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/bootmem.h>
14 #include <linux/module.h>
18 #include <asm/processor.h>
22 unsigned long max_low_pfn
;
23 unsigned long min_low_pfn
;
24 unsigned long max_pfn
;
26 #ifdef CONFIG_CRASH_DUMP
28 * If we have booted due to a crash, max_pfn will be a very low value. We need
29 * to know the amount of memory that the previous kernel used.
31 unsigned long saved_max_pfn
;
34 bootmem_data_t bootmem_node_data
[MAX_NUMNODES
] __initdata
;
36 static struct list_head bdata_list __initdata
= LIST_HEAD_INIT(bdata_list
);
38 static int bootmem_debug
;
40 static int __init
bootmem_debug_setup(char *buf
)
45 early_param("bootmem_debug", bootmem_debug_setup
);
47 #define bdebug(fmt, args...) ({ \
48 if (unlikely(bootmem_debug)) \
51 __FUNCTION__, ## args); \
54 static unsigned long __init
bootmap_bytes(unsigned long pages
)
56 unsigned long bytes
= (pages
+ 7) / 8;
58 return ALIGN(bytes
, sizeof(long));
62 * bootmem_bootmap_pages - calculate bitmap size in pages
63 * @pages: number of pages the bitmap has to represent
65 unsigned long __init
bootmem_bootmap_pages(unsigned long pages
)
67 unsigned long bytes
= bootmap_bytes(pages
);
69 return PAGE_ALIGN(bytes
) >> PAGE_SHIFT
;
75 static void __init
link_bootmem(bootmem_data_t
*bdata
)
77 struct list_head
*iter
;
79 list_for_each(iter
, &bdata_list
) {
82 ent
= list_entry(iter
, bootmem_data_t
, list
);
83 if (bdata
->node_min_pfn
< ent
->node_min_pfn
)
86 list_add_tail(&bdata
->list
, iter
);
90 * Called once to set up the allocator itself.
92 static unsigned long __init
init_bootmem_core(bootmem_data_t
*bdata
,
93 unsigned long mapstart
, unsigned long start
, unsigned long end
)
95 unsigned long mapsize
;
97 mminit_validate_memmodel_limits(&start
, &end
);
98 bdata
->node_bootmem_map
= phys_to_virt(PFN_PHYS(mapstart
));
99 bdata
->node_min_pfn
= start
;
100 bdata
->node_low_pfn
= end
;
104 * Initially all pages are reserved - setup_arch() has to
105 * register free RAM areas explicitly.
107 mapsize
= bootmap_bytes(end
- start
);
108 memset(bdata
->node_bootmem_map
, 0xff, mapsize
);
110 bdebug("nid=%td start=%lx map=%lx end=%lx mapsize=%lx\n",
111 bdata
- bootmem_node_data
, start
, mapstart
, end
, mapsize
);
117 * init_bootmem_node - register a node as boot memory
118 * @pgdat: node to register
119 * @freepfn: pfn where the bitmap for this node is to be placed
120 * @startpfn: first pfn on the node
121 * @endpfn: first pfn after the node
123 * Returns the number of bytes needed to hold the bitmap for this node.
125 unsigned long __init
init_bootmem_node(pg_data_t
*pgdat
, unsigned long freepfn
,
126 unsigned long startpfn
, unsigned long endpfn
)
128 return init_bootmem_core(pgdat
->bdata
, freepfn
, startpfn
, endpfn
);
132 * init_bootmem - register boot memory
133 * @start: pfn where the bitmap is to be placed
134 * @pages: number of available physical pages
136 * Returns the number of bytes needed to hold the bitmap.
138 unsigned long __init
init_bootmem(unsigned long start
, unsigned long pages
)
142 return init_bootmem_core(NODE_DATA(0)->bdata
, start
, 0, pages
);
145 static unsigned long __init
free_all_bootmem_core(bootmem_data_t
*bdata
)
149 unsigned long start
, end
, pages
, count
= 0;
151 if (!bdata
->node_bootmem_map
)
154 start
= bdata
->node_min_pfn
;
155 end
= bdata
->node_low_pfn
;
158 * If the start is aligned to the machines wordsize, we might
159 * be able to free pages in bulks of that order.
