL) {
114 		this_start = clamp(this_start, start, end);
115 		this_end = clamp(this_end, start, end);
116 
117 		if (this_end < size)
118 			continue;
119 
120 		cand = round_down(this_end - size, align);
121 		if (cand >= this_start)
122 			return cand;
123 	}
124 	return 0;
125 }
126 
127 /**
128  * memblock_find_in_range - find free area in given range
129  * @start: start of candidate range
130  * @end: end of candidate range, can be %MEMBLOCK_ALLOC_{ANYWHERE|ACCESSIBLE}
131  * @size: size of free area to find
132  * @align: alignment of free area to find
133  *
134  * Find @size free area aligned to @align in the specified range.
135  *
136  * RETURNS:
137  * Found address on success, %0 on failure.
138  */
139 phys_addr_t __init_memblock memblock_find_in_range(phys_addr_t start,
140 					phys_addr_t end, phys_addr_t size,
141 					phys_addr_t align)
142 {
143 	return memblock_find_in_range_node(start, end, size, align,
144 					   MAX_NUMNODES);
145 }
146 
147 static void __init_memblock memblock_remove_region(struct memblock_type *type, unsigned long r)
148 {
149 	type->total_size -= type->regions[r].size;
150 	memmove(&type->regions[r], &type->regions[r + 1],
151 		(type->cnt - (r + 1)) * sizeof(type->regions[r]));
152 	type->cnt--;
153 
154 	/* Special case for empty arrays */
155 	if (type->cnt == 0) {
156 		WARN_ON(type->total_size != 0);
157 		type->cnt = 1;
158 		type->regions[0].base = 0;
159 		type->regions[0].size = 0;
160 		memblock_set_region_node(&type->regions[0], MAX_NUMNODES);
161 	}
162 }
163 
164 phys_addr_t __init_memblock get_allocated_memblock_reserved_regions_info(
165 					phys_addr_t *addr)
166 {
167 	if (memblock.reserved.regions == memblock_reserved_init_regions)
168 		return 0;
169 
170 	*addr = __pa(memblock.reserved.regions);
171 
172 	return PAGE_ALIGN(sizeof(struct memblock_region) *
173 			  memblock.reserved.max);
174 }
175 
176 /**
177  * memblock_double_array - double the size of the memblock regions array
178  * @type: memblock type of the regions array being doubled
179  * @new_area_start: starting address of memory range to avoid overlap with
180  * @new_area_size: size of memory range to avoid overlap with
181  *
182  * Double the size of the @type regions array. If memblock is being used to
183  * allocate memory for a new reserved regions array and there is a previously
184  * allocated memory range [@new_area_start,@new_area_start+@new_area_size]
185  * waiting to be reserved, ensure the memory used by the new array does
186  * not overlap.
187  *
188  * RETURNS:
189  * 0 on success, -1 on failure.
190  */
191 static int __init_memblock memblock_double_array(struct memblock_type *type,
192 						phys_addr_t new_area_start,
193 						phys_addr_t new_area_size)
194 {
195 	struct memblock_region *new_array, *old_array;
196 	phys_addr_t old_alloc_size, new_alloc_size;
197 	phys_addr_t old_size, new_size, addr;
198 	int use_slab = slab_is_available();
199 	int *in_slab;
200 
201 	/* We don't allow resizing until we know about the reserved regions
202 	 * of memory that aren't suitable for allocation
203 	 */
204 	if (!memblock_can_resize)
205 		return -1;
206 
207 	/* Calculate new doubled size */
208 	old_size = type->max * sizeof(struct memblock_region);
209 	new_size = old_size << 1;
210 	/*
211 	 * We need to allocated new one align to PAGE_SIZE,
212 	 *   so we can free them completely later.
213 	 */
214 	old_alloc_size = PAGE_ALIGN(old_size);
215 	new_alloc_size = PAGE_ALIGN(new_size);
216 
217 	/* Retrieve the slab flag */
218 	if (type == &memblock.memory)
219 		in_slab = &memblock_memory_in_slab;
220 	else
221 		in_slab = &memblock_reserved_in_slab;
222 
223 	/* Try to find some space for it.
