memblock: Reimplement memblock_enforce_memory_limit() using __memblock_remove()
[linux-2.6.git] / mm / memblock.c
blobb44875f5a9964aef9a5730a0386582a550155339
1 /*
2 * Procedures for maintaining information about logical memory blocks.
4 * Peter Bergner, IBM Corp. June 2001.
5 * Copyright (C) 2001 Peter Bergner.
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.
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>
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;
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,
31 .reserved.regions = memblock_reserved_init_regions,
32 .reserved.cnt = 1, /* empty dummy entry */
33 .reserved.max = INIT_MEMBLOCK_REGIONS,
35 .current_limit = MEMBLOCK_ALLOC_ANYWHERE,
38 int memblock_debug __initdata_memblock;
39 int memblock_can_resize __initdata_memblock;
41 /* inline so we don't get a warning when pr_debug is compiled out */
42 static inline const char *memblock_type_name(struct memblock_type *type)
44 if (type == &memblock.memory)
45 return "memory";
46 else if (type == &memblock.reserved)
47 return "reserved";
48 else
49 return "unknown";
52 /* adjust *@size so that (@base + *@size) doesn't overflow, return new size */
53 static inline phys_addr_t memblock_cap_size(phys_addr_t base, phys_addr_t *size)
55 return *size = min(*size, (phys_addr_t)ULLONG_MAX - base);
59 * Address comparison utilities
61 static unsigned long __init_memblock memblock_addrs_overlap(phys_addr_t base1, phys_addr_t size1,
62 phys_addr_t base2, phys_addr_t size2)
64 return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
67 static long __init_memblock memblock_overlaps_region(struct memblock_type *type,
68 phys_addr_t base, phys_addr_t size)
70 unsigned long i;
72 for (i = 0; i < type->cnt; i++) {
73 phys_addr_t rgnbase = type->regions[i].base;
74 phys_addr_t rgnsize = type->regions[i].size;
75 if (memblock_addrs_overlap(base, size, rgnbase, rgnsize))
76 break;
79 return (i < type->cnt) ? i : -1;
83 * Find, allocate, deallocate or reserve unreserved regions. All allocations
84 * are top-down.
87 static phys_addr_t __init_memblock memblock_find_region(phys_addr_t start, phys_addr_t end,
88 phys_addr_t size, phys_addr_t align)
90 phys_addr_t base, res_base;
91 long j;
93 /* In case, huge size is requested */
94 if (end < size)
95 return 0;
97 base = round_down(end - size, align);
99 /* Prevent allocations returning 0 as it's also used to
100 * indicate an allocation failure
102 if (start == 0)
103 start = PAGE_SIZE;
105 while (start <= base) {
106 j = memblock_overlaps_region(&memblock.reserved, base, size);
107 if (j < 0)
108 return base;
109 res_base = memblock.reserved.regions[j].base;
110 if (res_base < size)
111 break;
112 base = round_down(res_base - size, align);
115 return 0;
119 * Find a free area with specified alignment in a specific range.
