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 #include <asm-generic/sections.h>
28 static struct memblock_region memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS] __initdata_memblock;
29 static struct memblock_region memblock_reserved_init_regions[INIT_MEMBLOCK_REGIONS] __initdata_memblock;
31 struct memblock memblock __initdata_memblock = {
32 .memory.regions = memblock_memory_init_regions,
33 .memory.cnt = 1, /* empty dummy entry */
34 .memory.max = INIT_MEMBLOCK_REGIONS,
36 .reserved.regions = memblock_reserved_init_regions,
37 .reserved.cnt = 1, /* empty dummy entry */
38 .reserved.max = INIT_MEMBLOCK_REGIONS,
41 .current_limit = MEMBLOCK_ALLOC_ANYWHERE,
44 int memblock_debug __initdata_memblock;
45 #ifdef CONFIG_MOVABLE_NODE
46 bool movable_node_enabled __initdata_memblock = false;
48 static int memblock_can_resize __initdata_memblock;
49 static int memblock_memory_in_slab __initdata_memblock = 0;
50 static int memblock_reserved_in_slab __initdata_memblock = 0;
52 /* inline so we don't get a warning when pr_debug is compiled out */
53 static __init_memblock const char *
54 memblock_type_name(struct memblock_type *type)
56 if (type == &memblock.memory)
58 else if (type == &memblock.reserved)
64 /* adjust *@size so that (@base + *@size) doesn't overflow, return new size */
65 static inline phys_addr_t memblock_cap_size(phys_addr_t base, phys_addr_t *size)
67 return *size = min(*size, (phys_addr_t)ULLONG_MAX - base);
71 * Address comparison utilities
73 static unsigned long __init_memblock memblock_addrs_overlap(phys_addr_t base1, phys_addr_t size1,
74 phys_addr_t base2, phys_addr_t size2)
76 return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
79 static long __init_memblock memblock_overlaps_region(struct memblock_type *type,
80 phys_addr_t base, phys_addr_t size)
84 for (i = 0; i < type->cnt; i++) {
85 phys_addr_t rgnbase = type->regions[i].base;
86 phys_addr_t rgnsize = type->regions[i].size;
87 if (memblock_addrs_overlap(base, size, rgnbase, rgnsize))
91 return (i < type->cnt) ? i : -1;
95 * __memblock_find_range_bottom_up - find free area utility in bottom-up
96 * @start: start of candidate range
97 * @end: end of candidate range, can be %MEMBLOCK_ALLOC_{ANYWHERE|ACCESSIBLE}
98 * @size: size of free area to find
99 * @align: alignment of free area to find
100 * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
102 * Utility called from memblock_find_in_range_node(), find free area bottom-up.
105 * Found address on success, 0 on failure.
107 static phys_addr_t __init_memblock
108 __memblock_find_range_bottom_up(phys_addr_t start, phys_addr_t end,
109 phys_addr_t size, phys_addr_t align, int nid)
111 phys_addr_t this_start, this_end, cand;
114 for_each_free_mem_range(i, nid, &this_start, &this_end, NULL) {
115 this_start = clamp(this_start, start, end);
116 this_end = clamp(this_end, start, end);
118 cand = round_up(this_start, align);
119 if (cand < this_end && this_end - cand >= size)
127 * __memblock_find_range_top_down - find free area utility, in top-down
128 * @start: start of candidate range
129 * @end: end of candidate range, can be %MEMBLOCK_ALLOC_{ANYWHERE|ACCESSIBLE}
130 * @size: size of free area to find
131 * @align: alignment of free area to find
132 * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
134 * Utility called from memblock_find_in_range_node(), find free area top-down.
137 * Found address on success, 0 on failure.
139 static phys_addr_t __init_memblock
140 __memblock_find_range_top_down(phys_addr_t start, phys_addr_t end,
141 phys_addr_t size, phys_addr_t align, int nid)
143 phys_addr_t this_start, this_end, cand;
146 for_each_free_mem_range_reverse(i, nid, &this_start, &this_end, NULL) {
147 this_start = clamp(this_start, start, end);
148 this_end = clamp(this_end, start, end);
153 cand = round_down(this_end - size, align);
154 if (cand >= this_start)
162 * memblock_find_in_range_node - find free area in given range and node
163 * @size: size of free area to find
164 * @align: alignment of free area to find
165 * @start: start of candidate range
166 * @end: end of candidate range, can be %MEMBLOCK_ALLOC_{ANYWHERE|ACCESSIBLE}
167 * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
169 * Find @size free area aligned to @align in the specified range and node.
171 * When allocation direction is bottom-up, the @start should be greater
172 * than the end of the kernel image. Otherwise, it will be trimmed. The
173 * reason is that we want the bottom-up allocation just near the kernel
174 * image so it is highly likely that the allocated memory and the kernel
175 * will reside in the same node.
177 * If bottom-up allocation failed, will try to allocate memory top-down.
180 * Found address on success, 0 on failure.
182 phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t size,
183 phys_addr_t align, phys_addr_t start,
184 phys_addr_t end, int nid)
187 phys_addr_t kernel_end;
190 if (end == MEMBLOCK_ALLOC_ACCESSIBLE)
191 end = memblock.current_limit;
193 /* avoid allocating the first page */
194 start = max_t(phys_addr_t, start, PAGE_SIZE);
195 end = max(start, end);
196 kernel_end = __pa_symbol(_end);
199 * try bottom-up allocation only when bottom-up mode
200 * is set and @end is above the kernel image.