224 	 *
225 	 * WARNING: We assume that either slab_is_available() and we use it or
226 	 * we use MEMBLOCK for allocations. That means that this is unsafe to
227 	 * use when bootmem is currently active (unless bootmem itself is
228 	 * implemented on top of MEMBLOCK which isn't the case yet)
229 	 *
230 	 * This should however not be an issue for now, as we currently only
231 	 * call into MEMBLOCK while it's still active, or much later when slab
232 	 * is active for memory hotplug operations
233 	 */
234 	if (use_slab) {
235 		new_array = kmalloc(new_size, GFP_KERNEL);
236 		addr = new_array ? __pa(new_array) : 0;
237 	} else {
238 		/* only exclude range when trying to double reserved.regions */
239 		if (type != &memblock.reserved)
240 			new_area_start = new_area_size = 0;
241 
242 		addr = memblock_find_in_range(new_area_start + new_area_size,
243 						memblock.current_limit,
244 						new_alloc_size, PAGE_SIZE);
245 		if (!addr && new_area_size)
246 			addr = memblock_find_in_range(0,
247 				min(new_area_start, memblock.current_limit),
248 				new_alloc_size, PAGE_SIZE);
249 
250 		new_array = addr ? __va(addr) : NULL;
251 	}
252 	if (!addr) {
253 		pr_err("memblock: Failed to double %s array from %ld to %ld entries !\n",
254 		       memblock_type_name(type), type->max, type->max * 2);
255 		return -1;
256 	}
257 
258 	memblock_dbg("memblock: %s is doubled to %ld at [%#010llx-%#010llx]",
259 			memblock_type_name(type), type->max * 2, (u64)addr,
260 			(u64)addr + new_size - 1);
261 
262 	/*
263 	 * Found space, we now need to move the array over before we add the
264 	 * reserved region since it may be our reserved array itself that is
265 	 * full.
266 	 */
267 	memcpy(new_array, type->regions, old_size);
268 	memset(new_array + type->max, 0, old_size);
269 	old_array = type->regions;
270 	type->regions = new_array;
271 	type->max <<= 1;
272 
273 	/* Free old array. We needn't free it if the array is the static one */
274 	if (*in_slab)
275 		kfree(old_array);
276 	else if (old_array != memblock_memory_init_regions &&
277 		 old_array != memblock_reserved_init_regions)
278 		memblock_free(__pa(old_array), old_alloc_size);
279 
280 	/*
281 	 * Reserve the new array if that comes from the memblock.  Otherwise, we
282 	 * needn't do it
283 	 */
284 	if (!use_slab)
285 		BUG_ON(memblock_reserve(addr, new_alloc_size));
286 
287 	/* Update slab flag */
288 	*in_slab = use_slab;
289 
290 	return 0;
291 }
292 
293 /**
294  * memblock_merge_regions - merge neighboring compatible regions
295  * @type: memblock type to scan
296  *
297  * Scan @type and merge neighboring compatible regions.
298  */
299 static void __init_memblock memblock_merge_regions(struct memblock_type *type)
300 {
301 	int i = 0;
302 
303 	/* cnt never goes below 1 */
304 	while (i < type->cnt - 1) {
305 		struct memblock_region *this = &type->regions[i];
306 		struct memblock_region *next = &type->regions[i + 1];
307 
308 		if (this->base + this->size != next->base ||
309 		    memblock_get_region_node(this) !=
310 		    memblock_get_region_node(next)) {
311 			BUG_ON(this->base + this->size > next->base);
312 			i++;
313 			continue;
314 		}
315 
316 		this->size += next->size;
317 		/* move forward from next + 1, index of which is i + 2 */
318 		memmove(next, next + 1, (type->cnt - (i + 2)) * sizeof(*next));
319 		type->cnt--;
320 	}
321 }
322 
323 /**
324  * memblock_insert_region - insert new memblock region
325  * @type:	memblock type to insert into
326  * @idx:	index for the insertion point
327  * @base:	base address of the new region
328  * @size:	size of the new region
329  * @nid:	node id of the new region
330  *
331  * Insert new memblock region [@base,@base+@size) into @type at @idx.
332  * @type must already have extra room to accomodate the new region.