121 phys_addr_t __init_memblock memblock_find_in_range(phys_addr_t start, phys_addr_t end,
122 phys_addr_t size, phys_addr_t align)
124 long i;
126 BUG_ON(0 == size);
128 /* Pump up max_addr */
129 if (end == MEMBLOCK_ALLOC_ACCESSIBLE)
130 end = memblock.current_limit;
132 /* We do a top-down search, this tends to limit memory
133 * fragmentation by keeping early boot allocs near the
134 * top of memory
136 for (i = memblock.memory.cnt - 1; i >= 0; i--) {
137 phys_addr_t memblockbase = memblock.memory.regions[i].base;
138 phys_addr_t memblocksize = memblock.memory.regions[i].size;
139 phys_addr_t bottom, top, found;
141 if (memblocksize < size)
142 continue;
143 if ((memblockbase + memblocksize) <= start)
144 break;
145 bottom = max(memblockbase, start);
146 top = min(memblockbase + memblocksize, end);
147 if (bottom >= top)
148 continue;
149 found = memblock_find_region(bottom, top, size, align);
150 if (found)
151 return found;
153 return 0;
157 * Free memblock.reserved.regions
159 int __init_memblock memblock_free_reserved_regions(void)
161 if (memblock.reserved.regions == memblock_reserved_init_regions)
162 return 0;
164 return memblock_free(__pa(memblock.reserved.regions),
165 sizeof(struct memblock_region) * memblock.reserved.max);
169 * Reserve memblock.reserved.regions
171 int __init_memblock memblock_reserve_reserved_regions(void)
173 if (memblock.reserved.regions == memblock_reserved_init_regions)
174 return 0;
176 return memblock_reserve(__pa(memblock.reserved.regions),
177 sizeof(struct memblock_region) * memblock.reserved.max);
180 static void __init_memblock memblock_remove_region(struct memblock_type *type, unsigned long r)
182 memmove(&type->regions[r], &type->regions[r + 1],
183 (type->cnt - (r + 1)) * sizeof(type->regions[r]));
184 type->cnt--;
186 /* Special case for empty arrays */
187 if (type->cnt == 0) {
188 type->cnt = 1;
189 type->regions[0].base = 0;
190 type->regions[0].size = 0;
191 memblock_set_region_node(&type->regions[0], MAX_NUMNODES);
195 static int __init_memblock memblock_double_array(struct memblock_type *type)
197 struct memblock_region *new_array, *old_array;
198 phys_addr_t old_size, new_size, addr;
199 int use_slab = slab_is_available();
201 /* We don't allow resizing until we know about the reserved regions
202 * of memory that aren't suitable for allocation
204 if (!memblock_can_resize)
205 return -1;
207 /* Calculate new doubled size */
208 old_size = type->max * sizeof(struct memblock_region);
209 new_size = old_size << 1;
211 /* Try to find some space for it.
213 * WARNING: We assume that either slab_is_available() and we use it or
214 * we use MEMBLOCK for allocations. That means that this is unsafe to use
215 * when bootmem is currently active (unless bootmem itself is implemented
216 * on top of MEMBLOCK which isn't the case yet)
218 * This should however not be an issue for now, as we currently only
219 * call into MEMBLOCK while it's still active, or much later when slab is
220 * active for memory hotplug operations
222 if (use_slab) {
223 new_array = kmalloc(new_size, GFP_KERNEL);
224 addr = new_array ? __pa(new_array) : 0;
225 } else
226 addr = memblock_find_in_range(0, MEMBLOCK_ALLOC_ACCESSIBLE, new_size, sizeof(phys_addr_t));
227 if (!addr) {
228 pr_err("memblock: Failed to double %s array from %ld to %ld entries !\n",
229 memblock_type_name(type), type->max, type->max * 2);
230 return -1;
232 new_array = __va(addr);
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);
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.
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;
247 /* If we use SLAB that's it, we are done */
248 if (use_slab)
249 return 0;
251 /* Add the new reserved region now. Should not fail ! */
252 BUG_ON(memblock_reserve(addr, new_size));
254 /* If the array wasn't our static init one, then free it. We only do
255 * that before SLAB is available as later on, we don't know whether
256 * to use kfree or free_bootmem_pages(). Shouldn't be a big deal
257 * anyways
259 if (old_array != memblock_memory_init_regions &&
260 old_array != memblock_reserved_init_regions)
261 memblock_free(__pa(old_array), old_size);
263 return 0;
267 * memblock_merge_regions - merge neighboring compatible regions
268 * @type: memblock type to scan
270 * Scan @type and merge neighboring compatible regions.