202 if (memblock_bottom_up() && end > kernel_end) {
203 phys_addr_t bottom_up_start;
205 /* make sure we will allocate above the kernel */
206 bottom_up_start = max(start, kernel_end);
208 /* ok, try bottom-up allocation first */
209 ret = __memblock_find_range_bottom_up(bottom_up_start, end,
215 * we always limit bottom-up allocation above the kernel,
216 * but top-down allocation doesn't have the limit, so
217 * retrying top-down allocation may succeed when bottom-up
220 * bottom-up allocation is expected to be fail very rarely,
221 * so we use WARN_ONCE() here to see the stack trace if
224 WARN_ONCE(1, "memblock: bottom-up allocation failed, "
225 "memory hotunplug may be affected\n");
228 return __memblock_find_range_top_down(start, end, size, align, nid);
232 * memblock_find_in_range - find free area in given range
233 * @start: start of candidate range
234 * @end: end of candidate range, can be %MEMBLOCK_ALLOC_{ANYWHERE|ACCESSIBLE}
235 * @size: size of free area to find
236 * @align: alignment of free area to find
238 * Find @size free area aligned to @align in the specified range.
241 * Found address on success, 0 on failure.
243 phys_addr_t __init_memblock memblock_find_in_range(phys_addr_t start,
244 phys_addr_t end, phys_addr_t size,
247 return memblock_find_in_range_node(size, align, start, end,
251 static void __init_memblock memblock_remove_region(struct memblock_type *type, unsigned long r)
253 type->total_size -= type->regions[r].size;
254 memmove(&type->regions[r], &type->regions[r + 1],
255 (type->cnt - (r + 1)) * sizeof(type->regions[r]));
258 /* Special case for empty arrays */
259 if (type->cnt == 0) {
260 WARN_ON(type->total_size != 0);
262 type->regions[0].base = 0;
263 type->regions[0].size = 0;
264 type->regions[0].flags = 0;
265 memblock_set_region_node(&type->regions[0], MAX_NUMNODES);
269 phys_addr_t __init_memblock get_allocated_memblock_reserved_regions_info(
272 if (memblock.reserved.regions == memblock_reserved_init_regions)
276 * Don't allow nobootmem allocator to free reserved memory regions
278 * - CONFIG_DEBUG_FS is enabled;
279 * - CONFIG_ARCH_DISCARD_MEMBLOCK is not enabled;
280 * - reserved memory regions array have been resized during boot.
281 * Otherwise debug_fs entry "sys/kernel/debug/memblock/reserved"
282 * will show garbage instead of state of memory reservations.
284 if (IS_ENABLED(CONFIG_DEBUG_FS) &&
285 !IS_ENABLED(CONFIG_ARCH_DISCARD_MEMBLOCK))
288 *addr = __pa(memblock.reserved.regions);
290 return PAGE_ALIGN(sizeof(struct memblock_region) *
291 memblock.reserved.max);
295 * memblock_double_array - double the size of the memblock regions array
296 * @type: memblock type of the regions array being doubled
297 * @new_area_start: starting address of memory range to avoid overlap with
298 * @new_area_size: size of memory range to avoid overlap with
300 * Double the size of the @type regions array. If memblock is being used to
301 * allocate memory for a new reserved regions array and there is a previously
302 * allocated memory range [@new_area_start,@new_area_start+@new_area_size]
303 * waiting to be reserved, ensure the memory used by the new array does
307 * 0 on success, -1 on failure.
309 static int __init_memblock memblock_double_array(struct memblock_type *type,
310 phys_addr_t new_area_start,
311 phys_addr_t new_area_size)
313 struct memblock_region *new_array, *old_array;
314 phys_addr_t old_alloc_size, new_alloc_size;
315 phys_addr_t old_size, new_size, addr;
316 int use_slab = slab_is_available();
319 /* We don't allow resizing until we know about the reserved regions
320 * of memory that aren't suitable for allocation
322 if (!memblock_can_resize)
325 /* Calculate new doubled size */
326 old_size = type->max * sizeof(struct memblock_region);
327 new_size = old_size << 1;
329 * We need to allocated new one align to PAGE_SIZE,
330 * so we can free them completely later.
332 old_alloc_size = PAGE_ALIGN(old_size);
333 new_alloc_size = PAGE_ALIGN(new_size);
335 /* Retrieve the slab flag */
336 if (type == &memblock.memory)
337 in_slab = &memblock_memory_in_slab;
339 in_slab = &memblock_reserved_in_slab;
341 /* Try to find some space for it.
