2 * bootmem - A boot-time physical memory allocator and configurator
4 * Copyright (C) 1999 Ingo Molnar
5 * 1999 Kanoj Sarcar, SGI
8 * Access to this subsystem has to be serialized externally (which is true
9 * for the boot process anyway).
11 #include <linux/init.h>
12 #include <linux/pfn.h>
13 #include <linux/slab.h>
14 #include <linux/bootmem.h>
15 #include <linux/export.h>
16 #include <linux/kmemleak.h>
17 #include <linux/range.h>
18 #include <linux/memblock.h>
22 #include <asm/processor.h>
26 #ifndef CONFIG_NEED_MULTIPLE_NODES
27 struct pglist_data __refdata contig_page_data
= {
28 .bdata
= &bootmem_node_data
[0]
30 EXPORT_SYMBOL(contig_page_data
);
33 unsigned long max_low_pfn
;
34 unsigned long min_low_pfn
;
35 unsigned long max_pfn
;
37 bootmem_data_t bootmem_node_data
[MAX_NUMNODES
] __initdata
;
39 static struct list_head bdata_list __initdata
= LIST_HEAD_INIT(bdata_list
);
41 static int bootmem_debug
;
43 static int __init
bootmem_debug_setup(char *buf
)
48 early_param("bootmem_debug", bootmem_debug_setup
);
50 #define bdebug(fmt, args...) ({ \
51 if (unlikely(bootmem_debug)) \
57 static unsigned long __init
bootmap_bytes(unsigned long pages
)
59 unsigned long bytes
= (pages
+ 7) / 8;
61 return ALIGN(bytes
, sizeof(long));
65 * bootmem_bootmap_pages - calculate bitmap size in pages
66 * @pages: number of pages the bitmap has to represent
68 unsigned long __init
bootmem_bootmap_pages(unsigned long pages
)
70 unsigned long bytes
= bootmap_bytes(pages
);
72 return PAGE_ALIGN(bytes
) >> PAGE_SHIFT
;
78 static void __init
link_bootmem(bootmem_data_t
*bdata
)
80 struct list_head
*iter
;
82 list_for_each(iter
, &bdata_list
) {
85 ent
= list_entry(iter
, bootmem_data_t
, list
);
86 if (bdata
->node_min_pfn
< ent
->node_min_pfn
)
89 list_add_tail(&bdata
->list
, iter
);
93 * Called once to set up the allocator itself.
95 static unsigned long __init
init_bootmem_core(bootmem_data_t
*bdata
,
96 unsigned long mapstart
, unsigned long start
, unsigned long end
)
98 unsigned long mapsize
;
100 mminit_validate_memmodel_limits(&start
, &end
);
101 bdata
->node_bootmem_map
= phys_to_virt(PFN_PHYS(mapstart
));
102 bdata
->node_min_pfn
= start
;
103 bdata
->node_low_pfn
= end
;
107 * Initially all pages are reserved - setup_arch() has to
108 * register free RAM areas explicitly.
110 mapsize
= bootmap_bytes(end
- start
);
111 memset(bdata
->node_bootmem_map
, 0xff, mapsize
);
113 bdebug("nid=%td start=%lx map=%lx end=%lx mapsize=%lx\n",
114 bdata
- bootmem_node_data
, start
, mapstart
, end
, mapsize
);
120 * init_bootmem_node - register a node as boot memory
121 * @pgdat: node to register
122 * @freepfn: pfn where the bitmap for this node is to be placed
123 * @startpfn: first pfn on the node
124 * @endpfn: first pfn after the node
126 * Returns the number of bytes needed to hold the bitmap for this node.
128 unsigned long __init
init_bootmem_node(pg_data_t
*pgdat
, unsigned long freepfn
,
129 unsigned long startpfn
, unsigned long endpfn
)
131 return init_bootmem_core(pgdat
->bdata
, freepfn
, startpfn
, endpfn
);
135 * init_bootmem - register boot memory
136 * @start: pfn where the bitmap is to be placed
137 * @pages: number of available physical pages
139 * Returns the number of bytes needed to hold the bitmap.