272 static void __init_memblock memblock_merge_regions(struct memblock_type *type)
274 int i = 0;
276 /* cnt never goes below 1 */
277 while (i < type->cnt - 1) {
278 struct memblock_region *this = &type->regions[i];
279 struct memblock_region *next = &type->regions[i + 1];
281 if (this->base + this->size != next->base ||
282 memblock_get_region_node(this) !=
283 memblock_get_region_node(next)) {
284 BUG_ON(this->base + this->size > next->base);
285 i++;
286 continue;
289 this->size += next->size;
290 memmove(next, next + 1, (type->cnt - (i + 1)) * sizeof(*next));
291 type->cnt--;
296 * memblock_insert_region - insert new memblock region
297 * @type: memblock type to insert into
298 * @idx: index for the insertion point
299 * @base: base address of the new region
300 * @size: size of the new region
302 * Insert new memblock region [@base,@base+@size) into @type at @idx.
303 * @type must already have extra room to accomodate the new region.
305 static void __init_memblock memblock_insert_region(struct memblock_type *type,
306 int idx, phys_addr_t base,
307 phys_addr_t size, int nid)
309 struct memblock_region *rgn = &type->regions[idx];
311 BUG_ON(type->cnt >= type->max);
312 memmove(rgn + 1, rgn, (type->cnt - idx) * sizeof(*rgn));
313 rgn->base = base;
314 rgn->size = size;
315 memblock_set_region_node(rgn, nid);
316 type->cnt++;
320 * memblock_add_region - add new memblock region
321 * @type: memblock type to add new region into
322 * @base: base address of the new region
323 * @size: size of the new region
325 * Add new memblock region [@base,@base+@size) into @type. The new region
326 * is allowed to overlap with existing ones - overlaps don't affect already
327 * existing regions. @type is guaranteed to be minimal (all neighbouring
328 * compatible regions are merged) after the addition.
330 * RETURNS:
331 * 0 on success, -errno on failure.
333 static int __init_memblock memblock_add_region(struct memblock_type *type,
334 phys_addr_t base, phys_addr_t size)
336 bool insert = false;
337 phys_addr_t obase = base;
338 phys_addr_t end = base + memblock_cap_size(base, &size);
339 int i, nr_new;
341 /* special case for empty array */
342 if (type->regions[0].size == 0) {
343 WARN_ON(type->cnt != 1);
344 type->regions[0].base = base;
345 type->regions[0].size = size;
346 memblock_set_region_node(&type->regions[0], MAX_NUMNODES);
347 return 0;
349 repeat:
351 * The following is executed twice. Once with %false @insert and
352 * then with %true. The first counts the number of regions needed
353 * to accomodate the new area. The second actually inserts them.
355 base = obase;
356 nr_new = 0;
358 for (i = 0; i < type->cnt; i++) {
359 struct memblock_region *rgn = &type->regions[i];
360 phys_addr_t rbase = rgn->base;
361 phys_addr_t rend = rbase + rgn->size;
363 if (rbase >= end)
364 break;
365 if (rend <= base)
366 continue;
368 * @rgn overlaps. If it separates the lower part of new
369 * area, insert that portion.
371 if (rbase > base) {
372 nr_new++;
373 if (insert)
374 memblock_insert_region(type, i++, base,
375 rbase - base, MAX_NUMNODES);
377 /* area below @rend is dealt with, forget about it */
378 base = min(rend, end);
381 /* insert the remaining portion */
382 if (base < end) {
383 nr_new++;
384 if (insert)
385 memblock_insert_region(type, i, base, end - base,
386 MAX_NUMNODES);
390 * If this was the first round, resize array and repeat for actual
391 * insertions; otherwise, merge and return.
393 if (!insert) {
394 while (type->cnt + nr_new > type->max)
395 if (memblock_double_array(type) < 0)
396 return -ENOMEM;
397 insert = true;
398 goto repeat;
399 } else {
400 memblock_merge_regions(type);
401 return 0;
405 int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
407 return memblock_add_region(&memblock.memory, base, size);
411 * memblock_isolate_range - isolate given range into disjoint memblocks
412 * @type: memblock type to isolate range for
413 * @base: base of range to isolate
414 * @size: size of range to isolate
415 * @start_rgn: out parameter for the start of isolated region
416 * @end_rgn: out parameter for the end of isolated region
418 * Walk @type and ensure that regions don't cross the boundaries defined by
419 * [@base,@base+@size). Crossing regions are split at the boundaries,
420 * which may create at most two more regions. The index of the first
421 * region inside the range is returned in *@start_rgn and end in *@end_rgn.