343 * WARNING: We assume that either slab_is_available() and we use it or
344 * we use MEMBLOCK for allocations. That means that this is unsafe to
345 * use when bootmem is currently active (unless bootmem itself is
346 * implemented on top of MEMBLOCK which isn't the case yet)
348 * This should however not be an issue for now, as we currently only
349 * call into MEMBLOCK while it's still active, or much later when slab
350 * is active for memory hotplug operations
353 new_array = kmalloc(new_size, GFP_KERNEL);
354 addr = new_array ? __pa(new_array) : 0;
356 /* only exclude range when trying to double reserved.regions */
357 if (type != &memblock.reserved)
358 new_area_start = new_area_size = 0;
360 addr = memblock_find_in_range(new_area_start + new_area_size,
361 memblock.current_limit,
362 new_alloc_size, PAGE_SIZE);
363 if (!addr && new_area_size)
364 addr = memblock_find_in_range(0,
365 min(new_area_start, memblock.current_limit),
366 new_alloc_size, PAGE_SIZE);
368 new_array = addr ? __va(addr) : NULL;
371 pr_err("memblock: Failed to double %s array from %ld to %ld entries !\n",
372 memblock_type_name(type), type->max, type->max * 2);
376 memblock_dbg("memblock: %s is doubled to %ld at [%#010llx-%#010llx]",
377 memblock_type_name(type), type->max * 2, (u64)addr,
378 (u64)addr + new_size - 1);
381 * Found space, we now need to move the array over before we add the
382 * reserved region since it may be our reserved array itself that is
385 memcpy(new_array, type->regions, old_size);
386 memset(new_array + type->max, 0, old_size);
387 old_array = type->regions;
388 type->regions = new_array;
391 /* Free old array. We needn't free it if the array is the static one */
394 else if (old_array != memblock_memory_init_regions &&
395 old_array != memblock_reserved_init_regions)
396 memblock_free(__pa(old_array), old_alloc_size);
399 * Reserve the new array if that comes from the memblock. Otherwise, we
403 BUG_ON(memblock_reserve(addr, new_alloc_size));
405 /* Update slab flag */
412 * memblock_merge_regions - merge neighboring compatible regions
413 * @type: memblock type to scan
415 * Scan @type and merge neighboring compatible regions.
417 static void __init_memblock memblock_merge_regions(struct memblock_type *type)
421 /* cnt never goes below 1 */
422 while (i < type->cnt - 1) {
423 struct memblock_region *this = &type->regions[i];
424 struct memblock_region *next = &type->regions[i + 1];
426 if (this->base + this->size != next->base ||
427 memblock_get_region_node(this) !=
428 memblock_get_region_node(next) ||
429 this->flags != next->flags) {
430 BUG_ON(this->base + this->size > next->base);
435 this->size += next->size;
436 /* move forward from next + 1, index of which is i + 2 */
437 memmove(next, next + 1, (type->cnt - (i + 2)) * sizeof(*next));
443 * memblock_insert_region - insert new memblock region
444 * @type: memblock type to insert into
445 * @idx: index for the insertion point
446 * @base: base address of the new region
447 * @size: size of the new region
448 * @nid: node id of the new region
449 * @flags: flags of the new region
451 * Insert new memblock region [@base,@base+@size) into @type at @idx.
452 * @type must already have extra room to accomodate the new region.
454 static void __init_memblock memblock_insert_region(struct memblock_type *type,
455 int idx, phys_addr_t base,
457 int nid, unsigned long flags)
459 struct memblock_region *rgn = &type->regions[idx];
461 BUG_ON(type->cnt >= type->max);
462 memmove(rgn + 1, rgn, (type->cnt - idx) * sizeof(*rgn));
466 memblock_set_region_node(rgn, nid);
468 type->total_size += size;
472 * memblock_add_region - add new memblock region
473 * @type: memblock type to add new region into
474 * @base: base address of the new region
475 * @size: size of the new region
476 * @nid: nid of the new region
477 * @flags: flags of the new region
479 * Add new memblock region [@base,@base+@size) into @type. The new region
480 * is allowed to overlap with existing ones - overlaps don't affect already
481 * existing regions. @type is guaranteed to be minimal (all neighbouring
482 * compatible regions are merged) after the addition.
485 * 0 on success, -errno on failure.
487 static int __init_memblock memblock_add_region(struct memblock_type *type,
488 phys_addr_t base, phys_addr_t size,
489 int nid, unsigned long flags)
492 phys_addr_t obase = base;
493 phys_addr_t end = base + memblock_cap_size(base, &size);
499 /* special case for empty array */
500 if (type->regions[0].size == 0) {
501 WARN_ON(type->cnt != 1 || type->total_size);
502 type->regions[0].base = base;
503 type->regions[0].size = size;
504 type->regions[0].flags = flags;
505 memblock_set_region_node(&type->regions[0], nid);
506 type->total_size = size;
511 * The following is executed twice. Once with %false @insert and
512 * then with %true. The first counts the number of regions needed
513 * to accomodate the new area. The second actually inserts them.
518 for (i = 0; i < type->cnt; i++) {
519 struct memblock_region *rgn = &type->regions[i];
520 phys_addr_t rbase = rgn->base;
521 phys_addr_t rend = rbase + rgn->size;
528 * @rgn overlaps. If it separates the lower part of new
529 * area, insert that portion.
534 memblock_insert_region(type, i++, base,
538 /* area below @rend is dealt with, forget about it */
539 base = min(rend, end);
542 /* insert the remaining portion */
546 memblock_insert_region(type, i, base, end - base,
551 * If this was the first round, resize array and repeat for actual
552 * insertions; otherwise, merge and return.