333  */
334 static void __init_memblock memblock_insert_region(struct memblock_type *type,
335 						   int idx, phys_addr_t base,
336 						   phys_addr_t size, int nid)
337 {
338 	struct memblock_region *rgn = &type->regions[idx];
339 
340 	BUG_ON(type->cnt >= type->max);
341 	memmove(rgn + 1, rgn, (type->cnt - idx) * sizeof(*rgn));
342 	rgn->base = base;
343 	rgn->size = size;
344 	memblock_set_region_node(rgn, nid);
345 	type->cnt++;
346 	type->total_size += size;
347 }
348 
349 /**
350  * memblock_add_region - add new memblock region
351  * @type: memblock type to add new region into
352  * @base: base address of the new region
353  * @size: size of the new region
354  * @nid: nid of the new region
355  *
356  * Add new memblock region [@base,@base+@size) into @type.  The new region
357  * is allowed to overlap with existing ones - overlaps don't affect already
358  * existing regions.  @type is guaranteed to be minimal (all neighbouring
359  * compatible regions are merged) after the addition.
360  *
361  * RETURNS:
362  * 0 on success, -errno on failure.
363  */
364 static int __init_memblock memblock_add_region(struct memblock_type *type,
365 				phys_addr_t base, phys_addr_t size, int nid)
366 {
367 	bool insert = false;
368 	phys_addr_t obase = base;
369 	phys_addr_t end = base + memblock_cap_size(base, &size);
370 	int i, nr_new;
371 
372 	if (!size)
373 		return 0;
374 
375 	/* special case for empty array */
376 	if (type->regions[0].size == 0) {
377 		WARN_ON(type->cnt != 1 || type->total_size);
378 		type->regions[0].base = base;
379 		type->regions[0].size = size;
380 		memblock_set_region_node(&type->regions[0], nid);
381 		type->total_size = size;
382 		return 0;
383 	}
384 repeat:
385 	/*
386 	 * The following is executed twice.  Once with %false @insert and
387 	 * then with %true.  The first counts the number of regions needed
388 	 * to accomodate the new area.  The second actually inserts them.
389 	 */
390 	base = obase;
391 	nr_new = 0;
392 
393 	for (i = 0; i < type->cnt; i++) {
394 		struct memblock_region *rgn = &type->regions[i];
395 		phys_addr_t rbase = rgn->base;
396 		phys_addr_t rend = rbase + rgn->size;
397 
398 		if (rbase >= end)
399 			break;
400 		if (rend <= base)
401 			continue;
402 		/*
403 		 * @rgn overlaps.  If it separates the lower part of new
404 		 * area, insert that portion.
405 		 */
406 		if (rbase > base) {
407 			nr_new++;
408 			if (insert)
409 				memblock_insert_region(type, i++, base,
410 						       rbase - base, nid);
411 		}
412 		/* area below @rend is dealt with, forget about it */
413 		base = min(rend, end);
414 	}
415 
416 	/* insert the remaining portion */
417 	if (base < end) {
418 		nr_new++;
419 		if (insert)
420 			memblock_insert_region(type, i, base, end - base, nid);
421 	}
422 
423 	/*
424 	 * If this was the first round, resize array and repeat for actual
425 	 * insertions; otherwise, merge and return.
426 	 */
427 	if (!insert) {
428 		while (type->cnt + nr_new > type->max)
429 			if (memblock_double_array(type, obase, size) < 0)
430 				return -ENOMEM;
431 		insert = true;
432 		goto repeat;
433 	} else {
434 		memblock_merge_regions(type);
435 		return 0;
436 	}
437 }
438 
439 int __init_memblock memblock_add_node(phys_addr_t base, phys_addr_t size,
440 				       int nid)
441 {
442 	return memblock_add_region(&memblock.memory, base, size, nid);
443 }
444 
445 int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
446 {
447 	return memblock_add_region(&memblock.memory, base, size, MAX_NUMNODES);
448 }
449 
450 /**
451  * memblock_isolate_range - isolate given range into disjoint memblocks
452  * @type: memblock type to isolate range for
453  * @base: base of range to isolate
454  * @size: size of range to isolate
455  * @start_rgn: out parameter for the start of isolated region
456  * @end_rgn: out parameter for the end of isolated region
457  *
458  * Walk @type and ensure that regions don't cross the boundaries defined by
459  * [@base,@base+@size).  Crossing regions are split at the boundaries,
460  * which may create at most two more regions.  The index of the first
461  * region inside the range is returned in *@start_rgn and end in *@end_rgn.
462  *
463  * RETURNS:
464  * 0 on success, -errno on failure.