141 unsigned long __init
init_bootmem(unsigned long start
, unsigned long pages
)
145 return init_bootmem_core(NODE_DATA(0)->bdata
, start
, 0, pages
);
149 * free_bootmem_late - free bootmem pages directly to page allocator
150 * @addr: starting address of the range
151 * @size: size of the range in bytes
153 * This is only useful when the bootmem allocator has already been torn
154 * down, but we are still initializing the system. Pages are given directly
155 * to the page allocator, no bootmem metadata is updated because it is gone.
157 void __init
free_bootmem_late(unsigned long addr
, unsigned long size
)
159 unsigned long cursor
, end
;
161 kmemleak_free_part(__va(addr
), size
);
163 cursor
= PFN_UP(addr
);
164 end
= PFN_DOWN(addr
+ size
);
166 for (; cursor
< end
; cursor
++) {
167 __free_pages_bootmem(pfn_to_page(cursor
), 0);
172 static unsigned long __init
free_all_bootmem_core(bootmem_data_t
*bdata
)
176 unsigned long start
, end
, pages
, count
= 0;
178 if (!bdata
->node_bootmem_map
)
181 start
= bdata
->node_min_pfn
;
182 end
= bdata
->node_low_pfn
;
185 * If the start is aligned to the machines wordsize, we might
186 * be able to free pages in bulks of that order.
188 aligned
= !(start
& (BITS_PER_LONG
- 1));
190 bdebug("nid=%td start=%lx end=%lx aligned=%d\n",
191 bdata
- bootmem_node_data
, start
, end
, aligned
);
193 while (start
< end
) {
194 unsigned long *map
, idx
, vec
;
196 map
= bdata
->node_bootmem_map
;
197 idx
= start
- bdata
->node_min_pfn
;
198 vec
= ~map
[idx
/ BITS_PER_LONG
];
200 if (aligned
&& vec
== ~0UL && start
+ BITS_PER_LONG
< end
) {
201 int order
= ilog2(BITS_PER_LONG
);
203 __free_pages_bootmem(pfn_to_page(start
), order
);
204 count
+= BITS_PER_LONG
;
206 unsigned long off
= 0;
208 while (vec
&& off
< BITS_PER_LONG
) {
210 page
= pfn_to_page(start
+ off
);
211 __free_pages_bootmem(page
, 0);
218 start
+= BITS_PER_LONG
;
221 page
= virt_to_page(bdata
->node_bootmem_map
);
222 pages
= bdata
->node_low_pfn
- bdata
->node_min_pfn
;
223 pages
= bootmem_bootmap_pages(pages
);
226 __free_pages_bootmem(page
++, 0);
228 bdebug("nid=%td released=%lx\n", bdata
- bootmem_node_data
, count
);
234 * free_all_bootmem_node - release a node's free pages to the buddy allocator
235 * @pgdat: node to be released
237 * Returns the number of pages actually released.
239 unsigned long __init
free_all_bootmem_node(pg_data_t
*pgdat
)
241 register_page_bootmem_info_node(pgdat
);
242 return free_all_bootmem_core(pgdat
->bdata
);
246 * free_all_bootmem - release free pages to the buddy allocator
248 * Returns the number of pages actually released.