555 while (type->cnt + nr_new > type->max)
556 if (memblock_double_array(type, obase, size) < 0)
561 memblock_merge_regions(type);
566 int __init_memblock memblock_add_node(phys_addr_t base, phys_addr_t size,
569 return memblock_add_region(&memblock.memory, base, size, nid, 0);
572 int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
574 return memblock_add_region(&memblock.memory, base, size,
579 * memblock_isolate_range - isolate given range into disjoint memblocks
580 * @type: memblock type to isolate range for
581 * @base: base of range to isolate
582 * @size: size of range to isolate
583 * @start_rgn: out parameter for the start of isolated region
584 * @end_rgn: out parameter for the end of isolated region
586 * Walk @type and ensure that regions don't cross the boundaries defined by
587 * [@base,@base+@size). Crossing regions are split at the boundaries,
588 * which may create at most two more regions. The index of the first
589 * region inside the range is returned in *@start_rgn and end in *@end_rgn.
592 * 0 on success, -errno on failure.
594 static int __init_memblock memblock_isolate_range(struct memblock_type *type,
595 phys_addr_t base, phys_addr_t size,
596 int *start_rgn, int *end_rgn)
598 phys_addr_t end = base + memblock_cap_size(base, &size);
601 *start_rgn = *end_rgn = 0;
606 /* we'll create at most two more regions */
607 while (type->cnt + 2 > type->max)
608 if (memblock_double_array(type, base, size) < 0)
611 for (i = 0; i < type->cnt; i++) {
612 struct memblock_region *rgn = &type->regions[i];
613 phys_addr_t rbase = rgn->base;
614 phys_addr_t rend = rbase + rgn->size;
623 * @rgn intersects from below. Split and continue
624 * to process the next region - the new top half.
627 rgn->size -= base - rbase;
628 type->total_size -= base - rbase;
629 memblock_insert_region(type, i, rbase, base - rbase,
630 memblock_get_region_node(rgn),
632 } else if (rend > end) {
634 * @rgn intersects from above. Split and redo the
635 * current region - the new bottom half.
638 rgn->size -= end - rbase;
639 type->total_size -= end - rbase;
640 memblock_insert_region(type, i--, rbase, end - rbase,
641 memblock_get_region_node(rgn),
644 /* @rgn is fully contained, record it */
654 static int __init_memblock __memblock_remove(struct memblock_type *type,
655 phys_addr_t base, phys_addr_t size)
657 int start_rgn, end_rgn;
660 ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
664 for (i = end_rgn - 1; i >= start_rgn; i--)
665 memblock_remove_region(type, i);
669 int __init_memblock memblock_remove(phys_addr_t base, phys_addr_t size)
671 return __memblock_remove(&memblock.memory, base, size);
674 int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)
676 memblock_dbg(" memblock_free: [%#016llx-%#016llx] %pF\n",
677 (unsigned long long)base,
678 (unsigned long long)base + size - 1,
681 return __memblock_remove(&memblock.reserved, base, size);
684 static int __init_memblock memblock_reserve_region(phys_addr_t base,
689 struct memblock_type *_rgn = &memblock.reserved;
691 memblock_dbg("memblock_reserve: [%#016llx-%#016llx] flags %#02lx %pF\n",
692 (unsigned long long)base,
693 (unsigned long long)base + size - 1,
694 flags, (void *)_RET_IP_);
696 return memblock_add_region(_rgn, base, size, nid, flags);
699 int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
701 return memblock_reserve_region(base, size, MAX_NUMNODES, 0);
705 * memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
706 * @base: the base phys addr of the region
707 * @size: the size of the region
709 * This function isolates region [@base, @base + @size), and mark it with flag
712 * Return 0 on succees, -errno on failure.
714 int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
716 struct memblock_type *type = &memblock.memory;
717 int i, ret, start_rgn, end_rgn;
719 ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
723 for (i = start_rgn; i < end_rgn; i++)
724 memblock_set_region_flags(&type->regions[i], MEMBLOCK_HOTPLUG);
726 memblock_merge_regions(type);
731 * memblock_clear_hotplug - Clear flag MEMBLOCK_HOTPLUG for a specified region.
732 * @base: the base phys addr of the region
733 * @size: the size of the region
735 * This function isolates region [@base, @base + @size), and clear flag
736 * MEMBLOCK_HOTPLUG for the isolated regions.
738 * Return 0 on succees, -errno on failure.
740 int __init_memblock memblock_clear_hotplug(phys_addr_t base, phys_addr_t size)
742 struct memblock_type *type = &memblock.memory;
743 int i, ret, start_rgn, end_rgn;
745 ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
749 for (i = start_rgn; i < end_rgn; i++)
750 memblock_clear_region_flags(&type->regions[i],
753 memblock_merge_regions(type);
758 * __next_free_mem_range - next function for for_each_free_mem_range()
759 * @idx: pointer to u64 loop variable
760 * @nid: node selector, %NUMA_NO_NODE for all nodes
761 * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
762 * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
763 * @out_nid: ptr to int for nid of the range, can be %NULL
765 * Find the first free area from *@idx which matches @nid, fill the out
766 * parameters, and update *@idx for the next iteration. The lower 32bit of
767 * *@idx contains index into memory region and the upper 32bit indexes the
768 * areas before each reserved region. For example, if reserved regions
769 * look like the following,
771 * 0:[0-16), 1:[32-48), 2:[128-130)
773 * The upper 32bit indexes the following regions.