423 * RETURNS:
424 * 0 on success, -errno on failure.
426 static int __init_memblock memblock_isolate_range(struct memblock_type *type,
427 phys_addr_t base, phys_addr_t size,
428 int *start_rgn, int *end_rgn)
430 phys_addr_t end = base + memblock_cap_size(base, &size);
431 int i;
433 *start_rgn = *end_rgn = 0;
435 /* we'll create at most two more regions */
436 while (type->cnt + 2 > type->max)
437 if (memblock_double_array(type) < 0)
438 return -ENOMEM;
440 for (i = 0; i < type->cnt; i++) {
441 struct memblock_region *rgn = &type->regions[i];
442 phys_addr_t rbase = rgn->base;
443 phys_addr_t rend = rbase + rgn->size;
445 if (rbase >= end)
446 break;
447 if (rend <= base)
448 continue;
450 if (rbase < base) {
452 * @rgn intersects from below. Split and continue
453 * to process the next region - the new top half.
455 rgn->base = base;
456 rgn->size = rend - rgn->base;
457 memblock_insert_region(type, i, rbase, base - rbase,
458 memblock_get_region_node(rgn));
459 } else if (rend > end) {
461 * @rgn intersects from above. Split and redo the
462 * current region - the new bottom half.
464 rgn->base = end;
465 rgn->size = rend - rgn->base;
466 memblock_insert_region(type, i--, rbase, end - rbase,
467 memblock_get_region_node(rgn));
468 } else {
469 /* @rgn is fully contained, record it */
470 if (!*end_rgn)
471 *start_rgn = i;
472 *end_rgn = i + 1;
476 return 0;
479 static int __init_memblock __memblock_remove(struct memblock_type *type,
480 phys_addr_t base, phys_addr_t size)
482 int start_rgn, end_rgn;
483 int i, ret;
485 ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
486 if (ret)
487 return ret;
489 for (i = end_rgn - 1; i >= start_rgn; i--)
490 memblock_remove_region(type, i);
491 return 0;
494 int __init_memblock memblock_remove(phys_addr_t base, phys_addr_t size)
496 return __memblock_remove(&memblock.memory, base, size);
499 int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)
501 memblock_dbg(" memblock_free: [%#016llx-%#016llx] %pF\n",
502 (unsigned long long)base,
503 (unsigned long long)base + size,
504 (void *)_RET_IP_);
506 return __memblock_remove(&memblock.reserved, base, size);
509 int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
511 struct memblock_type *_rgn = &memblock.reserved;
513 memblock_dbg("memblock_reserve: [%#016llx-%#016llx] %pF\n",
514 (unsigned long long)base,
515 (unsigned long long)base + size,
516 (void *)_RET_IP_);
517 BUG_ON(0 == size);
519 return memblock_add_region(_rgn, base, size);
523 * __next_free_mem_range - next function for for_each_free_mem_range()
524 * @idx: pointer to u64 loop variable
525 * @nid: nid: node selector, %MAX_NUMNODES for all nodes
526 * @p_start: ptr to phys_addr_t for start address of the range, can be %NULL
527 * @p_end: ptr to phys_addr_t for end address of the range, can be %NULL
528 * @p_nid: ptr to int for nid of the range, can be %NULL
530 * Find the first free area from *@idx which matches @nid, fill the out
531 * parameters, and update *@idx for the next iteration. The lower 32bit of
532 * *@idx contains index into memory region and the upper 32bit indexes the
533 * areas before each reserved region. For example, if reserved regions
534 * look like the following,
536 * 0:[0-16), 1:[32-48), 2:[128-130)
538 * The upper 32bit indexes the following regions.
540 * 0:[0-0), 1:[16-32), 2:[48-128), 3:[130-MAX)
542 * As both region arrays are sorted, the function advances the two indices
543 * in lockstep and returns each intersection.
