xref: /openbmc/linux/mm/memblock.c (revision d0b73b48)
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  *
330  * Insert new memblock region [@base,@base+@size) into @type at @idx.
331  * @type must already have extra room to accomodate the new region.
332  */
333 static void __init_memblock memblock_insert_region(struct memblock_type *type,
334 						   int idx, phys_addr_t base,
335 						   phys_addr_t size, int nid)
336 {
337 	struct memblock_region *rgn = &type->regions[idx];
338 
339 	BUG_ON(type->cnt >= type->max);
340 	memmove(rgn + 1, rgn, (type->cnt - idx) * sizeof(*rgn));
341 	rgn->base = base;
342 	rgn->size = size;
343 	memblock_set_region_node(rgn, nid);
344 	type->cnt++;
345 	type->total_size += size;
346 }
347 
348 /**
349  * memblock_add_region - add new memblock region
350  * @type: memblock type to add new region into
351  * @base: base address of the new region
352  * @size: size of the new region
353  * @nid: nid of the new region
354  *
355  * Add new memblock region [@base,@base+@size) into @type.  The new region
356  * is allowed to overlap with existing ones - overlaps don't affect already
357  * existing regions.  @type is guaranteed to be minimal (all neighbouring
358  * compatible regions are merged) after the addition.
359  *
360  * RETURNS:
361  * 0 on success, -errno on failure.
362  */
363 static int __init_memblock memblock_add_region(struct memblock_type *type,
364 				phys_addr_t base, phys_addr_t size, int nid)
365 {
366 	bool insert = false;
367 	phys_addr_t obase = base;
368 	phys_addr_t end = base + memblock_cap_size(base, &size);
369 	int i, nr_new;
370 
371 	if (!size)
372 		return 0;
373 
374 	/* special case for empty array */
375 	if (type->regions[0].size == 0) {
376 		WARN_ON(type->cnt != 1 || type->total_size);
377 		type->regions[0].base = base;
378 		type->regions[0].size = size;
379 		memblock_set_region_node(&type->regions[0], nid);
380 		type->total_size = size;
381 		return 0;
382 	}
383 repeat:
384 	/*
385 	 * The following is executed twice.  Once with %false @insert and
386 	 * then with %true.  The first counts the number of regions needed
387 	 * to accomodate the new area.  The second actually inserts them.
388 	 */
389 	base = obase;
390 	nr_new = 0;
391 
392 	for (i = 0; i < type->cnt; i++) {
393 		struct memblock_region *rgn = &type->regions[i];
394 		phys_addr_t rbase = rgn->base;
395 		phys_addr_t rend = rbase + rgn->size;
396 
397 		if (rbase >= end)
398 			break;
399 		if (rend <= base)
400 			continue;
401 		/*
402 		 * @rgn overlaps.  If it separates the lower part of new
403 		 * area, insert that portion.
404 		 */
405 		if (rbase > base) {
406 			nr_new++;
407 			if (insert)
408 				memblock_insert_region(type, i++, base,
409 						       rbase - base, nid);
410 		}
411 		/* area below @rend is dealt with, forget about it */
412 		base = min(rend, end);
413 	}
414 
415 	/* insert the remaining portion */
416 	if (base < end) {
417 		nr_new++;
418 		if (insert)
419 			memblock_insert_region(type, i, base, end - base, nid);
420 	}
421 
422 	/*
423 	 * If this was the first round, resize array and repeat for actual
424 	 * insertions; otherwise, merge and return.
425 	 */
426 	if (!insert) {
427 		while (type->cnt + nr_new > type->max)
428 			if (memblock_double_array(type, obase, size) < 0)
429 				return -ENOMEM;
430 		insert = true;
431 		goto repeat;
432 	} else {
433 		memblock_merge_regions(type);
434 		return 0;
435 	}
436 }
437 
438 int __init_memblock memblock_add_node(phys_addr_t base, phys_addr_t size,
439 				       int nid)
440 {
441 	return memblock_add_region(&memblock.memory, base, size, nid);
442 }
443 
444 int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
445 {
446 	return memblock_add_region(&memblock.memory, base, size, MAX_NUMNODES);
447 }
448 
449 /**
450  * memblock_isolate_range - isolate given range into disjoint memblocks
451  * @type: memblock type to isolate range for
452  * @base: base of range to isolate
453  * @size: size of range to isolate
454  * @start_rgn: out parameter for the start of isolated region
455  * @end_rgn: out parameter for the end of isolated region
456  *
457  * Walk @type and ensure that regions don't cross the boundaries defined by
458  * [@base,@base+@size).  Crossing regions are split at the boundaries,
459  * which may create at most two more regions.  The index of the first
460  * region inside the range is returned in *@start_rgn and end in *@end_rgn.