775 * 0:[0-0), 1:[16-32), 2:[48-128), 3:[130-MAX)
777 * As both region arrays are sorted, the function advances the two indices
778 * in lockstep and returns each intersection.
780 void __init_memblock __next_free_mem_range(u64 *idx, int nid,
781 phys_addr_t *out_start,
782 phys_addr_t *out_end, int *out_nid)
784 struct memblock_type *mem = &memblock.memory;
785 struct memblock_type *rsv = &memblock.reserved;
786 int mi = *idx & 0xffffffff;
788 bool check_node = (nid != NUMA_NO_NODE) && (nid != MAX_NUMNODES);
790 if (nid == MAX_NUMNODES)
791 pr_warn_once("%s: Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n",
794 for ( ; mi < mem->cnt; mi++) {
795 struct memblock_region *m = &mem->regions[mi];
796 phys_addr_t m_start = m->base;
797 phys_addr_t m_end = m->base + m->size;
799 /* only memory regions are associated with nodes, check it */
800 if (check_node && nid != memblock_get_region_node(m))
803 /* scan areas before each reservation for intersection */
804 for ( ; ri < rsv->cnt + 1; ri++) {
805 struct memblock_region *r = &rsv->regions[ri];
806 phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
807 phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
809 /* if ri advanced past mi, break out to advance mi */
810 if (r_start >= m_end)
812 /* if the two regions intersect, we're done */
813 if (m_start < r_end) {
815 *out_start = max(m_start, r_start);
817 *out_end = min(m_end, r_end);
819 *out_nid = memblock_get_region_node(m);
821 * The region which ends first is advanced
822 * for the next iteration.
828 *idx = (u32)mi | (u64)ri << 32;
834 /* signal end of iteration */
839 * __next_free_mem_range_rev - next function for for_each_free_mem_range_reverse()
840 * @idx: pointer to u64 loop variable
841 * @nid: nid: node selector, %NUMA_NO_NODE for all nodes
842 * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
843 * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
844 * @out_nid: ptr to int for nid of the range, can be %NULL
846 * Reverse of __next_free_mem_range().
848 * Linux kernel cannot migrate pages used by itself. Memory hotplug users won't
849 * be able to hot-remove hotpluggable memory used by the kernel. So this
850 * function skip hotpluggable regions if needed when allocating memory for the
853 void __init_memblock __next_free_mem_range_rev(u64 *idx, int nid,
854 phys_addr_t *out_start,
855 phys_addr_t *out_end, int *out_nid)
857 struct memblock_type *mem = &memblock.memory;
858 struct memblock_type *rsv = &memblock.reserved;
859 int mi = *idx & 0xffffffff;
861 bool check_node = (nid != NUMA_NO_NODE) && (nid != MAX_NUMNODES);
863 if (nid == MAX_NUMNODES)
864 pr_warn_once("%s: Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n",
867 if (*idx == (u64)ULLONG_MAX) {
872 for ( ; mi >= 0; mi--) {
873 struct memblock_region *m = &mem->regions[mi];
874 phys_addr_t m_start = m->base;
875 phys_addr_t m_end = m->base + m->size;
877 /* only memory regions are associated with nodes, check it */
878 if (check_node && nid != memblock_get_region_node(m))
881 /* skip hotpluggable memory regions if needed */
882 if (movable_node_is_enabled() && memblock_is_hotpluggable(m))
885 /* scan areas before each reservation for intersection */
886 for ( ; ri >= 0; ri--) {
887 struct memblock_region *r = &rsv->regions[ri];
888 phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
889 phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
891 /* if ri advanced past mi, break out to advance mi */
892 if (r_end <= m_start)
894 /* if the two regions intersect, we're done */
895 if (m_end > r_start) {
897 *out_start = max(m_start, r_start);
899 *out_end = min(m_end, r_end);
901 *out_nid = memblock_get_region_node(m);
903 if (m_start >= r_start)
907 *idx = (u32)mi | (u64)ri << 32;
916 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
918 * Common iterator interface used to define for_each_mem_range().
920 void __init_memblock __next_mem_pfn_range(int *idx, int nid,
921 unsigned long *out_start_pfn,
922 unsigned long *out_end_pfn, int *out_nid)
924 struct memblock_type *type = &memblock.memory;
925 struct memblock_region *r;
927 while (++*idx < type->cnt) {
928 r = &type->regions[*idx];
930 if (PFN_UP(r->base) >= PFN_DOWN(r->base + r->size))
932 if (nid == MAX_NUMNODES || nid == r->nid)
935 if (*idx >= type->cnt) {
941 *out_start_pfn = PFN_UP(r->base);
943 *out_end_pfn = PFN_DOWN(r->base + r->size);
949 * memblock_set_node - set node ID on memblock regions
950 * @base: base of area to set node ID for
951 * @size: size of area to set node ID for
952 * @type: memblock type to set node ID for
953 * @nid: node ID to set
955 * Set the nid of memblock @type regions in [@base,@base+@size) to @nid.
956 * Regions which cross the area boundaries are split as necessary.
959 * 0 on success, -errno on failure.