250 unsigned long __init
free_all_bootmem(void)
252 unsigned long total_pages
= 0;
253 bootmem_data_t
*bdata
;
255 list_for_each_entry(bdata
, &bdata_list
, list
)
256 total_pages
+= free_all_bootmem_core(bdata
);
261 static void __init
__free(bootmem_data_t
*bdata
,
262 unsigned long sidx
, unsigned long eidx
)
266 bdebug("nid=%td start=%lx end=%lx\n", bdata
- bootmem_node_data
,
267 sidx
+ bdata
->node_min_pfn
,
268 eidx
+ bdata
->node_min_pfn
);
270 if (bdata
->hint_idx
> sidx
)
271 bdata
->hint_idx
= sidx
;
273 for (idx
= sidx
; idx
< eidx
; idx
++)
274 if (!test_and_clear_bit(idx
, bdata
->node_bootmem_map
))
278 static int __init
__reserve(bootmem_data_t
*bdata
, unsigned long sidx
,
279 unsigned long eidx
, int flags
)
282 int exclusive
= flags
& BOOTMEM_EXCLUSIVE
;
284 bdebug("nid=%td start=%lx end=%lx flags=%x\n",
285 bdata
- bootmem_node_data
,
286 sidx
+ bdata
->node_min_pfn
,
287 eidx
+ bdata
->node_min_pfn
,
290 for (idx
= sidx
; idx
< eidx
; idx
++)
291 if (test_and_set_bit(idx
, bdata
->node_bootmem_map
)) {
293 __free(bdata
, sidx
, idx
);
296 bdebug("silent double reserve of PFN %lx\n",
297 idx
+ bdata
->node_min_pfn
);
302 static int __init
mark_bootmem_node(bootmem_data_t
*bdata
,
303 unsigned long start
, unsigned long end
,
304 int reserve
, int flags
)
306 unsigned long sidx
, eidx
;
308 bdebug("nid=%td start=%lx end=%lx reserve=%d flags=%x\n",
309 bdata
- bootmem_node_data
, start
, end
, reserve
, flags
);
311 BUG_ON(start
< bdata
->node_min_pfn
);
312 BUG_ON(end
> bdata
->node_low_pfn
);
314 sidx
= start
- bdata
->node_min_pfn
;
315 eidx
= end
- bdata
->node_min_pfn
;
318 return __reserve(bdata
, sidx
, eidx
, flags
);
320 __free(bdata
, sidx
, eidx
);
324 static int __init
mark_bootmem(unsigned long start
, unsigned long end
,
325 int reserve
, int flags
)
328 bootmem_data_t
*bdata
;
331 list_for_each_entry(bdata
, &bdata_list
, list
) {
335 if (pos
< bdata
->node_min_pfn
||
336 pos
>= bdata
->node_low_pfn
) {
337 BUG_ON(pos
!= start
);
341 max
= min(bdata
->node_low_pfn
, end
);
343 err
= mark_bootmem_node(bdata
, pos
, max
, reserve
, flags
);
344 if (reserve
&& err
) {
345 mark_bootmem(start
, pos
, 0, 0);
351 pos
= bdata
->node_low_pfn
;
357 * free_bootmem_node - mark a page range as usable
358 * @pgdat: node the range resides on
359 * @physaddr: starting address of the range
360 * @size: size of the range in bytes
362 * Partial pages will be considered reserved and left as they are.
364 * The range must reside completely on the specified node.
366 void __init
free_bootmem_node(pg_data_t
*pgdat
, unsigned long physaddr
,
369 unsigned long start
, end
;
371 kmemleak_free_part(__va(physaddr
), size
);
373 start
= PFN_UP(physaddr
);
374 end
= PFN_DOWN(physaddr
+ size
);
376 mark_bootmem_node(pgdat
->bdata
, start
, end
, 0, 0);
380 * free_bootmem - mark a page range as usable
381 * @addr: starting address of the range
382 * @size: size of the range in bytes
384 * Partial pages will be considered reserved and left as they are.
386 * The range must be contiguous but may span node boundaries.
388 void __init
free_bootmem(unsigned long addr
, unsigned long size
)
390 unsigned long start
, end
;
392 kmemleak_free_part(__va(addr
), size
);
394 start
= PFN_UP(addr
);
395 end
= PFN_DOWN(addr
+ size
);
397 mark_bootmem(start
, end
, 0, 0);
401 * reserve_bootmem_node - mark a page range as reserved
402 * @pgdat: node the range resides on
403 * @physaddr: starting address of the range
404 * @size: size of the range in bytes
405 * @flags: reservation flags (see linux/bootmem.h)
407 * Partial pages will be reserved.
409 * The range must reside completely on the specified node.
411 int __init
reserve_bootmem_node(pg_data_t
*pgdat
, unsigned long physaddr
,
412 unsigned long size
, int flags
)
414 unsigned long start
, end
;
416 start
= PFN_DOWN(physaddr
);
417 end
= PFN_UP(physaddr
+ size
);
419 return mark_bootmem_node(pgdat
->bdata
, start
, end
, 1, flags
);
423 * reserve_bootmem - mark a page range as usable
424 * @addr: starting address of the range
425 * @size: size of the range in bytes
426 * @flags: reservation flags (see linux/bootmem.h)
428 * Partial pages will be reserved.