465  */
466 static int __init_memblock memblock_isolate_range(struct memblock_type *type,
467 					phys_addr_t base, phys_addr_t size,
468 					int *start_rgn, int *end_rgn)
469 {
470 	phys_addr_t end = base + memblock_cap_size(base, &size);
471 	int i;
472 
473 	*start_rgn = *end_rgn = 0;
474 
475 	if (!size)
476 		return 0;
477 
478 	/* we'll create at most two more regions */
479 	while (type->cnt + 2 > type->max)
480 		if (memblock_double_array(type, base, size) < 0)
481 			return -ENOMEM;
482 
483 	for (i = 0; i < type->cnt; i++) {
484 		struct memblock_region *rgn = &type->regions[i];
485 		phys_addr_t rbase = rgn->base;
486 		phys_addr_t rend = rbase + rgn->size;
487 
488 		if (rbase >= end)
489 			break;
490 		if (rend <= base)
491 			continue;
492 
493 		if (rbase < base) {
494 			/*
495 			 * @rgn intersects from below.  Split and continue
496 			 * to process the next region - the new top half.
497 			 */
498 			rgn->base = base;
499 			rgn->size -= base - rbase;
500 			type->total_size -= base - rbase;
501 			memblock_insert_region(type, i, rbase, base - rbase,
502 					       memblock_get_region_node(rgn));
503 		} else if (rend > end) {
504 			/*
505 			 * @rgn intersects from above.  Split and redo the
506 			 * current region - the new bottom half.
507 			 */
508 			rgn->base = end;
509 			rgn->size -= end - rbase;
510 			type->total_size -= end - rbase;
511 			memblock_insert_region(type, i--, rbase, end - rbase,
512 					       memblock_get_region_node(rgn));
513 		} else {
514 			/* @rgn is fully contained, record it */
515 			if (!*end_rgn)
516 				*start_rgn = i;
517 			*end_rgn = i + 1;
518 		}
519 	}
520 
521 	return 0;
522 }
523 
524 static int __init_memblock __memblock_remove(struct memblock_type *type,
525 					     phys_addr_t base, phys_addr_t size)
526 {
527 	int start_rgn, end_rgn;
528 	int i, ret;
529 
530 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
531 	if (ret)
532 		return ret;
533 
534 	for (i = end_rgn - 1; i >= start_rgn; i--)
535 		memblock_remove_region(type, i);
536 	return 0;
537 }
538 
539 int __init_memblock memblock_remove(phys_addr_t base, phys_addr_t size)
540 {
541 	return __memblock_remove(&memblock.memory, base, size);
542 }
543 
544 int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)
545 {
546 	memblock_dbg("   memblock_free: [%#016llx-%#016llx] %pF\n",
547 		     (unsigned long long)base,
548 		     (unsigned long long)base + size,
549 		     (void *)_RET_IP_);
550 
551 	return __memblock_remove(&memblock.reserved, base, size);
552 }
553 
554 int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
555 {
556 	struct memblock_type *_rgn = &memblock.reserved;
557 
558 	memblock_dbg("memblock_reserve: [%#016llx-%#016llx] %pF\n",
559 		     (unsigned long long)base,
560 		     (unsigned long long)base + size,
561 		     (void *)_RET_IP_);
562 
563 	return memblock_add_region(_rgn, base, size, MAX_NUMNODES);
564 }
565 
566 /**
567  * __next_free_mem_range - next function for for_each_free_mem_range()
568  * @idx: pointer to u64 loop variable
569  * @nid: node selector, %MAX_NUMNODES for all nodes
570  * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
571  * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
572  * @out_nid: ptr to int for nid of the range, can be %NULL
573  *
574  * Find the first free area from *@idx which matches @nid, fill the out
575  * parameters, and update *@idx for the next iteration.  The lower 32bit of
576  * *@idx contains index into memory region and the upper 32bit indexes the
577  * areas before each reserved region.  For example, if reserved regions
578  * look like the following,
579  *
580  *	0:[0-16), 1:[32-48), 2:[128-130)
581  *
582  * The upper 32bit indexes the following regions.
583  *
584  *	0:[0-0), 1:[16-32), 2:[48-128), 3:[130-MAX)
585  *
586  * As both region arrays are sorted, the function advances the two indices
587  * in lockstep and returns each intersection.