961 int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
962 struct memblock_type *type, int nid)
964 int start_rgn, end_rgn;
967 ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
971 for (i = start_rgn; i < end_rgn; i++)
972 memblock_set_region_node(&type->regions[i], nid);
974 memblock_merge_regions(type);
977 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
979 static phys_addr_t __init memblock_alloc_base_nid(phys_addr_t size,
980 phys_addr_t align, phys_addr_t max_addr,
986 align = SMP_CACHE_BYTES;
988 /* align @size to avoid excessive fragmentation on reserved array */
989 size = round_up(size, align);
991 found = memblock_find_in_range_node(size, align, 0, max_addr, nid);
992 if (found && !memblock_reserve(found, size))
998 phys_addr_t __init memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int nid)
1000 return memblock_alloc_base_nid(size, align, MEMBLOCK_ALLOC_ACCESSIBLE, nid);
1003 phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
1005 return memblock_alloc_base_nid(size, align, max_addr, NUMA_NO_NODE);
1008 phys_addr_t __init memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
1012 alloc = __memblock_alloc_base(size, align, max_addr);
1015 panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
1016 (unsigned long long) size, (unsigned long long) max_addr);
1021 phys_addr_t __init memblock_alloc(phys_addr_t size, phys_addr_t align)
1023 return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
1026 phys_addr_t __init memblock_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
1028 phys_addr_t res = memblock_alloc_nid(size, align, nid);
1032 return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
1036 * memblock_virt_alloc_internal - allocate boot memory block
1037 * @size: size of memory block to be allocated in bytes
1038 * @align: alignment of the region and block's size
1039 * @min_addr: the lower bound of the memory region to allocate (phys address)
1040 * @max_addr: the upper bound of the memory region to allocate (phys address)
1041 * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1043 * The @min_addr limit is dropped if it can not be satisfied and the allocation
1044 * will fall back to memory below @min_addr. Also, allocation may fall back
1045 * to any node in the system if the specified node can not
1046 * hold the requested memory.
1048 * The allocation is performed from memory region limited by
1049 * memblock.current_limit if @max_addr == %BOOTMEM_ALLOC_ACCESSIBLE.
1051 * The memory block is aligned on SMP_CACHE_BYTES if @align == 0.
1053 * The phys address of allocated boot memory block is converted to virtual and
1054 * allocated memory is reset to 0.
1056 * In addition, function sets the min_count to 0 using kmemleak_alloc for
1057 * allocated boot memory block, so that it is never reported as leaks.
1060 * Virtual address of allocated memory block on success, NULL on failure.
1062 static void * __init memblock_virt_alloc_internal(
1063 phys_addr_t size, phys_addr_t align,
1064 phys_addr_t min_addr, phys_addr_t max_addr,
1070 if (nid == MAX_NUMNODES)
1071 pr_warn("%s: usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE\n",
1075 * Detect any accidental use of these APIs after slab is ready, as at
1076 * this moment memblock may be deinitialized already and its
1077 * internal data may be destroyed (after execution of free_all_bootmem)
1079 if (WARN_ON_ONCE(slab_is_available()))
1080 return kzalloc_node(size, GFP_NOWAIT, nid);
1083 align = SMP_CACHE_BYTES;
1085 /* align @size to avoid excessive fragmentation on reserved array */
1086 size = round_up(size, align);
1089 alloc = memblock_find_in_range_node(size, align, min_addr, max_addr,
1094 if (nid != NUMA_NO_NODE) {
1095 alloc = memblock_find_in_range_node(size, align, min_addr,
1096 max_addr, NUMA_NO_NODE);
1109 memblock_reserve(alloc, size);
1110 ptr = phys_to_virt(alloc);
1111 memset(ptr, 0, size);
1114 * The min_count is set to 0 so that bootmem allocated blocks
1115 * are never reported as leaks. This is because many of these blocks
1116 * are only referred via the physical address which is not
1117 * looked up by kmemleak.
1119 kmemleak_alloc(ptr, size, 0, 0);
1128 * memblock_virt_alloc_try_nid_nopanic - allocate boot memory block
1129 * @size: size of memory block to be allocated in bytes
1130 * @align: alignment of the region and block's size
1131 * @min_addr: the lower bound of the memory region from where the allocation
1132 * is preferred (phys address)
1133 * @max_addr: the upper bound of the memory region from where the allocation
1134 * is preferred (phys address), or %BOOTMEM_ALLOC_ACCESSIBLE to
1135 * allocate only from memory limited by memblock.current_limit value
1136 * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1138 * Public version of _memblock_virt_alloc_try_nid_nopanic() which provides
1139 * additional debug information (including caller info), if enabled.
1142 * Virtual address of allocated memory block on success, NULL on failure.
1144 void * __init memblock_virt_alloc_try_nid_nopanic(
1145 phys_addr_t size, phys_addr_t align,
1146 phys_addr_t min_addr, phys_addr_t max_addr,
1149 memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=0x%llx max_addr=0x%llx %pF\n",
1150 __func__, (u64)size, (u64)align, nid, (u64)min_addr,
1151 (u64)max_addr, (void *)_RET_IP_);
1152 return memblock_virt_alloc_internal(size, align, min_addr,
1157 * memblock_virt_alloc_try_nid - allocate boot memory block with panicking
1158 * @size: size of memory block to be allocated in bytes
1159 * @align: alignment of the region and block's size
1160 * @min_addr: the lower bound of the memory region from where the allocation
1161 * is preferred (phys address)
1162 * @max_addr: the upper bound of the memory region from where the allocation
1163 * is preferred (phys address), or %BOOTMEM_ALLOC_ACCESSIBLE to
1164 * allocate only from memory limited by memblock.current_limit value
1165 * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
1167 * Public panicking version of _memblock_virt_alloc_try_nid_nopanic()
1168 * which provides debug information (including caller info), if enabled,
1169 * and panics if the request can not be satisfied.