161 aligned
= !(start
& (BITS_PER_LONG
- 1));
163 bdebug("nid=%td start=%lx end=%lx aligned=%d\n",
164 bdata
- bootmem_node_data
, start
, end
, aligned
);
166 while (start
< end
) {
167 unsigned long *map
, idx
, vec
;
169 map
= bdata
->node_bootmem_map
;
170 idx
= start
- bdata
->node_min_pfn
;
171 vec
= ~map
[idx
/ BITS_PER_LONG
];
173 if (aligned
&& vec
== ~0UL && start
+ BITS_PER_LONG
< end
) {
174 int order
= ilog2(BITS_PER_LONG
);
176 __free_pages_bootmem(pfn_to_page(start
), order
);
177 count
+= BITS_PER_LONG
;
179 unsigned long off
= 0;
181 while (vec
&& off
< BITS_PER_LONG
) {
183 page
= pfn_to_page(start
+ off
);
184 __free_pages_bootmem(page
, 0);
191 start
+= BITS_PER_LONG
;
194 page
= virt_to_page(bdata
->node_bootmem_map
);
195 pages
= bdata
->node_low_pfn
- bdata
->node_min_pfn
;
196 pages
= bootmem_bootmap_pages(pages
);
199 __free_pages_bootmem(page
++, 0);
201 bdebug("nid=%td released=%lx\n", bdata
- bootmem_node_data
, count
);
207 * free_all_bootmem_node - release a node's free pages to the buddy allocator
208 * @pgdat: node to be released
210 * Returns the number of pages actually released.
212 unsigned long __init
free_all_bootmem_node(pg_data_t
*pgdat
)
214 register_page_bootmem_info_node(pgdat
);
215 return free_all_bootmem_core(pgdat
->bdata
);
219 * free_all_bootmem - release free pages to the buddy allocator
221 * Returns the number of pages actually released.
223 unsigned long __init
free_all_bootmem(void)
225 return free_all_bootmem_core(NODE_DATA(0)->bdata
);
228 static void __init
__free(bootmem_data_t
*bdata
,
229 unsigned long sidx
, unsigned long eidx
)
233 bdebug("nid=%td start=%lx end=%lx\n", bdata
- bootmem_node_data
,
234 sidx
+ bdata
->node_min_pfn
,
235 eidx
+ bdata
->node_min_pfn
);
237 if (bdata
->hint_idx
> sidx
)
238 bdata
->hint_idx
= sidx
;
240 for (idx
= sidx
; idx
< eidx
; idx
++)
241 if (!test_and_clear_bit(idx
, bdata
->node_bootmem_map
))
245 static int __init
__reserve(bootmem_data_t
*bdata
, unsigned long sidx
,
246 unsigned long eidx
, int flags
)
249 int exclusive
= flags
& BOOTMEM_EXCLUSIVE
;
251 bdebug("nid=%td start=%lx end=%lx flags=%x\n",
252 bdata
- bootmem_node_data
,
253 sidx
+ bdata
->node_min_pfn
,
254 eidx
+ bdata
->node_min_pfn
,
257 for (idx
= sidx
; idx
< eidx
; idx
++)
258 if (test_and_set_bit(idx
, bdata
->node_bootmem_map
)) {
260 __free(bdata
, sidx
, idx
);
263 bdebug("silent double reserve of PFN %lx\n",
264 idx
+ bdata
->node_min_pfn
);
269 static int __init
mark_bootmem_node(bootmem_data_t
*bdata
,
270 unsigned long start
, unsigned long end
,
271 int reserve
, int flags
)
273 unsigned long sidx
, eidx
;
275 bdebug("nid=%td start=%lx end=%lx reserve=%d flags=%x\n",
276 bdata
- bootmem_node_data
, start
, end
, reserve
, flags
);
278 BUG_ON(start
< bdata
->node_min_pfn
);
279 BUG_ON(end
> bdata
->node_low_pfn
);
281 sidx
= start
- bdata
->node_min_pfn
;
282 eidx
= end
- bdata
->node_min_pfn
;
285 return __reserve(bdata
, sidx
, eidx
, flags
);
287 __free(bdata
, sidx
, eidx
);
291 static int __init
mark_bootmem(unsigned long start
, unsigned long end
,
292 int reserve
, int flags
)
295 bootmem_data_t
*bdata
;
298 list_for_each_entry(bdata
, &bdata_list
, list
) {
302 if (pos
< bdata
->node_min_pfn
||
303 pos
>= bdata
->node_low_pfn
) {
304 BUG_ON(pos
!= start
);
308 max
= min(bdata
->node_low_pfn
, end
);
310 err
= mark_bootmem_node(bdata
, pos
, max
, reserve
, flags
);
311 if (reserve
&& err
) {
312 mark_bootmem(start
, pos
, 0, 0);
318 pos
= bdata
->node_low_pfn
;
324 * free_bootmem_node - mark a page range as usable
325 * @pgdat: node the range resides on
326 * @physaddr: starting address of the range
327 * @size: size of the range in bytes
329 * Partial pages will be considered reserved and left as they are.