430 * The range must be contiguous but may span node boundaries.
432 int __init
reserve_bootmem(unsigned long addr
, unsigned long size
,
435 unsigned long start
, end
;
437 start
= PFN_DOWN(addr
);
438 end
= PFN_UP(addr
+ size
);
440 return mark_bootmem(start
, end
, 1, flags
);
443 int __weak __init
reserve_bootmem_generic(unsigned long phys
, unsigned long len
,
446 return reserve_bootmem(phys
, len
, flags
);
449 static unsigned long __init
align_idx(struct bootmem_data
*bdata
,
450 unsigned long idx
, unsigned long step
)
452 unsigned long base
= bdata
->node_min_pfn
;
455 * Align the index with respect to the node start so that the
456 * combination of both satisfies the requested alignment.
459 return ALIGN(base
+ idx
, step
) - base
;
462 static unsigned long __init
align_off(struct bootmem_data
*bdata
,
463 unsigned long off
, unsigned long align
)
465 unsigned long base
= PFN_PHYS(bdata
->node_min_pfn
);
467 /* Same as align_idx for byte offsets */
469 return ALIGN(base
+ off
, align
) - base
;
472 static void * __init
alloc_bootmem_core(struct bootmem_data
*bdata
,
473 unsigned long size
, unsigned long align
,
474 unsigned long goal
, unsigned long limit
)
476 unsigned long fallback
= 0;
477 unsigned long min
, max
, start
, sidx
, midx
, step
;
479 bdebug("nid=%td size=%lx [%lu pages] align=%lx goal=%lx limit=%lx\n",
480 bdata
- bootmem_node_data
, size
, PAGE_ALIGN(size
) >> PAGE_SHIFT
,
484 BUG_ON(align
& (align
- 1));
485 BUG_ON(limit
&& goal
+ size
> limit
);
487 if (!bdata
->node_bootmem_map
)
490 min
= bdata
->node_min_pfn
;
491 max
= bdata
->node_low_pfn
;
494 limit
>>= PAGE_SHIFT
;
496 if (limit
&& max
> limit
)
501 step
= max(align
>> PAGE_SHIFT
, 1UL);
503 if (goal
&& min
< goal
&& goal
< max
)
504 start
= ALIGN(goal
, step
);
506 start
= ALIGN(min
, step
);
508 sidx
= start
- bdata
->node_min_pfn
;
509 midx
= max
- bdata
->node_min_pfn
;
511 if (bdata
->hint_idx
> sidx
) {
513 * Handle the valid case of sidx being zero and still
514 * catch the fallback below.
517 sidx
= align_idx(bdata
, bdata
->hint_idx
, step
);
523 unsigned long eidx
, i
, start_off
, end_off
;
525 sidx
= find_next_zero_bit(bdata
->node_bootmem_map
, midx
, sidx
);
526 sidx
= align_idx(bdata
, sidx
, step
);
527 eidx
= sidx
+ PFN_UP(size
);
529 if (sidx
>= midx
|| eidx
> midx
)
532 for (i
= sidx
; i
< eidx
; i
++)
533 if (test_bit(i
, bdata
->node_bootmem_map
)) {
534 sidx
= align_idx(bdata
, i
, step
);
540 if (bdata
->last_end_off
& (PAGE_SIZE
- 1) &&
541 PFN_DOWN(bdata
->last_end_off
) + 1 == sidx
)
542 start_off
= align_off(bdata
, bdata
->last_end_off
, align
);
544 start_off
= PFN_PHYS(sidx
);
546 merge
= PFN_DOWN(start_off
) < sidx
;
547 end_off
= start_off
+ size
;
549 bdata
->last_end_off
= end_off
;
550 bdata
->hint_idx
= PFN_UP(end_off
);
553 * Reserve the area now:
555 if (__reserve(bdata
, PFN_DOWN(start_off
) + merge
,
556 PFN_UP(end_off
), BOOTMEM_EXCLUSIVE
))
559 region
= phys_to_virt(PFN_PHYS(bdata
->node_min_pfn
) +
561 memset(region
, 0, size
);
563 * The min_count is set to 0 so that bootmem allocated blocks
564 * are never reported as leaks.