461  *
462  * RETURNS:
463  * 0 on success, -errno on failure.
464  */
465 static int __init_memblock memblock_isolate_range(struct memblock_type *type,
466 					phys_addr_t base, phys_addr_t size,
467 					int *start_rgn, int *end_rgn)
468 {
469 	phys_addr_t end = base + memblock_cap_size(base, &size);
470 	int i;
471 
472 	*start_rgn = *end_rgn = 0;
473 
474 	if (!size)
475 		return 0;
476 
477 	/* we'll create at most two more regions */
478 	while (type->cnt + 2 > type->max)
479 		if (memblock_double_array(type, base, size) < 0)
480 			return -ENOMEM;
481 
482 	for (i = 0; i < type->cnt; i++) {
483 		struct memblock_region *rgn = &type->regions[i];
484 		phys_addr_t rbase = rgn->base;
485 		phys_addr_t rend = rbase + rgn->size;
486 
487 		if (rbase >= end)
488 			break;
489 		if (rend <= base)
490 			continue;
491 
492 		if (rbase < base) {
493 			/*
494 			 * @rgn intersects from below.  Split and continue
495 			 * to process the next region - the new top half.
496 			 */
497 			rgn->base = base;
498 			rgn->size -= base - rbase;
499 			type->total_size -= base - rbase;
500 			memblock_insert_region(type, i, rbase, base - rbase,
501 					       memblock_get_region_node(rgn));
502 		} else if (rend > end) {
503 			/*
504 			 * @rgn intersects from above.  Split and redo the
505 			 * current region - the new bottom half.
506 			 */
507 			rgn->base = end;
508 			rgn->size -= end - rbase;
509 			type->total_size -= end - rbase;
510 			memblock_insert_region(type, i--, rbase, end - rbase,
511 					       memblock_get_region_node(rgn));
512 		} else {
513 			/* @rgn is fully contained, record it */
514 			if (!*end_rgn)
515 				*start_rgn = i;
516 			*end_rgn = i + 1;
517 		}
518 	}
519 
520 	return 0;
521 }
522 
523 static int __init_memblock __memblock_remove(struct memblock_type *type,
524 					     phys_addr_t base, phys_addr_t size)
525 {
526 	int start_rgn, end_rgn;
527 	int i, ret;
528 
529 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
530 	if (ret)
531 		return ret;
532 
533 	for (i = end_rgn - 1; i >= start_rgn; i--)
534 		memblock_remove_region(type, i);
535 	return 0;
536 }
537 
538 int __init_memblock memblock_remove(phys_addr_t base, phys_addr_t size)
539 {
540 	return __memblock_remove(&memblock.memory, base, size);
541 }
542 
543 int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)
544 {
545 	memblock_dbg("   memblock_free: [%#016llx-%#016llx] %pF\n",
546 		     (unsigned long long)base,
547 		     (unsigned long long)base + size,
548 		     (void *)_RET_IP_);
549 
550 	return __memblock_remove(&memblock.reserved, base, size);
551 }
552 
553 int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
554 {
555 	struct memblock_type *_rgn = &memblock.reserved;
556 
557 	memblock_dbg("memblock_reserve: [%#016llx-%#016llx] %pF\n",
558 		     (unsigned long long)base,
559 		     (unsigned long long)base + size,
560 		     (void *)_RET_IP_);
561 
562 	return memblock_add_region(_rgn, base, size, MAX_NUMNODES);
563 }
564 
565 /**
566  * __next_free_mem_range - next function for for_each_free_mem_range()
567  * @idx: pointer to u64 loop variable
568  * @nid: nid: node selector, %MAX_NUMNODES for all nodes
569  * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
570  * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
571  * @out_nid: ptr to int for nid of the range, can be %NULL
572  *
573  * Find the first free area from *@idx which matches @nid, fill the out
574  * parameters, and update *@idx for the next iteration.  The lower 32bit of
575  * *@idx contains index into memory region and the upper 32bit indexes the
576  * areas before each reserved region.  For example, if reserved regions
577  * look like the following,
578  *
579  *	0:[0-16), 1:[32-48), 2:[128-130)
580  *
581  * The upper 32bit indexes the following regions.