545 void __init_memblock __next_free_mem_range(u64 *idx, int nid,
546 phys_addr_t *out_start,
547 phys_addr_t *out_end, int *out_nid)
549 struct memblock_type *mem = &memblock.memory;
550 struct memblock_type *rsv = &memblock.reserved;
551 int mi = *idx & 0xffffffff;
552 int ri = *idx >> 32;
554 for ( ; mi < mem->cnt; mi++) {
555 struct memblock_region *m = &mem->regions[mi];
556 phys_addr_t m_start = m->base;
557 phys_addr_t m_end = m->base + m->size;
559 /* only memory regions are associated with nodes, check it */
560 if (nid != MAX_NUMNODES && nid != memblock_get_region_node(m))
561 continue;
563 /* scan areas before each reservation for intersection */
564 for ( ; ri < rsv->cnt + 1; ri++) {
565 struct memblock_region *r = &rsv->regions[ri];
566 phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
567 phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
569 /* if ri advanced past mi, break out to advance mi */
570 if (r_start >= m_end)
571 break;
572 /* if the two regions intersect, we're done */
573 if (m_start < r_end) {
574 if (out_start)
575 *out_start = max(m_start, r_start);
576 if (out_end)
577 *out_end = min(m_end, r_end);
578 if (out_nid)
579 *out_nid = memblock_get_region_node(m);
581 * The region which ends first is advanced
582 * for the next iteration.
584 if (m_end <= r_end)
585 mi++;
586 else
587 ri++;
588 *idx = (u32)mi | (u64)ri << 32;
589 return;
594 /* signal end of iteration */
595 *idx = ULLONG_MAX;
598 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
600 * Common iterator interface used to define for_each_mem_range().
602 void __init_memblock __next_mem_pfn_range(int *idx, int nid,
603 unsigned long *out_start_pfn,
604 unsigned long *out_end_pfn, int *out_nid)
606 struct memblock_type *type = &memblock.memory;
607 struct memblock_region *r;
609 while (++*idx < type->cnt) {
610 r = &type->regions[*idx];
612 if (PFN_UP(r->base) >= PFN_DOWN(r->base + r->size))
613 continue;
614 if (nid == MAX_NUMNODES || nid == r->nid)
615 break;
617 if (*idx >= type->cnt) {
618 *idx = -1;
619 return;
622 if (out_start_pfn)
623 *out_start_pfn = PFN_UP(r->base);
624 if (out_end_pfn)
625 *out_end_pfn = PFN_DOWN(r->base + r->size);
626 if (out_nid)
627 *out_nid = r->nid;
631 * memblock_set_node - set node ID on memblock regions
632 * @base: base of area to set node ID for
633 * @size: size of area to set node ID for
634 * @nid: node ID to set
636 * Set the nid of memblock memory regions in [@base,@base+@size) to @nid.
637 * Regions which cross the area boundaries are split as necessary.
639 * RETURNS:
640 * 0 on success, -errno on failure.
642 int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
643 int nid)
645 struct memblock_type *type = &memblock.memory;
646 int start_rgn, end_rgn;
647 int i, ret;
649 ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
650 if (ret)
651 return ret;
653 for (i = start_rgn; i < end_rgn; i++)
654 type->regions[i].nid = nid;
656 memblock_merge_regions(type);
657 return 0;
659 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
661 phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
663 phys_addr_t found;
665 /* We align the size to limit fragmentation. Without this, a lot of
666 * small allocs quickly eat up the whole reserve array on sparc
668 size = round_up(size, align);
670 found = memblock_find_in_range(0, max_addr, size, align);
671 if (found && !memblock_reserve(found, size))
672 return found;
674 return 0;
677 phys_addr_t __init memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
679 phys_addr_t alloc;
681 alloc = __memblock_alloc_base(size, align, max_addr);
683 if (alloc == 0)
684 panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
685 (unsigned long long) size, (unsigned long long) max_addr);
687 return alloc;
690 phys_addr_t __init memblock_alloc(phys_addr_t size, phys_addr_t align)
692 return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
697 * Additional node-local top-down allocators.
