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
= DIV_ROUND_UP(pages
, 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
)
175 unsigned long start
, end
, pages
, count
= 0;
177 if (!bdata
->node_bootmem_map
)
180 start
= bdata
->node_min_pfn
;
181 end
= bdata
->node_low_pfn
;
183 bdebug("nid=%td start=%lx end=%lx\n",
184 bdata
- bootmem_node_data
, start
, end
);
186 while (start
< end
) {
187 unsigned long *map
, idx
, vec
;
189 map
= bdata
->node_bootmem_map
;
190 idx
= start
- bdata
->node_min_pfn
;
191 vec
= ~map
[idx
/ BITS_PER_LONG
];
193 * If we have a properly aligned and fully unreserved
194 * BITS_PER_LONG block of pages in front of us, free
197 if (IS_ALIGNED(start
, BITS_PER_LONG
) && vec
== ~0UL) {
198 int order
= ilog2(BITS_PER_LONG
);
200 __free_pages_bootmem(pfn_to_page(start
), order
);
201 count
+= BITS_PER_LONG
;
202 start
+= BITS_PER_LONG
;
204 unsigned long off
= 0;
206 while (vec
&& off
< BITS_PER_LONG
) {
208 page
= pfn_to_page(start
+ off
);
209 __free_pages_bootmem(page
, 0);
215 start
= ALIGN(start
+ 1, BITS_PER_LONG
);
219 page
= virt_to_page(bdata
->node_bootmem_map
);
220 pages
= bdata
->node_low_pfn
- bdata
->node_min_pfn
;
221 pages
= bootmem_bootmap_pages(pages
);
224 __free_pages_bootmem(page
++, 0);
226 bdebug("nid=%td released=%lx\n", bdata
- bootmem_node_data
, count
);
232 * free_all_bootmem_node - release a node's free pages to the buddy allocator
233 * @pgdat: node to be released
235 * Returns the number of pages actually released.
237 unsigned long __init
free_all_bootmem_node(pg_data_t
*pgdat
)
239 register_page_bootmem_info_node(pgdat
);
240 return free_all_bootmem_core(pgdat
->bdata
);
244 * free_all_bootmem - release free pages to the buddy allocator
246 * Returns the number of pages actually released.
248 unsigned long __init
free_all_bootmem(void)
250 unsigned long total_pages
= 0;
251 bootmem_data_t
*bdata
;
253 list_for_each_entry(bdata
, &bdata_list
, list
)
254 total_pages
+= free_all_bootmem_core(bdata
);
259 static void __init
__free(bootmem_data_t
*bdata
,
260 unsigned long sidx
, unsigned long eidx
)
264 bdebug("nid=%td start=%lx end=%lx\n", bdata
- bootmem_node_data
,
265 sidx
+ bdata
->node_min_pfn
,
266 eidx
+ bdata
->node_min_pfn
);
268 if (bdata
->hint_idx
> sidx
)
269 bdata
->hint_idx
= sidx
;
271 for (idx
= sidx
; idx
< eidx
; idx
++)
272 if (!test_and_clear_bit(idx
, bdata
->node_bootmem_map
))
276 static int __init
__reserve(bootmem_data_t
*bdata
, unsigned long sidx
,
277 unsigned long eidx
, int flags
)
280 int exclusive
= flags
& BOOTMEM_EXCLUSIVE
;
282 bdebug("nid=%td start=%lx end=%lx flags=%x\n",
283 bdata
- bootmem_node_data
,
284 sidx
+ bdata
->node_min_pfn
,
285 eidx
+ bdata
->node_min_pfn
,
288 for (idx
= sidx
; idx
< eidx
; idx
++)
289 if (test_and_set_bit(idx
, bdata
->node_bootmem_map
)) {
291 __free(bdata
, sidx
, idx
);
294 bdebug("silent double reserve of PFN %lx\n",
295 idx
+ bdata
->node_min_pfn
);
300 static int __init
mark_bootmem_node(bootmem_data_t
*bdata
,
301 unsigned long start
, unsigned long end
,
302 int reserve
, int flags
)
304 unsigned long sidx
, eidx
;
306 bdebug("nid=%td start=%lx end=%lx reserve=%d flags=%x\n",
307 bdata
- bootmem_node_data
, start
, end
, reserve
, flags
);
309 BUG_ON(start
< bdata
->node_min_pfn
);
310 BUG_ON(end
> bdata
->node_low_pfn
);
312 sidx