331 * The range must reside completely on the specified node.
333 void __init
free_bootmem_node(pg_data_t
*pgdat
, unsigned long physaddr
,
336 unsigned long start
, end
;
338 start
= PFN_UP(physaddr
);
339 end
= PFN_DOWN(physaddr
+ size
);
341 mark_bootmem_node(pgdat
->bdata
, start
, end
, 0, 0);
345 * free_bootmem - mark a page range as usable
346 * @addr: starting address of the range
347 * @size: size of the range in bytes
349 * Partial pages will be considered reserved and left as they are.
351 * The range must be contiguous but may span node boundaries.
353 void __init
free_bootmem(unsigned long addr
, unsigned long size
)
355 unsigned long start
, end
;
357 start
= PFN_UP(addr
);
358 end
= PFN_DOWN(addr
+ size
);
360 mark_bootmem(start
, end
, 0, 0);
364 * reserve_bootmem_node - mark a page range as reserved
365 * @pgdat: node the range resides on
366 * @physaddr: starting address of the range
367 * @size: size of the range in bytes
368 * @flags: reservation flags (see linux/bootmem.h)
370 * Partial pages will be reserved.
372 * The range must reside completely on the specified node.
374 int __init
reserve_bootmem_node(pg_data_t
*pgdat
, unsigned long physaddr
,
375 unsigned long size
, int flags
)
377 unsigned long start
, end
;
379 start
= PFN_DOWN(physaddr
);
380 end
= PFN_UP(physaddr
+ size
);
382 return mark_bootmem_node(pgdat
->bdata
, start
, end
, 1, flags
);
385 #ifndef CONFIG_HAVE_ARCH_BOOTMEM_NODE
387 * reserve_bootmem - mark a page range as usable
388 * @addr: starting address of the range
389 * @size: size of the range in bytes
390 * @flags: reservation flags (see linux/bootmem.h)
392 * Partial pages will be reserved.
394 * The range must be contiguous but may span node boundaries.
396 int __init
reserve_bootmem(unsigned long addr
, unsigned long size
,
399 unsigned long start
, end
;
401 start
= PFN_DOWN(addr
);
402 end
= PFN_UP(addr
+ size
);
404 return mark_bootmem(start
, end
, 1, flags
);
406 #endif /* !CONFIG_HAVE_ARCH_BOOTMEM_NODE */
408 static void * __init
alloc_bootmem_core(struct bootmem_data
*bdata
,
409 unsigned long size
, unsigned long align
,
410 unsigned long goal
, unsigned long limit
)
412 unsigned long fallback
= 0;
413 unsigned long min
, max
, start
, sidx
, midx
, step
;
416 BUG_ON(align
& (align
- 1));
417 BUG_ON(limit
&& goal
+ size
> limit
);
419 if (!bdata
->node_bootmem_map
)
422 bdebug("nid=%td size=%lx [%lu pages] align=%lx goal=%lx limit=%lx\n",
423 bdata
- bootmem_node_data
, size
, PAGE_ALIGN(size
) >> PAGE_SHIFT
,
426 min
= bdata
->node_min_pfn
;
427 max
= bdata
->node_low_pfn
;
430 limit
>>= PAGE_SHIFT
;
432 if (limit
&& max
> limit
)
437 step
= max(align
>> PAGE_SHIFT
, 1UL);
439 if (goal
&& min
< goal
&& goal
< max
)
440 start
= ALIGN(goal
, step
);
442 start
= ALIGN(min
, step
);
444 sidx
= start
- bdata
->node_min_pfn
;;
445 midx
= max
- bdata
->node_min_pfn
;
447 if (bdata
->hint_idx
> sidx
) {
449 * Handle the valid case of sidx being zero and still
450 * catch the fallback below.