1172 * Virtual address of allocated memory block on success, NULL on failure.
1174 void * __init memblock_virt_alloc_try_nid(
1175 phys_addr_t size, phys_addr_t align,
1176 phys_addr_t min_addr, phys_addr_t max_addr,
1181 memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=0x%llx max_addr=0x%llx %pF\n",
1182 __func__, (u64)size, (u64)align, nid, (u64)min_addr,
1183 (u64)max_addr, (void *)_RET_IP_);
1184 ptr = memblock_virt_alloc_internal(size, align,
1185 min_addr, max_addr, nid);
1189 panic("%s: Failed to allocate %llu bytes align=0x%llx nid=%d from=0x%llx max_addr=0x%llx\n",
1190 __func__, (u64)size, (u64)align, nid, (u64)min_addr,
1196 * __memblock_free_early - free boot memory block
1197 * @base: phys starting address of the boot memory block
1198 * @size: size of the boot memory block in bytes
1200 * Free boot memory block previously allocated by memblock_virt_alloc_xx() API.
1201 * The freeing memory will not be released to the buddy allocator.
1203 void __init __memblock_free_early(phys_addr_t base, phys_addr_t size)
1205 memblock_dbg("%s: [%#016llx-%#016llx] %pF\n",
1206 __func__, (u64)base, (u64)base + size - 1,
1208 kmemleak_free_part(__va(base), size);
1209 __memblock_remove(&memblock.reserved, base, size);
1213 * __memblock_free_late - free bootmem block pages directly to buddy allocator
1214 * @addr: phys starting address of the boot memory block
1215 * @size: size of the boot memory block in bytes
1217 * This is only useful when the bootmem allocator has already been torn
1218 * down, but we are still initializing the system. Pages are released directly
1219 * to the buddy allocator, no bootmem metadata is updated because it is gone.
1221 void __init __memblock_free_late(phys_addr_t base, phys_addr_t size)
1225 memblock_dbg("%s: [%#016llx-%#016llx] %pF\n",
1226 __func__, (u64)base, (u64)base + size - 1,
1228 kmemleak_free_part(__va(base), size);
1229 cursor = PFN_UP(base);
1230 end = PFN_DOWN(base + size);
1232 for (; cursor < end; cursor++) {
1233 __free_pages_bootmem(pfn_to_page(cursor), 0);
1239 * Remaining API functions
1242 phys_addr_t __init memblock_phys_mem_size(void)
1244 return memblock.memory.total_size;
1247 phys_addr_t __init memblock_mem_size(unsigned long limit_pfn)
1249 unsigned long pages = 0;
1250 struct memblock_region *r;
1251 unsigned long start_pfn, end_pfn;
1253 for_each_memblock(memory, r) {
1254 start_pfn = memblock_region_memory_base_pfn(r);
1255 end_pfn = memblock_region_memory_end_pfn(r);
1256 start_pfn = min_t(unsigned long, start_pfn, limit_pfn);
1257 end_pfn = min_t(unsigned long, end_pfn, limit_pfn);
1258 pages += end_pfn - start_pfn;
1261 return (phys_addr_t)pages << PAGE_SHIFT;
1264 /* lowest address */
1265 phys_addr_t __init_memblock memblock_start_of_DRAM(void)
1267 return memblock.memory.regions[0].base;
1270 phys_addr_t __init_memblock memblock_end_of_DRAM(void)
1272 int idx = memblock.memory.cnt - 1;
1274 return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
1277 void __init memblock_enforce_memory_limit(phys_addr_t limit)
1280 phys_addr_t max_addr = (phys_addr_t)ULLONG_MAX;
1285 /* find out max address */
1286 for (i = 0; i < memblock.memory.cnt; i++) {
1287 struct memblock_region *r = &memblock.memory.regions[i];
1289 if (limit <= r->size) {
1290 max_addr = r->base + limit;
1296 /* truncate both memory and reserved regions */
1297 __memblock_remove(&memblock.memory, max_addr, (phys_addr_t)ULLONG_MAX);
1298 __memblock_remove(&memblock.reserved, max_addr, (phys_addr_t)ULLONG_MAX);
1301 static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
1303 unsigned int left = 0, right = type->cnt;
1306 unsigned int mid = (right + left) / 2;
1308 if (addr < type->regions[mid].base)
1310 else if (addr >= (type->regions[mid].base +
1311 type->regions[mid].size))
1315 } while (left < right);
1319 int __init memblock_is_reserved(phys_addr_t addr)
1321 return memblock_search(&memblock.reserved, addr) != -1;
1324 int __init_memblock memblock_is_memory(phys_addr_t addr)
1326 return memblock_search(&memblock.memory, addr) != -1;
1329 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
1330 int __init_memblock memblock_search_pfn_nid(unsigned long pfn,
1331 unsigned long *start_pfn, unsigned long *end_pfn)
1333 struct memblock_type *type = &memblock.memory;
1334 int mid = memblock_search(type, (phys_addr_t)pfn << PAGE_SHIFT);
1339 *start_pfn = type->regions[mid].base >> PAGE_SHIFT;
1340 *end_pfn = (type->regions[mid].base + type->regions[mid].size)
1343 return type->regions[mid].nid;
1348 * memblock_is_region_memory - check if a region is a subset of memory
1349 * @base: base of region to check
1350 * @size: size of region to check
1352 * Check if the region [@base, @base+@size) is a subset of a memory block.