= start
- bdata
->node_min_pfn
;
313 eidx
= end
- bdata
->node_min_pfn
;
316 return __reserve(bdata
, sidx
, eidx
, flags
);
318 __free(bdata
, sidx
, eidx
);
322 static int __init
mark_bootmem(unsigned long start
, unsigned long end
,
323 int reserve
, int flags
)
326 bootmem_data_t
*bdata
;
329 list_for_each_entry(bdata
, &bdata_list
, list
) {
333 if (pos
< bdata
->node_min_pfn
||
334 pos
>= bdata
->node_low_pfn
) {
335 BUG_ON(pos
!= start
);
339 max
= min(bdata
->node_low_pfn
, end
);
341 err
= mark_bootmem_node(bdata
, pos
, max
, reserve
, flags
);
342 if (reserve
&& err
) {
343 mark_bootmem(start
, pos
, 0, 0);
349 pos
= bdata
->node_low_pfn
;
355 * free_bootmem_node - mark a page range as usable
356 * @pgdat: node the range resides on
357 * @physaddr: starting address of the range
358 * @size: size of the range in bytes
360 * Partial pages will be considered reserved and left as they are.
362 * The range must reside completely on the specified node.
364 void __init
free_bootmem_node(pg_data_t
*pgdat
, unsigned long physaddr
,
367 unsigned long start
, end
;
369 kmemleak_free_part(__va(physaddr
), size
);
371 start
= PFN_UP(physaddr
);
372 end
= PFN_DOWN(physaddr
+ size
);
374 mark_bootmem_node(pgdat
->bdata
, start
, end
, 0, 0);
378 * free_bootmem - mark a page range as usable
379 * @addr: starting address of the range
380 * @size: size of the range in bytes
382 * Partial pages will be considered reserved and left as they are.
384 * The range must be contiguous but may span node boundaries.
386 void __init
free_bootmem(unsigned long addr
, unsigned long size
)
388 unsigned long start
, end
;
390 kmemleak_free_part(__va(addr
), size
);
392 start
= PFN_UP(addr
);
393 end
= PFN_DOWN(addr
+ size
);
395 mark_bootmem(start
, end
, 0, 0);
399 * reserve_bootmem_node - mark a page range as reserved
400 * @pgdat: node the range resides on
401 * @physaddr: starting address of the range
402 * @size: size of the range in bytes
403 * @flags: reservation flags (see linux/bootmem.h)
405 * Partial pages will be reserved.
407 * The range must reside completely on the specified node.
409 int __init
reserve_bootmem_node(pg_data_t
*pgdat
, unsigned long physaddr
,
410 unsigned long size
, int flags
)
412 unsigned long start
, end
;
414 start
= PFN_DOWN(physaddr
);
415 end
= PFN_UP(physaddr
+ size
);
417 return mark_bootmem_node(pgdat
->bdata
, start
, end
, 1, flags
);
421 * reserve_bootmem - mark a page range as usable
422 * @addr: starting address of the range
423 * @size: size of the range in bytes
424 * @flags: reservation flags (see linux/bootmem.h)
426 * Partial pages will be reserved.
428 * The range must be contiguous but may span node boundaries.
430 int __init
reserve_bootmem(unsigned long addr
, unsigned long size
,
433 unsigned long start
, end
;
435 start
= PFN_DOWN(addr
);
436 end
= PFN_UP(addr
+ size
);
438 return mark_bootmem(start
, end
, 1, flags
);
441 int __weak __init
reserve_bootmem_generic(unsigned long phys
, unsigned long len
,
444 return reserve_bootmem(phys
, len
, flags
);
447 static unsigned long __init
align_idx(struct bootmem_data
*bdata
,
448 unsigned long idx
, unsigned long step
)
450 unsigned long base
= bdata
->node_min_pfn
;
453 * Align the index with respect to the node start so that the
454 * combination of both satisfies the requested alignment.