588  */
589 void __init_memblock __next_free_mem_range(u64 *idx, int nid,
590 					   phys_addr_t *out_start,
591 					   phys_addr_t *out_end, int *out_nid)
592 {
593 	struct memblock_type *mem = &memblock.memory;
594 	struct memblock_type *rsv = &memblock.reserved;
595 	int mi = *idx & 0xffffffff;
596 	int ri = *idx >> 32;
597 
598 	for ( ; mi < mem->cnt; mi++) {
599 		struct memblock_region *m = &mem->regions[mi];
600 		phys_addr_t m_start = m->base;
601 		phys_addr_t m_end = m->base + m->size;
602 
603 		/* only memory regions are associated with nodes, check it */
604 		if (nid != MAX_NUMNODES && nid != memblock_get_region_node(m))
605 			continue;
606 
607 		/* scan areas before each reservation for intersection */
608 		for ( ; ri < rsv->cnt + 1; ri++) {
609 			struct memblock_region *r = &rsv->regions[ri];
610 			phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
611 			phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
612 
613 			/* if ri advanced past mi, break out to advance mi */
614 			if (r_start >= m_end)
615 				break;
616 			/* if the two regions intersect, we're done */
617 			if (m_start < r_end) {
618 				if (out_start)
619 					*out_start = max(m_start, r_start);
620 				if (out_end)
621 					*out_end = min(m_end, r_end);
622 				if (out_nid)
623 					*out_nid = memblock_get_region_node(m);
624 				/*
625 				 * The region which ends first is advanced
626 				 * for the next iteration.
627 				 */
628 				if (m_end <= r_end)
629 					mi++;
630 				else
631 					ri++;
632 				*idx = (u32)mi | (u64)ri << 32;
633 				return;
634 			}
635 		}
636 	}
637 
638 	/* signal end of iteration */
639 	*idx = ULLONG_MAX;
640 }
641 
642 /**
643  * __next_free_mem_range_rev - next function for for_each_free_mem_range_reverse()
644  * @idx: pointer to u64 loop variable
645  * @nid: nid: node selector, %MAX_NUMNODES for all nodes
646  * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
647  * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
648  * @out_nid: ptr to int for nid of the range, can be %NULL
649  *
650  * Reverse of __next_free_mem_range().
651  */
652 void __init_memblock __next_free_mem_range_rev(u64 *idx, int nid,
653 					   phys_addr_t *out_start,
654 					   phys_addr_t *out_end, int *out_nid)
655 {
656 	struct memblock_type *mem = &memblock.memory;
657 	struct memblock_type *rsv = &memblock.reserved;
658 	int mi = *idx & 0xffffffff;
659 	int ri = *idx >> 32;
660 
661 	if (*idx == (u64)ULLONG_MAX) {
662 		mi = mem->cnt - 1;
663 		ri = rsv->cnt;
664 	}
665 
666 	for ( ; mi >= 0; mi--) {
667 		struct memblock_region *m = &mem->regions[mi];
668 		phys_addr_t m_start = m->base;
669 		phys_addr_t m_end = m->base + m->size;
670 
671 		/* only memory regions are associated with nodes, check it */
672 		if (nid != MAX_NUMNODES && nid != memblock_get_region_node(m))
673 			continue;
674 
675 		/* scan areas before each reservation for intersection */
676 		for ( ; ri >= 0; ri--) {
677 			struct memblock_region *r = &rsv->regions[ri];
678 			phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
679 			phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
680 
681 			/* if ri advanced past mi, break out to advance mi */
682 			if (r_end <= m_start)
683 				break;
684 			/* if the two regions intersect, we're done */
685 			if (m_end > r_start) {
686 				if (out_start)
687 					*out_start = max(m_start, r_start);
688 				if (out_end)
689 					*out_end = min(m_end, r_end);
690 				if (out_nid)
691 					*out_nid = memblock_get_region_node(m);
692 
693 				if (m_start >= r_start)
694 					mi--;
695 				else
696 					ri--;
697 				*idx = (u32)mi | (u64)ri << 32;
698 				return;
699 			}
700 		}
701 	}
702 
703 	*idx = ULLONG_MAX;
704 }
705 
706 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
707 /*
708  * Common iterator interface used to define for_each_mem_range().