1355 * 0 if false, non-zero if true
1357 int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
1359 int idx = memblock_search(&memblock.memory, base);
1360 phys_addr_t end = base + memblock_cap_size(base, &size);
1364 return memblock.memory.regions[idx].base <= base &&
1365 (memblock.memory.regions[idx].base +
1366 memblock.memory.regions[idx].size) >= end;
1370 * memblock_is_region_reserved - check if a region intersects reserved memory
1371 * @base: base of region to check
1372 * @size: size of region to check
1374 * Check if the region [@base, @base+@size) intersects a reserved memory block.
1377 * 0 if false, non-zero if true
1379 int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
1381 memblock_cap_size(base, &size);
1382 return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;
1385 void __init_memblock memblock_trim_memory(phys_addr_t align)
1388 phys_addr_t start, end, orig_start, orig_end;
1389 struct memblock_type *mem = &memblock.memory;
1391 for (i = 0; i < mem->cnt; i++) {
1392 orig_start = mem->regions[i].base;
1393 orig_end = mem->regions[i].base + mem->regions[i].size;
1394 start = round_up(orig_start, align);
1395 end = round_down(orig_end, align);
1397 if (start == orig_start && end == orig_end)
1401 mem->regions[i].base = start;
1402 mem->regions[i].size = end - start;
1404 memblock_remove_region(mem, i);
1410 void __init_memblock memblock_set_current_limit(phys_addr_t limit)
1412 memblock.current_limit = limit;
1415 static void __init_memblock memblock_dump(struct memblock_type *type, char *name)
1417 unsigned long long base, size;
1418 unsigned long flags;
1421 pr_info(" %s.cnt = 0x%lx\n", name, type->cnt);
1423 for (i = 0; i < type->cnt; i++) {
1424 struct memblock_region *rgn = &type->regions[i];
1425 char nid_buf[32] = "";
1430 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
1431 if (memblock_get_region_node(rgn) != MAX_NUMNODES)
1432 snprintf(nid_buf, sizeof(nid_buf), " on node %d",
1433 memblock_get_region_node(rgn));
1435 pr_info(" %s[%#x]\t[%#016llx-%#016llx], %#llx bytes%s flags: %#lx\n",
1436 name, i, base, base + size - 1, size, nid_buf, flags);
1440 void __init_memblock __memblock_dump_all(void)
1442 pr_info("MEMBLOCK configuration:\n");
1443 pr_info(" memory size = %#llx reserved size = %#llx\n",
1444 (unsigned long long)memblock.memory.total_size,
1445 (unsigned long long)memblock.reserved.total_size);
1447 memblock_dump(&memblock.memory, "memory");
1448 memblock_dump(&memblock.reserved, "reserved");
1451 void __init memblock_allow_resize(void)
1453 memblock_can_resize = 1;
1456 static int __init early_memblock(char *p)
1458 if (p && strstr(p, "debug"))
1462 early_param("memblock", early_memblock);
1464 #if defined(CONFIG_DEBUG_FS) && !defined(CONFIG_ARCH_DISCARD_MEMBLOCK)
1466 static int memblock_debug_show(struct seq_file *m, void *private)
1468 struct memblock_type *type = m->private;
1469 struct memblock_region *reg;
1472 for (i = 0; i < type->cnt; i++) {
1473 reg = &type->regions[i];
1474 seq_printf(m, "%4d: ", i);
1475 if (sizeof(phys_addr_t) == 4)
1476 seq_printf(m, "0x%08lx..0x%08lx\n",
1477 (unsigned long)reg->base,
1478 (unsigned long)(reg->base + reg->size - 1));
1480 seq_printf(m, "0x%016llx..0x%016llx\n",
1481 (unsigned long long)reg->base,
1482 (unsigned long long)(reg->base + reg->size - 1));
1488 static int memblock_debug_open(struct inode *inode, struct file *file)
1490 return single_open(file, memblock_debug_show, inode->i_private);
1493 static const struct file_operations memblock_debug_fops = {
1494 .open = memblock_debug_open,
1496 .llseek = seq_lseek,
1497 .release = single_release,
1500 static int __init memblock_init_debugfs(void)
1502 struct dentry *root = debugfs_create_dir("memblock", NULL);
1505 debugfs_create_file("memory", S_IRUGO, root, &memblock.memory, &memblock_debug_fops);
1506 debugfs_create_file("reserved", S_IRUGO, root, &memblock.reserved, &memblock_debug_fops);
1510 __initcall(memblock_init_debugfs);
1512 #endif /* CONFIG_DEBUG_FS */