699 * WARNING: Only available after early_node_map[] has been populated,
700 * on some architectures, that is after all the calls to add_active_range()
701 * have been done to populate it.
704 static phys_addr_t __init memblock_nid_range_rev(phys_addr_t start,
705 phys_addr_t end, int *nid)
707 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
708 unsigned long start_pfn, end_pfn;
709 int i;
711 for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, nid)
712 if (end > PFN_PHYS(start_pfn) && end <= PFN_PHYS(end_pfn))
713 return max(start, PFN_PHYS(start_pfn));
714 #endif
715 *nid = 0;
716 return start;
719 phys_addr_t __init memblock_find_in_range_node(phys_addr_t start,
720 phys_addr_t end,
721 phys_addr_t size,
722 phys_addr_t align, int nid)
724 struct memblock_type *mem = &memblock.memory;
725 int i;
727 BUG_ON(0 == size);
729 /* Pump up max_addr */
730 if (end == MEMBLOCK_ALLOC_ACCESSIBLE)
731 end = memblock.current_limit;
733 for (i = mem->cnt - 1; i >= 0; i--) {
734 struct memblock_region *r = &mem->regions[i];
735 phys_addr_t base = max(start, r->base);
736 phys_addr_t top = min(end, r->base + r->size);
738 while (base < top) {
739 phys_addr_t tbase, ret;
740 int tnid;
742 tbase = memblock_nid_range_rev(base, top, &tnid);
743 if (nid == MAX_NUMNODES || tnid == nid) {
744 ret = memblock_find_region(tbase, top, size, align);
745 if (ret)
746 return ret;
748 top = tbase;
752 return 0;
755 phys_addr_t __init memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int nid)
757 phys_addr_t found;
760 * We align the size to limit fragmentation. Without this, a lot of
761 * small allocs quickly eat up the whole reserve array on sparc
763 size = round_up(size, align);
765 found = memblock_find_in_range_node(0, MEMBLOCK_ALLOC_ACCESSIBLE,
766 size, align, nid);
767 if (found && !memblock_reserve(found, size))
768 return found;
770 return 0;
773 phys_addr_t __init memblock_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
775 phys_addr_t res = memblock_alloc_nid(size, align, nid);
777 if (res)
778 return res;
779 return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
784 * Remaining API functions
787 /* You must call memblock_analyze() before this. */
788 phys_addr_t __init memblock_phys_mem_size(void)
790 return memblock.memory_size;
793 /* lowest address */
794 phys_addr_t __init_memblock memblock_start_of_DRAM(void)
796 return memblock.memory.regions[0].base;
799 phys_addr_t __init_memblock memblock_end_of_DRAM(void)
801 int idx = memblock.memory.cnt - 1;
803 return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
806 /* You must call memblock_analyze() after this. */
807 void __init memblock_enforce_memory_limit(phys_addr_t limit)
809 unsigned long i;
810 phys_addr_t max_addr = (phys_addr_t)ULLONG_MAX;
812 if (!limit)
813 return;
815 /* find out max address */
816 for (i = 0; i < memblock.memory.cnt; i++) {
817 struct memblock_region *r = &memblock.memory.regions[i];
819 if (limit <= r->size) {
820 max_addr = r->base + limit;
821 break;
823 limit -= r->size;
826 /* truncate both memory and reserved regions */
827 __memblock_remove(&memblock.memory, max_addr, (phys_addr_t)ULLONG_MAX);
828 __memblock_remove(&memblock.reserved, max_addr, (phys_addr_t)ULLONG_MAX);
831 static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
833 unsigned int left = 0, right = type->cnt;
835 do {
836 unsigned int mid = (right + left) / 2;
838 if (addr < type->regions[mid].base)
839 right = mid;
840 else if (addr >= (type->regions[mid].base +
841 type->regions[mid].size))
842 left = mid + 1;
843 else
844 return mid;
845 } while (left < right);