709  */
710 void __init_memblock __next_mem_pfn_range(int *idx, int nid,
711 				unsigned long *out_start_pfn,
712 				unsigned long *out_end_pfn, int *out_nid)
713 {
714 	struct memblock_type *type = &memblock.memory;
715 	struct memblock_region *r;
716 
717 	while (++*idx < type->cnt) {
718 		r = &type->regions[*idx];
719 
720 		if (PFN_UP(r->base) >= PFN_DOWN(r->base + r->size))
721 			continue;
722 		if (nid == MAX_NUMNODES || nid == r->nid)
723 			break;
724 	}
725 	if (*idx >= type->cnt) {
726 		*idx = -1;
727 		return;
728 	}
729 
730 	if (out_start_pfn)
731 		*out_start_pfn = PFN_UP(r->base);
732 	if (out_end_pfn)
733 		*out_end_pfn = PFN_DOWN(r->base + r->size);
734 	if (out_nid)
735 		*out_nid = r->nid;
736 }
737 
738 /**
739  * memblock_set_node - set node ID on memblock regions
740  * @base: base of area to set node ID for
741  * @size: size of area to set node ID for
742  * @nid: node ID to set
743  *
744  * Set the nid of memblock memory regions in [@base,@base+@size) to @nid.
745  * Regions which cross the area boundaries are split as necessary.
746  *
747  * RETURNS:
748  * 0 on success, -errno on failure.
749  */
750 int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
751 				      int nid)
752 {
753 	struct memblock_type *type = &memblock.memory;
754 	int start_rgn, end_rgn;
755 	int i, ret;
756 
757 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
758 	if (ret)
759 		return ret;
760 
761 	for (i = start_rgn; i < end_rgn; i++)
762 		memblock_set_region_node(&type->regions[i], nid);
763 
764 	memblock_merge_regions(type);
765 	return 0;
766 }
767 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
768 
769 static phys_addr_t __init memblock_alloc_base_nid(phys_addr_t size,
770 					phys_addr_t align, phys_addr_t max_addr,
771 					int nid)
772 {
773 	phys_addr_t found;
774 
775 	if (WARN_ON(!align))
776 		align = __alignof__(long long);
777 
778 	/* align @size to avoid excessive fragmentation on reserved array */
779 	size = round_up(size, align);
780 
781 	found = memblock_find_in_range_node(0, max_addr, size, align, nid);
782 	if (found && !memblock_reserve(found, size))
783 		return found;
784 
785 	return 0;
786 }
787 
788 phys_addr_t __init memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int nid)
789 {
790 	return memblock_alloc_base_nid(size, align, MEMBLOCK_ALLOC_ACCESSIBLE, nid);
791 }
792 
793 phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
794 {
795 	return memblock_alloc_base_nid(size, align, max_addr, MAX_NUMNODES);
796 }
797 
798 phys_addr_t __init memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
799 {
800 	phys_addr_t alloc;
801 
802 	alloc = __memblock_alloc_base(size, align, max_addr);
803 
804 	if (alloc == 0)
805 		panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
806 		      (unsigned long long) size, (unsigned long long) max_addr);
807 
808 	return alloc;
809 }
810 
811 phys_addr_t __init memblock_alloc(phys_addr_t size, phys_addr_t align)
812 {
813 	return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
814 }
815 
816 phys_addr_t __init memblock_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
817 {
818 	phys_addr_t res = memblock_alloc_nid(size, align, nid);
819 
820 	if (res)
821 		return res;
822 	return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
823 }
824 
825 
826 /*
827  * Remaining API functions
828  */
829 
830 phys_addr_t __init memblock_phys_mem_size(void)
831 {
832 	return memblock.memory.total_size;
833 }
834 
835 phys_addr_t __init memblock_mem_size(unsigned long limit_pfn)
836 {
837 	unsigned long pages = 0;
838 	struct memblock_region *r;