457 return ALIGN(base
+ idx
, step
) - base
;
460 static unsigned long __init
align_off(struct bootmem_data
*bdata
,
461 unsigned long off
, unsigned long align
)
463 unsigned long base
= PFN_PHYS(bdata
->node_min_pfn
);
465 /* Same as align_idx for byte offsets */
467 return ALIGN(base
+ off
, align
) - base
;
470 static void * __init
alloc_bootmem_core(struct bootmem_data
*bdata
,
471 unsigned long size
, unsigned long align
,
472 unsigned long goal
, unsigned long limit
)
474 unsigned long fallback
= 0;
475 unsigned long min
, max
, start
, sidx
, midx
, step
;
477 bdebug("nid=%td size=%lx [%lu pages] align=%lx goal=%lx limit=%lx\n",
478 bdata
- bootmem_node_data
, size
, PAGE_ALIGN(size
) >> PAGE_SHIFT
,
482 BUG_ON(align
& (align
- 1));
483 BUG_ON(limit
&& goal
+ size
> limit
);
485 if (!bdata
->node_bootmem_map
)
488 min
= bdata
->node_min_pfn
;
489 max
= bdata
->node_low_pfn
;
492 limit
>>= PAGE_SHIFT
;
494 if (limit
&& max
> limit
)
499 step
= max(align
>> PAGE_SHIFT
, 1UL);
501 if (goal
&& min
< goal
&& goal
< max
)
502 start
= ALIGN(goal
, step
);
504 start
= ALIGN(min
, step
);
506 sidx
= start
- bdata
->node_min_pfn
;
507 midx
= max
- bdata
->node_min_pfn
;
509 if (bdata
->hint_idx
> sidx
) {
511 * Handle the valid case of sidx being zero and still
512 * catch the fallback below.
515 sidx
= align_idx(bdata
, bdata
->hint_idx
, step
);
521 unsigned long eidx
, i
, start_off
, end_off
;
523 sidx
= find_next_zero_bit(bdata
->node_bootmem_map
, midx
, sidx
);
524 sidx
= align_idx(bdata
, sidx
, step
);
525 eidx
= sidx
+ PFN_UP(size
);
527 if (sidx
>= midx
|| eidx
> midx
)
530 for (i
= sidx
; i
< eidx
; i
++)
531 if (test_bit(i
, bdata
->node_bootmem_map
)) {
532 sidx
= align_idx(bdata
, i
, step
);
538 if (bdata
->last_end_off
& (PAGE_SIZE
- 1) &&
539 PFN_DOWN(bdata
->last_end_off
) + 1 == sidx
)
540 start_off
= align_off(bdata
, bdata
->last_end_off
, align
);
542 start_off
= PFN_PHYS(sidx
);
544 merge
= PFN_DOWN(start_off
) < sidx
;
545 end_off
= start_off
+ size
;
547 bdata
->last_end_off
= end_off
;
548 bdata
->hint_idx
= PFN_UP(end_off
);
551 * Reserve the area now:
553 if (__reserve(bdata
, PFN_DOWN(start_off
) + merge
,
554 PFN_UP(end_off
), BOOTMEM_EXCLUSIVE
))
557 region
= phys_to_virt(PFN_PHYS(bdata
->node_min_pfn
) +
559 memset(region
, 0, size
);
561 * The min_count is set to 0 so that bootmem allocated blocks
562 * are never reported as leaks.