453 sidx
= ALIGN(bdata
->hint_idx
, step
);
459 unsigned long eidx
, i
, start_off
, end_off
;
461 sidx
= find_next_zero_bit(bdata
->node_bootmem_map
, midx
, sidx
);
462 sidx
= ALIGN(sidx
, step
);
463 eidx
= sidx
+ PFN_UP(size
);
465 if (sidx
>= midx
|| eidx
> midx
)
468 for (i
= sidx
; i
< eidx
; i
++)
469 if (test_bit(i
, bdata
->node_bootmem_map
)) {
470 sidx
= ALIGN(i
, step
);
476 if (bdata
->last_end_off
&&
477 PFN_DOWN(bdata
->last_end_off
) + 1 == sidx
)
478 start_off
= ALIGN(bdata
->last_end_off
, align
);
480 start_off
= PFN_PHYS(sidx
);
482 merge
= PFN_DOWN(start_off
) < sidx
;
483 end_off
= start_off
+ size
;
485 bdata
->last_end_off
= end_off
;
486 bdata
->hint_idx
= PFN_UP(end_off
);
489 * Reserve the area now:
491 if (__reserve(bdata
, PFN_DOWN(start_off
) + merge
,
492 PFN_UP(end_off
), BOOTMEM_EXCLUSIVE
))
495 region
= phys_to_virt(PFN_PHYS(bdata
->node_min_pfn
) +
497 memset(region
, 0, size
);
502 sidx
= ALIGN(fallback
- 1, step
);
510 static void * __init
___alloc_bootmem_nopanic(unsigned long size
,
515 bootmem_data_t
*bdata
;
518 list_for_each_entry(bdata
, &bdata_list
, list
) {
521 if (goal
&& bdata
->node_low_pfn
<= PFN_DOWN(goal
))
523 if (limit
&& bdata
->node_min_pfn
>= PFN_DOWN(limit
))
526 region
= alloc_bootmem_core(bdata
, size
, align
, goal
, limit
);
540 * __alloc_bootmem_nopanic - allocate boot memory without panicking
541 * @size: size of the request in bytes
542 * @align: alignment of the region
543 * @goal: preferred starting address of the region
545 * The goal is dropped if it can not be satisfied and the allocation will
546 * fall back to memory below @goal.
548 * Allocation may happen on any node in the system.
550 * Returns NULL on failure.
552 void * __init
__alloc_bootmem_nopanic(unsigned long size
, unsigned long align
,
555 return ___alloc_bootmem_nopanic(size
, align
, goal
, 0);
558 static void * __init
___alloc_bootmem(unsigned long size
, unsigned long align
,
559 unsigned long goal
, unsigned long limit
)
561 void *mem
= ___alloc_bootmem_nopanic(size
, align
, goal
, limit
);
566 * Whoops, we cannot satisfy the allocation request.
568 printk(KERN_ALERT
"bootmem alloc of %lu bytes failed!\n", size
);
569 panic("Out of memory");
574 * __alloc_bootmem - allocate boot memory
575 * @size: size of the request in bytes
576 * @align: alignment of the region
577 * @goal: preferred starting address of the region
579 * The goal is dropped if it can not be satisfied and the allocation will
580 * fall back to memory below @goal.
582 * Allocation may happen on any node in the system.