566 kmemleak_alloc(region
, size
, 0, 0);
571 sidx
= align_idx(bdata
, fallback
- 1, step
);
579 static void * __init
alloc_arch_preferred_bootmem(bootmem_data_t
*bdata
,
580 unsigned long size
, unsigned long align
,
581 unsigned long goal
, unsigned long limit
)
583 if (WARN_ON_ONCE(slab_is_available()))
584 return kzalloc(size
, GFP_NOWAIT
);
586 #ifdef CONFIG_HAVE_ARCH_BOOTMEM
588 bootmem_data_t
*p_bdata
;
590 p_bdata
= bootmem_arch_preferred_node(bdata
, size
, align
,
593 return alloc_bootmem_core(p_bdata
, size
, align
,
600 static void * __init
___alloc_bootmem_nopanic(unsigned long size
,
605 bootmem_data_t
*bdata
;
609 region
= alloc_arch_preferred_bootmem(NULL
, size
, align
, goal
, limit
);
613 list_for_each_entry(bdata
, &bdata_list
, list
) {
614 if (goal
&& bdata
->node_low_pfn
<= PFN_DOWN(goal
))
616 if (limit
&& bdata
->node_min_pfn
>= PFN_DOWN(limit
))
619 region
= alloc_bootmem_core(bdata
, size
, align
, goal
, limit
);
633 * __alloc_bootmem_nopanic - allocate boot memory without panicking
634 * @size: size of the request in bytes
635 * @align: alignment of the region
636 * @goal: preferred starting address of the region
638 * The goal is dropped if it can not be satisfied and the allocation will
639 * fall back to memory below @goal.
641 * Allocation may happen on any node in the system.
643 * Returns NULL on failure.
645 void * __init
__alloc_bootmem_nopanic(unsigned long size
, unsigned long align
,
648 unsigned long limit
= 0;
650 return ___alloc_bootmem_nopanic(size
, align
, goal
, limit
);
653 static void * __init
___alloc_bootmem(unsigned long size
, unsigned long align
,
654 unsigned long goal
, unsigned long limit
)
656 void *mem
= ___alloc_bootmem_nopanic(size
, align
, goal
, limit
);
661 * Whoops, we cannot satisfy the allocation request.
663 printk(KERN_ALERT
"bootmem alloc of %lu bytes failed!\n", size
);
664 panic("Out of memory");
669 * __alloc_bootmem - allocate boot memory
670 * @size: size of the request in bytes
671 * @align: alignment of the region
672 * @goal: preferred starting address of the region
674 * The goal is dropped if it can not be satisfied and the allocation will
675 * fall back to memory below @goal.
677 * Allocation may happen on any node in the system.
679 * The function panics if the request can not be satisfied.
681 void * __init
__alloc_bootmem(unsigned long size
, unsigned long align
,
684 unsigned long limit
= 0;
686 return ___alloc_bootmem(size
, align
, goal
, limit
);
689 static void * __init
___alloc_bootmem_node(bootmem_data_t
*bdata
,
690 unsigned long size
, unsigned long align
,
691 unsigned long goal
, unsigned long limit
)
695 ptr
= alloc_arch_preferred_bootmem(bdata
, size
, align
, goal
, limit
);
699 ptr
= alloc_bootmem_core(bdata
, size
, align
, goal
, limit
);
703 return ___alloc_bootmem(size
, align
, goal
, limit
);
707 * __alloc_bootmem_node - allocate boot memory from a specific node
708 * @pgdat: node to allocate from
709 * @size: size of the request in bytes
710 * @align: alignment of the region
711 * @goal: preferred starting address of the region
713 * The goal is dropped if it can not be satisfied and the allocation will
714 * fall back to memory below @goal.
716 * Allocation may fall back to any node in the system if the specified node
717 * can not hold the requested memory.
719 * The function panics if the request can not be satisfied.