582  *
583  *	0:[0-0), 1:[16-32), 2:[48-128), 3:[130-MAX)
584  *
585  * As both region arrays are sorted, the function advances the two indices
586  * in lockstep and returns each intersection.
587  */
588 void __init_memblock __next_free_mem_range(u64 *idx, int nid,
589 					   phys_addr_t *out_start,
590 					   phys_addr_t *out_end, int *out_nid)
591 {
592 	struct memblock_type *mem = &memblock.memory;
593 	struct memblock_type *rsv = &memblock.reserved;
594 	int mi = *idx & 0xffffffff;
595 	int ri = *idx >> 32;
596 
597 	for ( ; mi < mem->cnt; mi++) {
598 		struct memblock_region *m = &mem->regions[mi];
599 		phys_addr_t m_start = m->base;
600 		phys_addr_t m_end = m->base + m->size;
601 
602 		/* only memory regions are associated with nodes, check it */
603 		if (nid != MAX_NUMNODES && nid != memblock_get_region_node(m))
604 			continue;
605 
606 		/* scan areas before each reservation for intersection */
607 		for ( ; ri < rsv->cnt + 1; ri++) {
608 			struct memblock_region *r = &rsv->regions[ri];
609 			phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
610 			phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
611 
612 			/* if ri advanced past mi, break out to advance mi */
613 			if (r_start >= m_end)
614 				break;
615 			/* if the two regions intersect, we're done */
616 			if (m_start < r_end) {
617 				if (out_start)
618 					*out_start = max(m_start, r_start);
619 				if (out_end)
620 					*out_end = min(m_end, r_end);
621 				if (out_nid)
622 					*out_nid = memblock_get_region_node(m);
623 				/*
624 				 * The region which ends first is advanced
625 				 * for the next iteration.
626 				 */
627 				if (m_end <= r_end)
628 					mi++;
629 				else
630 					ri++;
631 				*idx = (u32)mi | (u64)ri << 32;
632 				return;
633 			}
634 		}
635 	}
636 
637 	/* signal end of iteration */
638 	*idx = ULLONG_MAX;
639 }
640 
641 /**
642  * __next_free_mem_range_rev - next function for for_each_free_mem_range_reverse()
643  * @idx: pointer to u64 loop variable
644  * @nid: nid: node selector, %MAX_NUMNODES for all nodes
645  * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
646  * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
647  * @out_nid: ptr to int for nid of the range, can be %NULL
648  *
649  * Reverse of __next_free_mem_range().
650  */
651 void __init_memblock __next_free_mem_range_rev(u64 *idx, int nid,
652 					   phys_addr_t *out_start,
653 					   phys_addr_t *out_end, int *out_nid)
654 {
655 	struct memblock_type *mem = &memblock.memory;
656 	struct memblock_type *rsv = &memblock.reserved;
657 	int mi = *idx & 0xffffffff;
658 	int ri = *idx >> 32;
659 
660 	if (*idx == (u64)ULLONG_MAX) {
661 		mi = mem->cnt - 1;
662 		ri = rsv->cnt;
663 	}
664 
665 	for ( ; mi >= 0; mi--) {
666 		struct memblock_region *m = &mem->regions[mi];
667 		phys_addr_t m_start = m->base;
668 		phys_addr_t m_end = m->base + m->size;
669 
670 		/* only memory regions are associated with nodes, check it */
671 		if (nid != MAX_NUMNODES && nid != memblock_get_region_node(m))
672 			continue;
673 
674 		/* scan areas before each reservation for intersection */
675 		for ( ; ri >= 0; ri--) {
676 			struct memblock_region *r = &rsv->regions[ri];
677 			phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
678 			phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
679 
680 			/* if ri advanced past mi, break out to advance mi */
681 			if (r_end <= m_start)
682 				break;
683 			/* if the two regions intersect, we're done */
684 			if (m_end > r_start) {
685 				if (out_start)
686 					*out_start = max(m_start, r_start);
687 				if (out_end)
688 					*out_end = min(m_end, r_end);
689 				if (out_nid)
690 					*out_nid = memblock_get_region_node(m);
691 
692 				if (m_start >= r_start)
693 					mi--;
694 				else
695 					ri--;
696 				*idx = (u32)mi | (u64)ri << 32;
697 				return;
698 			}
699 		}
700 	}
701 
702 	*idx = ULLONG_MAX;
703 }
704 
705 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
706 /*
707  * Common iterator interface used to define for_each_mem_range().