584 * The function panics if the request can not be satisfied.
586 void * __init
__alloc_bootmem(unsigned long size
, unsigned long align
,
589 return ___alloc_bootmem(size
, align
, goal
, 0);
592 static void * __init
___alloc_bootmem_node(bootmem_data_t
*bdata
,
593 unsigned long size
, unsigned long align
,
594 unsigned long goal
, unsigned long limit
)
598 ptr
= alloc_bootmem_core(bdata
, size
, align
, goal
, limit
);
602 return ___alloc_bootmem(size
, align
, goal
, limit
);
606 * __alloc_bootmem_node - allocate boot memory from a specific node
607 * @pgdat: node to allocate from
608 * @size: size of the request in bytes
609 * @align: alignment of the region
610 * @goal: preferred starting address of the region
612 * The goal is dropped if it can not be satisfied and the allocation will
613 * fall back to memory below @goal.
615 * Allocation may fall back to any node in the system if the specified node
616 * can not hold the requested memory.
618 * The function panics if the request can not be satisfied.
620 void * __init
__alloc_bootmem_node(pg_data_t
*pgdat
, unsigned long size
,
621 unsigned long align
, unsigned long goal
)
623 return ___alloc_bootmem_node(pgdat
->bdata
, size
, align
, goal
, 0);
626 #ifdef CONFIG_SPARSEMEM
628 * alloc_bootmem_section - allocate boot memory from a specific section
629 * @size: size of the request in bytes
630 * @section_nr: sparse map section to allocate from
632 * Return NULL on failure.
634 void * __init
alloc_bootmem_section(unsigned long size
,
635 unsigned long section_nr
)
637 bootmem_data_t
*bdata
;
638 unsigned long pfn
, goal
, limit
;
640 pfn
= section_nr_to_pfn(section_nr
);
641 goal
= pfn
<< PAGE_SHIFT
;
642 limit
= section_nr_to_pfn(section_nr
+ 1) << PAGE_SHIFT
;
643 bdata
= &bootmem_node_data
[early_pfn_to_nid(pfn
)];
645 return alloc_bootmem_core(bdata
, size
, SMP_CACHE_BYTES
, goal
, limit
);
649 void * __init
__alloc_bootmem_node_nopanic(pg_data_t
*pgdat
, unsigned long size
,
650 unsigned long align
, unsigned long goal
)
654 ptr
= alloc_bootmem_core(pgdat
->bdata
, size
, align
, goal
, 0);
658 return __alloc_bootmem_nopanic(size
, align
, goal
);
661 #ifndef ARCH_LOW_ADDRESS_LIMIT
662 #define ARCH_LOW_ADDRESS_LIMIT 0xffffffffUL
666 * __alloc_bootmem_low - allocate low boot memory
667 * @size: size of the request in bytes
668 * @align: alignment of the region
669 * @goal: preferred starting address of the region
671 * The goal is dropped if it can not be satisfied and the allocation will
672 * fall back to memory below @goal.
674 * Allocation may happen on any node in the system.
676 * The function panics if the request can not be satisfied.
678 void * __init
__alloc_bootmem_low(unsigned long size
, unsigned long align
,
681 return ___alloc_bootmem(size
, align
, goal
, ARCH_LOW_ADDRESS_LIMIT
);
685 * __alloc_bootmem_low_node - allocate low boot memory from a specific node
686 * @pgdat: node to allocate from
687 * @size: size of the request in bytes
688 * @align: alignment of the region
689 * @goal: preferred starting address of the region
691 * The goal is dropped if it can not be satisfied and the allocation will
692 * fall back to memory below @goal.
694 * Allocation may fall back to any node in the system if the specified node
695 * can not hold the requested memory.
697 * The function panics if the request can not be satisfied.
699 void * __init
__alloc_bootmem_low_node(pg_data_t
*pgdat
, unsigned long size
,
700 unsigned long align
, unsigned long goal
)
702 return ___alloc_bootmem_node(pgdat
->bdata
, size
, align
,
703 goal
, ARCH_LOW_ADDRESS_LIMIT
);