839 	unsigned long start_pfn, end_pfn;
840 
841 	for_each_memblock(memory, r) {
842 		start_pfn = memblock_region_memory_base_pfn(r);
843 		end_pfn = memblock_region_memory_end_pfn(r);
844 		start_pfn = min_t(unsigned long, start_pfn, limit_pfn);
845 		end_pfn = min_t(unsigned long, end_pfn, limit_pfn);
846 		pages += end_pfn - start_pfn;
847 	}
848 
849 	return (phys_addr_t)pages << PAGE_SHIFT;
850 }
851 
852 /* lowest address */
853 phys_addr_t __init_memblock memblock_start_of_DRAM(void)
854 {
855 	return memblock.memory.regions[0].base;
856 }
857 
858 phys_addr_t __init_memblock memblock_end_of_DRAM(void)
859 {
860 	int idx = memblock.memory.cnt - 1;
861 
862 	return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
863 }
864 
865 void __init memblock_enforce_memory_limit(phys_addr_t limit)
866 {
867 	unsigned long i;
868 	phys_addr_t max_addr = (phys_addr_t)ULLONG_MAX;
869 
870 	if (!limit)
871 		return;
872 
873 	/* find out max address */
874 	for (i = 0; i < memblock.memory.cnt; i++) {
875 		struct memblock_region *r = &memblock.memory.regions[i];
876 
877 		if (limit <= r->size) {
878 			max_addr = r->base + limit;
879 			break;
880 		}
881 		limit -= r->size;
882 	}
883 
884 	/* truncate both memory and reserved regions */
885 	__memblock_remove(&memblock.memory, max_addr, (phys_addr_t)ULLONG_MAX);
886 	__memblock_remove(&memblock.reserved, max_addr, (phys_addr_t)ULLONG_MAX);
887 }
888 
889 static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
890 {
891 	unsigned int left = 0, right = type->cnt;
892 
893 	do {
894 		unsigned int mid = (right + left) / 2;
895 
896 		if (addr < type->regions[mid].base)
897 			right = mid;
898 		else if (addr >= (type->regions[mid].base +
899 				  type->regions[mid].size))
900 			left = mid + 1;
901 		else
902 			return mid;
903 	} while (left < right);
904 	return -1;
905 }
906 
907 int __init memblock_is_reserved(phys_addr_t addr)
908 {
909 	return memblock_search(&memblock.reserved, addr) != -1;
910 }
911 
912 int __init_memblock memblock_is_memory(phys_addr_t addr)
913 {
914 	return memblock_search(&memblock.memory, addr) != -1;
915 }
916 
917 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
918 int __init_memblock memblock_search_pfn_nid(unsigned long pfn,
919 			 unsigned long *start_pfn, unsigned long *end_pfn)
920 {
921 	struct memblock_type *type = &memblock.memory;
922 	int mid = memblock_search(type, (phys_addr_t)pfn << PAGE_SHIFT);
923 
924 	if (mid == -1)
925 		return -1;
926 
927 	*start_pfn = type->regions[mid].base >> PAGE_SHIFT;
928 	*end_pfn = (type->regions[mid].base + type->regions[mid].size)
929 			>> PAGE_SHIFT;
930 
931 	return type->regions[mid].nid;
932 }
933 #endif
934 
935 /**
936  * memblock_is_region_memory - check if a region is a subset of memory
937  * @base: base of region to check
938  * @size: size of region to check
939  *
940  * Check if the region [@base, @base+@size) is a subset of a memory block.
941  *
942  * RETURNS:
943  * 0 if false, non-zero if true
944  */
945 int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
946 {
947 	int idx = memblock_search(&memblock.memory, base);
948 	phys_addr_t end = base + memblock_cap_size(base, &size);
949 
950 	if (idx == -1)
951 		return 0;
952 	return memblock.memory.regions[idx].base <= base &&
953 		(memblock.memory.regions[idx].base +
954 		 memblock.memory.regions[idx].size) >= end;
955 }
956 
957 /**
958  * memblock_is_region_reserved - check if a region intersects reserved memory
959  * @base: base of region to check
960  * @size: size of region to check
961  *
962  * Check if the region [@base, @base+@size) intersects a reserved memory block.