708  */
709 void __init_memblock __next_mem_pfn_range(int *idx, int nid,
710 				unsigned long *out_start_pfn,
711 				unsigned long *out_end_pfn, int *out_nid)
712 {
713 	struct memblock_type *type = &memblock.memory;
714 	struct memblock_region *r;
715 
716 	while (++*idx < type->cnt) {
717 		r = &type->regions[*idx];
718 
719 		if (PFN_UP(r->base) >= PFN_DOWN(r->base + r->size))
720 			continue;
721 		if (nid == MAX_NUMNODES || nid == r->nid)
722 			break;
723 	}
724 	if (*idx >= type->cnt) {
725 		*idx = -1;
726 		return;
727 	}
728 
729 	if (out_start_pfn)
730 		*out_start_pfn = PFN_UP(r->base);
731 	if (out_end_pfn)
732 		*out_end_pfn = PFN_DOWN(r->base + r->size);
733 	if (out_nid)
734 		*out_nid = r->nid;
735 }
736 
737 /**
738  * memblock_set_node - set node ID on memblock regions
739  * @base: base of area to set node ID for
740  * @size: size of area to set node ID for
741  * @nid: node ID to set
742  *
743  * Set the nid of memblock memory regions in [@base,@base+@size) to @nid.
744  * Regions which cross the area boundaries are split as necessary.
745  *
746  * RETURNS:
747  * 0 on success, -errno on failure.
748  */
749 int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
750 				      int nid)
751 {
752 	struct memblock_type *type = &memblock.memory;
753 	int start_rgn, end_rgn;
754 	int i, ret;
755 
756 	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
757 	if (ret)
758 		return ret;
759 
760 	for (i = start_rgn; i < end_rgn; i++)
761 		memblock_set_region_node(&type->regions[i], nid);
762 
763 	memblock_merge_regions(type);
764 	return 0;
765 }
766 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
767 
768 static phys_addr_t __init memblock_alloc_base_nid(phys_addr_t size,
769 					phys_addr_t align, phys_addr_t max_addr,
770 					int nid)
771 {
772 	phys_addr_t found;
773 
774 	/* align @size to avoid excessive fragmentation on reserved array */
775 	size = round_up(size, align);
776 
777 	found = memblock_find_in_range_node(0, max_addr, size, align, nid);
778 	if (found && !memblock_reserve(found, size))
779 		return found;
780 
781 	return 0;
782 }
783 
784 phys_addr_t __init memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int nid)
785 {
786 	return memblock_alloc_base_nid(size, align, MEMBLOCK_ALLOC_ACCESSIBLE, nid);
787 }
788 
789 phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
790 {
791 	return memblock_alloc_base_nid(size, align, max_addr, MAX_NUMNODES);
792 }
793 
794 phys_addr_t __init memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
795 {
796 	phys_addr_t alloc;
797 
798 	alloc = __memblock_alloc_base(size, align, max_addr);
799 
800 	if (alloc == 0)
801 		panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
802 		      (unsigned long long) size, (unsigned long long) max_addr);
803 
804 	return alloc;
805 }
806 
807 phys_addr_t __init memblock_alloc(phys_addr_t size, phys_addr_t align)
808 {
809 	return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
810 }
811 
812 phys_addr_t __init memblock_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