721 void * __init
__alloc_bootmem_node(pg_data_t
*pgdat
, unsigned long size
,
722 unsigned long align
, unsigned long goal
)
724 if (WARN_ON_ONCE(slab_is_available()))
725 return kzalloc_node(size
, GFP_NOWAIT
, pgdat
->node_id
);
727 return ___alloc_bootmem_node(pgdat
->bdata
, size
, align
, goal
, 0);
730 void * __init
__alloc_bootmem_node_high(pg_data_t
*pgdat
, unsigned long size
,
731 unsigned long align
, unsigned long goal
)
734 unsigned long end_pfn
;
736 if (WARN_ON_ONCE(slab_is_available()))
737 return kzalloc_node(size
, GFP_NOWAIT
, pgdat
->node_id
);
739 /* update goal according ...MAX_DMA32_PFN */
740 end_pfn
= pgdat
->node_start_pfn
+ pgdat
->node_spanned_pages
;
742 if (end_pfn
> MAX_DMA32_PFN
+ (128 >> (20 - PAGE_SHIFT
)) &&
743 (goal
>> PAGE_SHIFT
) < MAX_DMA32_PFN
) {
745 unsigned long new_goal
;
747 new_goal
= MAX_DMA32_PFN
<< PAGE_SHIFT
;
748 ptr
= alloc_bootmem_core(pgdat
->bdata
, size
, align
,
755 return __alloc_bootmem_node(pgdat
, size
, align
, goal
);
759 #ifdef CONFIG_SPARSEMEM
761 * alloc_bootmem_section - allocate boot memory from a specific section
762 * @size: size of the request in bytes
763 * @section_nr: sparse map section to allocate from
765 * Return NULL on failure.
767 void * __init
alloc_bootmem_section(unsigned long size
,
768 unsigned long section_nr
)
770 bootmem_data_t
*bdata
;
771 unsigned long pfn
, goal
;
773 pfn
= section_nr_to_pfn(section_nr
);
774 goal
= pfn
<< PAGE_SHIFT
;
775 bdata
= &bootmem_node_data
[early_pfn_to_nid(pfn
)];
777 return alloc_bootmem_core(bdata
, size
, SMP_CACHE_BYTES
, goal
, 0);
781 void * __init
__alloc_bootmem_node_nopanic(pg_data_t
*pgdat
, unsigned long size
,
782 unsigned long align
, unsigned long goal
)
786 if (WARN_ON_ONCE(slab_is_available()))
787 return kzalloc_node(size
, GFP_NOWAIT
, pgdat
->node_id
);
789 ptr
= alloc_arch_preferred_bootmem(pgdat
->bdata
, size
, align
, goal
, 0);
793 ptr
= alloc_bootmem_core(pgdat
->bdata
, size
, align
, goal
, 0);
797 return __alloc_bootmem_nopanic(size
, align
, goal
);
800 #ifndef ARCH_LOW_ADDRESS_LIMIT
801 #define ARCH_LOW_ADDRESS_LIMIT 0xffffffffUL
805 * __alloc_bootmem_low - allocate low boot memory
806 * @size: size of the request in bytes
807 * @align: alignment of the region
808 * @goal: preferred starting address of the region
810 * The goal is dropped if it can not be satisfied and the allocation will
811 * fall back to memory below @goal.
813 * Allocation may happen on any node in the system.
815 * The function panics if the request can not be satisfied.
817 void * __init
__alloc_bootmem_low(unsigned long size
, unsigned long align
,
820 return ___alloc_bootmem(size
, align
, goal
, ARCH_LOW_ADDRESS_LIMIT
);
824 * __alloc_bootmem_low_node - allocate low boot memory from a specific node
825 * @pgdat: node to allocate from
826 * @size: size of the request in bytes
827 * @align: alignment of the region
828 * @goal: preferred starting address of the region
830 * The goal is dropped if it can not be satisfied and the allocation will
831 * fall back to memory below @goal.
833 * Allocation may fall back to any node in the system if the specified node
834 * can not hold the requested memory.
836 * The function panics if the request can not be satisfied.
838 void * __init
__alloc_bootmem_low_node(pg_data_t
*pgdat
, unsigned long size
,
839 unsigned long align
, unsigned long goal
)
841 if (WARN_ON_ONCE(slab_is_available()))
842 return kzalloc_node(size
, GFP_NOWAIT
, pgdat
->node_id
);
844 return ___alloc_bootmem_node(pgdat
->bdata
, size
, align
,
845 goal
, ARCH_LOW_ADDRESS_LIMIT
);