846 return -1;
849 int __init memblock_is_reserved(phys_addr_t addr)
851 return memblock_search(&memblock.reserved, addr) != -1;
854 int __init_memblock memblock_is_memory(phys_addr_t addr)
856 return memblock_search(&memblock.memory, addr) != -1;
859 int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
861 int idx = memblock_search(&memblock.memory, base);
862 phys_addr_t end = base + memblock_cap_size(base, &size);
864 if (idx == -1)
865 return 0;
866 return memblock.memory.regions[idx].base <= base &&
867 (memblock.memory.regions[idx].base +
868 memblock.memory.regions[idx].size) >= end;
871 int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
873 memblock_cap_size(base, &size);
874 return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;
878 void __init_memblock memblock_set_current_limit(phys_addr_t limit)
880 memblock.current_limit = limit;
883 static void __init_memblock memblock_dump(struct memblock_type *type, char *name)
885 unsigned long long base, size;
886 int i;
888 pr_info(" %s.cnt = 0x%lx\n", name, type->cnt);
890 for (i = 0; i < type->cnt; i++) {
891 struct memblock_region *rgn = &type->regions[i];
892 char nid_buf[32] = "";
894 base = rgn->base;
895 size = rgn->size;
896 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
897 if (memblock_get_region_node(rgn) != MAX_NUMNODES)
898 snprintf(nid_buf, sizeof(nid_buf), " on node %d",
899 memblock_get_region_node(rgn));
900 #endif
901 pr_info(" %s[%#x]\t[%#016llx-%#016llx], %#llx bytes%s\n",
902 name, i, base, base + size - 1, size, nid_buf);
906 void __init_memblock __memblock_dump_all(void)
908 pr_info("MEMBLOCK configuration:\n");
909 pr_info(" memory size = 0x%llx\n", (unsigned long long)memblock.memory_size);
911 memblock_dump(&memblock.memory, "memory");
912 memblock_dump(&memblock.reserved, "reserved");
915 void __init memblock_analyze(void)
917 int i;
919 memblock.memory_size = 0;
921 for (i = 0; i < memblock.memory.cnt; i++)
922 memblock.memory_size += memblock.memory.regions[i].size;
924 /* We allow resizing from there */
925 memblock_can_resize = 1;
928 static int __init early_memblock(char *p)
930 if (p && strstr(p, "debug"))
931 memblock_debug = 1;
932 return 0;
934 early_param("memblock", early_memblock);
936 #if defined(CONFIG_DEBUG_FS) && !defined(CONFIG_ARCH_DISCARD_MEMBLOCK)
938 static int memblock_debug_show(struct seq_file *m, void *private)
940 struct memblock_type *type = m->private;
941 struct memblock_region *reg;
942 int i;
944 for (i = 0; i < type->cnt; i++) {
945 reg = &type->regions[i];
946 seq_printf(m, "%4d: ", i);
947 if (sizeof(phys_addr_t) == 4)
948 seq_printf(m, "0x%08lx..0x%08lx\n",
949 (unsigned long)reg->base,
950 (unsigned long)(reg->base + reg->size - 1));
951 else
952 seq_printf(m, "0x%016llx..0x%016llx\n",
953 (unsigned long long)reg->base,
954 (unsigned long long)(reg->base + reg->size - 1));
957 return 0;
960 static int memblock_debug_open(struct inode *inode, struct file *file)
962 return single_open(file, memblock_debug_show, inode->i_private);
965 static const struct file_operations memblock_debug_fops = {
966 .open = memblock_debug_open,
967 .read = seq_read,
968 .llseek = seq_lseek,
969 .release = single_release,
972 static int __init memblock_init_debugfs(void)
974 struct dentry *root = debugfs_create_dir("memblock", NULL);
975 if (!root)
976 return -ENXIO;
977 debugfs_create_file("memory", S_IRUGO, root, &memblock.memory, &memblock_debug_fops);
978 debugfs_create_file("reserved", S_IRUGO, root, &memblock.reserved, &memblock_debug_fops);
980 return 0;
982 __initcall(memblock_init_debugfs);
984 #endif /* CONFIG_DEBUG_FS */