813 {
814 	phys_addr_t res = memblock_alloc_nid(size, align, nid);
815 
816 	if (res)
817 		return res;
818 	return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
819 }
820 
821 
822 /*
823  * Remaining API functions
824  */
825 
826 phys_addr_t __init memblock_phys_mem_size(void)
827 {
828 	return memblock.memory.total_size;
829 }
830 
831 /* lowest address */
832 phys_addr_t __init_memblock memblock_start_of_DRAM(void)
833 {
834 	return memblock.memory.regions[0].base;
835 }
836 
837 phys_addr_t __init_memblock memblock_end_of_DRAM(void)
838 {
839 	int idx = memblock.memory.cnt - 1;
840 
841 	return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
842 }
843 
844 void __init memblock_enforce_memory_limit(phys_addr_t limit)
845 {
846 	unsigned long i;
847 	phys_addr_t max_addr = (phys_addr_t)ULLONG_MAX;
848 
849 	if (!limit)
850 		return;
851 
852 	/* find out max address */
853 	for (i = 0; i < memblock.memory.cnt; i++) {
854 		struct memblock_region *r = &memblock.memory.regions[i];
855 
856 		if (limit <= r->size) {
857 			max_addr = r->base + limit;
858 			break;
859 		}
860 		limit -= r->size;
861 	}
862 
863 	/* truncate both memory and reserved regions */
864 	__memblock_remove(&memblock.memory, max_addr, (phys_addr_t)ULLONG_MAX);
865 	__memblock_remove(&memblock.reserved, max_addr, (phys_addr_t)ULLONG_MAX);
866 }
867 
868 static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
869 {
870 	unsigned int left = 0, right = type->cnt;
871 
872 	do {
873 		unsigned int mid = (right + left) / 2;
874 
875 		if (addr < type->regions[mid].base)
876 			right = mid;
877 		else if (addr >= (type->regions[mid].base +
878 				  type->regions[mid].size))
879 			left = mid + 1;
880 		else
881 			return mid;
882 	} while (left < right);
883 	return -1;
884 }
885 
886 int __init memblock_is_reserved(phys_addr_t addr)
887 {
888 	return memblock_search(&memblock.reserved, addr) != -1;
889 }
890 
891 int __init_memblock memblock_is_memory(phys_addr_t addr)
892 {
893 	return memblock_search(&memblock.memory, addr) != -1;
894 }
895 
896 /**
897  * memblock_is_region_memory - check if a region is a subset of memory
898  * @base: base of region to check
899  * @size: size of region to check
900  *
901  * Check if the region [@base, @base+@size) is a subset of a memory block.
902  *
903  * RETURNS:
904  * 0 if false, non-zero if true
905  */
906 int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
907 {
908 	int idx = memblock_search(&memblock.memory, base);
909 	phys_addr_t end = base + memblock_cap_size(base, &size);
910 
911 	if (idx == -1)
912 		return 0;
913 	return memblock.memory.regions[idx].base <= base &&
914 		(memblock.memory.regions[idx].base +
915 		 memblock.memory.regions[idx].size) >= end;
916 }
917 
918 /**
919  * memblock_is_region_reserved - check if a region intersects reserved memory
920  * @base: base of region to check
921  * @size: size of region to check
922  *
923  * Check if the region [@base, @base+@size) intersects a reserved memory block.