564 kmemleak_alloc(region
, size
, 0, 0);
569 sidx
= align_idx(bdata
, fallback
- 1, step
);
577 static void * __init
alloc_arch_preferred_bootmem(bootmem_data_t
*bdata
,
578 unsigned long size
, unsigned long align
,
579 unsigned long goal
, unsigned long limit
)
581 if (WARN_ON_ONCE(slab_is_available()))
582 return kzalloc(size
, GFP_NOWAIT
);
584 #ifdef CONFIG_HAVE_ARCH_BOOTMEM
586 bootmem_data_t
*p_bdata
;
588 p_bdata
= bootmem_arch_preferred_node(bdata
, size
, align
,
591 return alloc_bootmem_core(p_bdata
, size
, align
,
598 static void * __init
___alloc_bootmem_nopanic(unsigned long size
,
603 bootmem_data_t
*bdata
;
607 region
= alloc_arch_preferred_bootmem(NULL
, size
, align
, goal
, limit
);
611 list_for_each_entry(bdata
, &bdata_list
, list
) {
612 if (goal
&& bdata
->node_low_pfn
<= PFN_DOWN(goal
))
614 if (limit
&& bdata
->node_min_pfn
>= PFN_DOWN(limit
))
617 region
= alloc_bootmem_core(bdata
, size
, align
, goal
, limit
);
631 * __alloc_bootmem_nopanic - allocate boot memory without panicking
632 * @size: size of the request in bytes
633 * @align: alignment of the region
634 * @goal: preferred starting address of the region
636 * The goal is dropped if it can not be satisfied and the allocation will
637 * fall back to memory below @goal.
639 * Allocation may happen on any node in the system.
641 * Returns NULL on failure.
643 void * __init
__alloc_bootmem_nopanic(unsigned long size
, unsigned long align
,
646 unsigned long limit
= 0;
648 return ___alloc_bootmem_nopanic(size
, align
, goal
, limit
);
651 static void * __init
___alloc_bootmem(unsigned long size
, unsigned long align
,
652 unsigned long goal
, unsigned long limit
)
654 void *mem
= ___alloc_bootmem_nopanic(size
, align
, goal
, limit
);
659 * Whoops, we cannot satisfy the allocation request.
661 printk(KERN_ALERT
"bootmem alloc of %lu bytes failed!\n", size
);
662 panic("Out of memory");
667 * __alloc_bootmem - allocate boot memory
668 * @size: size of the request in bytes
669 * @align: alignment of the region
670 * @goal: preferred starting address of the region
672 * The goal is dropped if it can not be satisfied and the allocation will
673 * fall back to memory below @goal.
675 * Allocation may happen on any node in the system.
677 * The function panics if the request can not be satisfied.
679 void * __init
__alloc_bootmem(unsigned long size
, unsigned long align
,
682 unsigned long limit
= 0;
684 return ___alloc_bootmem(size
, align
, goal
, limit
);
687 static void * __init
___alloc_bootmem_node(bootmem_data_t
*bdata
,
688 unsigned long size
, unsigned long align
,
689 unsigned long goal
, unsigned long limit
)
693 ptr
= alloc_arch_preferred_bootmem(bdata
, size
, align
, goal
, limit
);
697 ptr
= alloc_bootmem_core(bdata
, size
, align
, goal
, limit
);
701 return ___alloc_bootmem(size
, align
, goal
, limit
);
705 * __alloc_bootmem_node - allocate boot memory from a specific node
706 * @pgdat: node to allocate from
707 * @size: size of the request in bytes
708 * @align: alignment of the region
709 * @goal: preferred starting address of the region
711 * The goal is dropped if it can not be satisfied and the allocation will
712 * fall back to memory below @goal.
714 * Allocation may fall back to any node in the system if the specified node
715 * can not hold the requested memory.
717 * The function panics if the request can not be satisfied.