963  *
964  * RETURNS:
965  * 0 if false, non-zero if true
966  */
967 int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
968 {
969 	memblock_cap_size(base, &size);
970 	return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;
971 }
972 
973 void __init_memblock memblock_trim_memory(phys_addr_t align)
974 {
975 	int i;
976 	phys_addr_t start, end, orig_start, orig_end;
977 	struct memblock_type *mem = &memblock.memory;
978 
979 	for (i = 0; i < mem->cnt; i++) {
980 		orig_start = mem->regions[i].base;
981 		orig_end = mem->regions[i].base + mem->regions[i].size;
982 		start = round_up(orig_start, align);
983 		end = round_down(orig_end, align);
984 
985 		if (start == orig_start && end == orig_end)
986 			continue;
987 
988 		if (start < end) {
989 			mem->regions[i].base = start;
990 			mem->regions[i].size = end - start;
991 		} else {
992 			memblock_remove_region(mem, i);
993 			i--;
994 		}
995 	}
996 }
997 
998 void __init_memblock memblock_set_current_limit(phys_addr_t limit)
999 {
1000 	memblock.current_limit = limit;
1001 }
1002 
1003 static void __init_memblock memblock_dump(struct memblock_type *type, char *name)
1004 {
1005 	unsigned long long base, size;
1006 	int i;
1007 
1008 	pr_info(" %s.cnt  = 0x%lx\n", name, type->cnt);
1009 
1010 	for (i = 0; i < type->cnt; i++) {
1011 		struct memblock_region *rgn = &type->regions[i];
1012 		char nid_buf[32] = "";
1013 
1014 		base = rgn->base;
1015 		size = rgn->size;
1016 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
1017 		if (memblock_get_region_node(rgn) != MAX_NUMNODES)
1018 			snprintf(nid_buf, sizeof(nid_buf), " on node %d",
1019 				 memblock_get_region_node(rgn));
1020 #endif
1021 		pr_info(" %s[%#x]\t[%#016llx-%#016llx], %#llx bytes%s\n",
1022 			name, i, base, base + size - 1, size, nid_buf);
1023 	}
1024 }
1025 
1026 void __init_memblock __memblock_dump_all(void)
1027 {
1028 	pr_info("MEMBLOCK configuration:\n");
1029 	pr_info(" memory size = %#llx reserved size = %#llx\n",
1030 		(unsigned long long)memblock.memory.total_size,
1031 		(unsigned long long)memblock.reserved.total_size);
1032 
1033 	memblock_dump(&memblock.memory, "memory");
1034 	memblock_dump(&memblock.reserved, "reserved");
1035 }
1036 
1037 void __init memblock_allow_resize(void)
1038 {
1039 	memblock_can_resize = 1;
1040 }
1041 
1042 static int __init early_memblock(char *p)
1043 {
1044 	if (p && strstr(p, "debug"))
1045 		memblock_debug = 1;
1046 	return 0;
1047 }
1048 early_param("memblock", early_memblock);
1049 
1050 #if defined(CONFIG_DEBUG_FS) && !defined(CONFIG_ARCH_DISCARD_MEMBLOCK)
1051 
1052 static int memblock_debug_show(struct seq_file *m, void *private)
1053 {
1054 	struct memblock_type *type = m->private;
1055 	struct memblock_region *reg;
1056 	int i;
1057 
1058 	for (i = 0; i < type->cnt; i++) {
1059 		reg = &type->regions[i];
1060 		seq_printf(m, "%4d: ", i);
1061 		if (sizeof(phys_addr_t) == 4)
1062 			seq_printf(m, "0x%08lx..0x%08lx\n",
1063 				   (unsigned long)reg->base,
1064 				   (unsigned long)(reg->base + reg->size - 1));
1065 		else
1066 			seq_printf(m, "0x%016llx..0x%016llx\n",
1067 				   (unsigned long long)reg->base,
1068 				   (unsigned long long)(reg->base + reg->size - 1));
1069 
1070 	}
1071 	return 0;
1072 }
1073 
1074 static int memblock_debug_open(struct inode *inode, struct file *file)
1075 {
1076 	return single_open(file, memblock_debug_show, inode->i_private);
1077 }
1078 
1079 static const struct file_operations memblock_debug_fops = {
1080 	.open = memblock_debug_open,
1081 	.read = seq_read,
1082 	.llseek = seq_lseek,
1083 	.release = single_release,
1084 };
1085 
1086 static int __init memblock_init_debugfs(void)
1087 {
1088 	struct dentry *root = debugfs_create_dir("memblock", NULL);
1089 	if (!root)
1090 		return -ENXIO;
1091 	debugfs_create_file("memory", S_IRUGO, root, &memblock.memory, &memblock_debug_fops);
1092 	debugfs_create_file("reserved", S_IRUGO, root, &memblock.reserved, &memblock_debug_fops);
1093 
1094 	return 0;
1095 }
1096 __initcall(memblock_init_debugfs);
1097 
1098 #endif /* CONFIG_DEBUG_FS */
1099