924  *
925  * RETURNS:
926  * 0 if false, non-zero if true
927  */
928 int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
929 {
930 	memblock_cap_size(base, &size);
931 	return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;
932 }
933 
934 void __init_memblock memblock_trim_memory(phys_addr_t align)
935 {
936 	int i;
937 	phys_addr_t start, end, orig_start, orig_end;
938 	struct memblock_type *mem = &memblock.memory;
939 
940 	for (i = 0; i < mem->cnt; i++) {
941 		orig_start = mem->regions[i].base;
942 		orig_end = mem->regions[i].base + mem->regions[i].size;
943 		start = round_up(orig_start, align);
944 		end = round_down(orig_end, align);
945 
946 		if (start == orig_start && end == orig_end)
947 			continue;
948 
949 		if (start < end) {
950 			mem->regions[i].base = start;
951 			mem->regions[i].size = end - start;
952 		} else {
953 			memblock_remove_region(mem, i);
954 			i--;
955 		}
956 	}
957 }
958 
959 void __init_memblock memblock_set_current_limit(phys_addr_t limit)
960 {
961 	memblock.current_limit = limit;
962 }
963 
964 static void __init_memblock memblock_dump(struct memblock_type *type, char *name)
965 {
966 	unsigned long long base, size;
967 	int i;
968 
969 	pr_info(" %s.cnt  = 0x%lx\n", name, type->cnt);
970 
971 	for (i = 0; i < type->cnt; i++) {
972 		struct memblock_region *rgn = &type->regions[i];
973 		char nid_buf[32] = "";
974 
975 		base = rgn->base;
976 		size = rgn->size;
977 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
978 		if (memblock_get_region_node(rgn) != MAX_NUMNODES)
979 			snprintf(nid_buf, sizeof(nid_buf), " on node %d",
980 				 memblock_get_region_node(rgn));
981 #endif
982 		pr_info(" %s[%#x]\t[%#016llx-%#016llx], %#llx bytes%s\n",
983 			name, i, base, base + size - 1, size, nid_buf);
984 	}
985 }
986 
987 void __init_memblock __memblock_dump_all(void)
988 {
989 	pr_info("MEMBLOCK configuration:\n");
990 	pr_info(" memory size = %#llx reserved size = %#llx\n",
991 		(unsigned long long)memblock.memory.total_size,
992 		(unsigned long long)memblock.reserved.total_size);
993 
994 	memblock_dump(&memblock.memory, "memory");
995 	memblock_dump(&memblock.reserved, "reserved");
996 }
997 
998 void __init memblock_allow_resize(void)
999 {
1000 	memblock_can_resize = 1;
1001 }
1002 
1003 static int __init early_memblock(char *p)
1004 {
1005 	if (p && strstr(p, "debug"))
1006 		memblock_debug = 1;
1007 	return 0;
1008 }
1009 early_param("memblock", early_memblock);
1010 
1011 #if defined(CONFIG_DEBUG_FS) && !defined(CONFIG_ARCH_DISCARD_MEMBLOCK)
1012 
1013 static int memblock_debug_show(struct seq_file *m, void *private)
1014 {
1015 	struct memblock_type *type = m->private;
1016 	struct memblock_region *reg;
1017 	int i;
1018 
1019 	for (i = 0; i < type->cnt; i++) {
1020 		reg = &type->regions[i];
1021 		seq_printf(m, "%4d: ", i);
1022 		if (sizeof(phys_addr_t) == 4)
1023 			seq_printf(m, "0x%08lx..0x%08lx\n",
1024 				   (unsigned long)reg->base,
1025 				   (unsigned long)(reg->base + reg->size - 1));
1026 		else
1027 			seq_printf(m, "0x%016llx..0x%016llx\n",
1028 				   (unsigned long long)reg->base,
1029 				   (unsigned long long)(reg->base + reg->size - 1));
1030 
1031 	}
1032 	return 0;
1033 }
1034 
1035 static int memblock_debug_open(struct inode *inode, struct file *file)
1036 {
1037 	return single_open(file, memblock_debug_show, inode->i_private);
1038 }
1039 
1040 static const struct file_operations memblock_debug_fops = {
1041 	.open = memblock_debug_open,
1042 	.read = seq_read,
1043 	.llseek = seq_lseek,
1044 	.release = single_release,
1045 };
1046 
1047 static int __init memblock_init_debugfs(void)
1048 {
1049 	struct dentry *root = debugfs_create_dir("memblock", NULL);
1050 	if (!root)
1051 		return -ENXIO;
1052 	debugfs_create_file("memory", S_IRUGO, root, &memblock.memory, &memblock_debug_fops);
1053 	debugfs_create_file("reserved", S_IRUGO, root, &memblock.reserved, &memblock_debug_fops);
1054 
1055 	return 0;
1056 }
1057 __initcall(memblock_init_debugfs);
1058 
1059 #endif /* CONFIG_DEBUG_FS */
1060