719 void * __init
__alloc_bootmem_node(pg_data_t
*pgdat
, unsigned long size
,
720 unsigned long align
, unsigned long goal
)
722 if (WARN_ON_ONCE(slab_is_available()))
723 return kzalloc_node(size
, GFP_NOWAIT
, pgdat
->node_id
);
725 return ___alloc_bootmem_node(pgdat
->bdata
, size
, align
, goal
, 0);
728 void * __init
__alloc_bootmem_node_high(pg_data_t
*pgdat
, unsigned long size
,
729 unsigned long align
, unsigned long goal
)
732 unsigned long end_pfn
;
734 if (WARN_ON_ONCE(slab_is_available()))
735 return kzalloc_node(size
, GFP_NOWAIT
, pgdat
->node_id
);
737 /* update goal according ...MAX_DMA32_PFN */
738 end_pfn
= pgdat
->node_start_pfn
+ pgdat
->node_spanned_pages
;
740 if (end_pfn
> MAX_DMA32_PFN
+ (128 >> (20 - PAGE_SHIFT
)) &&
741 (goal
>> PAGE_SHIFT
) < MAX_DMA32_PFN
) {
743 unsigned long new_goal
;
745 new_goal
= MAX_DMA32_PFN
<< PAGE_SHIFT
;
746 ptr
= alloc_bootmem_core(pgdat
->bdata
, size
, align
,
753 return __alloc_bootmem_node(pgdat
, size
, align
, goal
);
757 #ifdef CONFIG_SPARSEMEM
759 * alloc_bootmem_section - allocate boot memory from a specific section
760 * @size: size of the request in bytes
761 * @section_nr: sparse map section to allocate from
763 * Return NULL on failure.
765 void * __init
alloc_bootmem_section(unsigned long size
,
766 unsigned long section_nr
)
768 bootmem_data_t
*bdata
;
769 unsigned long pfn
, goal
, limit
;
771 pfn
= section_nr_to_pfn(section_nr
);
772 goal
= pfn
<< PAGE_SHIFT
;
773 limit
= section_nr_to_pfn(section_nr
+ 1) << PAGE_SHIFT
;
774 bdata
= &bootmem_node_data
[early_pfn_to_nid(pfn
)];
776 if (goal
+ size
> limit
)
779 return alloc_bootmem_core(bdata
, size
, SMP_CACHE_BYTES
, goal
, limit
);
783 void * __init
__alloc_bootmem_node_nopanic(pg_data_t
*pgdat
, unsigned long size
,
784 unsigned long align
, unsigned long goal
)
788 if (WARN_ON_ONCE(slab_is_available()))
789 return kzalloc_node(size
, GFP_NOWAIT
, pgdat
->node_id
);
791 ptr
= alloc_arch_preferred_bootmem(pgdat
->bdata
, size
, align
, goal
, 0);
795 ptr
= alloc_bootmem_core(pgdat
->bdata
, size
, align
, goal
, 0);
799 return __alloc_bootmem_nopanic(size
, align
, goal
);
802 #ifndef ARCH_LOW_ADDRESS_LIMIT
803 #define ARCH_LOW_ADDRESS_LIMIT 0xffffffffUL
807 * __alloc_bootmem_low - allocate low boot memory
808 * @size: size of the request in bytes
809 * @align: alignment of the region
810 * @goal: preferred starting address of the region
812 * The goal is dropped if it can not be satisfied and the allocation will
813 * fall back to memory below @goal.
815 * Allocation may happen on any node in the system.
817 * The function panics if the request can not be satisfied.
819 void * __init
__alloc_bootmem_low(unsigned long size
, unsigned long align
,
822 return ___alloc_bootmem(size
, align
, goal
, ARCH_LOW_ADDRESS_LIMIT
);
826 * __alloc_bootmem_low_node - allocate low boot memory from a specific node
827 * @pgdat: node to allocate from
828 * @size: size of the request in bytes
829 * @align: alignment of the region
830 * @goal: preferred starting address of the region
832 * The goal is dropped if it can not be satisfied and the allocation will
833 * fall back to memory below @goal.
835 * Allocation may fall back to any node in the system if the specified node
836 * can not hold the requested memory.
838 * The function panics if the request can not be satisfied.
840 void * __init
__alloc_bootmem_low_node(pg_data_t
*pgdat
, unsigned long size
,
841 unsigned long align
, unsigned long goal
)
843 if (WARN_ON_ONCE(slab_is_available()))
844 return kzalloc_node(size
, GFP_NOWAIT
, pgdat
->node_id
);
846 return ___alloc_bootmem_node(pgdat
->bdata
, size
, align
,
847 goal
, ARCH_LOW_ADDRESS_LIMIT
);