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>
19 #include <linux/bug.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)
82 list_for_each_entry(ent, &bdata_list, list) {
83 if (bdata->node_min_pfn < ent->node_min_pfn) {
84 list_add_tail(&bdata->list, &ent->list);
89 list_add_tail(&bdata->list, &bdata_list);
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 physical 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 physaddr, unsigned long size)
159 unsigned long cursor, end;
161 kmemleak_free_part(__va(physaddr), size);
163 cursor = PFN_UP(physaddr);
164 end = PFN_DOWN(physaddr + 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 *map, start, end, pages, count = 0;
177 if (!bdata->node_bootmem_map)
180 map = bdata->node_bootmem_map;
181 start = bdata->node_min_pfn;
182 end = bdata->node_low_pfn;
184 bdebug("nid=%td start=%lx end=%lx\n",
185 bdata - bootmem_node_data, start, end);
187 while (start < end) {
188 unsigned long idx, vec;
191 idx = start - bdata->node_min_pfn;
192 shift = idx & (BITS_PER_LONG - 1);
194 * vec holds at most BITS_PER_LONG map bits,
195 * bit 0 corresponds to start.
197 vec = ~map[idx / BITS_PER_LONG];
201 if (end - start >= BITS_PER_LONG)
202 vec |= ~map[idx / BITS_PER_LONG + 1] <<
203 (BITS_PER_LONG - shift);
206 * If we have a properly aligned and fully unreserved
207 * BITS_PER_LONG block of pages in front of us, free
210 if (IS_ALIGNED(start, BITS_PER_LONG) && vec == ~0UL) {
211 int order = ilog2(BITS_PER_LONG);
213 __free_pages_bootmem(pfn_to_page(start), order);
214 count += BITS_PER_LONG;
215 start += BITS_PER_LONG;
217 unsigned long cur = start;
219 start = ALIGN(start + 1, BITS_PER_LONG);
220 while (vec && cur != start) {
222 page = pfn_to_page(cur);
223 __free_pages_bootmem(page, 0);
232 page = virt_to_page(bdata->node_bootmem_map);
233 pages = bdata->node_low_pfn - bdata->node_min_pfn;
234 pages = bootmem_bootmap_pages(pages);
237 __free_pages_bootmem(page++, 0);
239 bdebug("nid=%td released=%lx\n", bdata - bootmem_node_data, count);
244 static int reset_managed_pages_done __initdata;
246 void reset_node_managed_pages(pg_data_t *pgdat)
250 for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
251 z->managed_pages = 0;
254 void __init reset_all_zones_managed_pages(void)
256 struct pglist_data *pgdat;
258 if (reset_managed_pages_done)
261 for_each_online_pgdat(pgdat)
262 reset_node_managed_pages(pgdat);
264 reset_managed_pages_done = 1;
268 * free_all_bootmem - release free pages to the buddy allocator
270 * Returns the number of pages actually released.
272 unsigned long __init free_all_bootmem(void)
274 unsigned long total_pages = 0;
275 bootmem_data_t *bdata;
277 reset_all_zones_managed_pages();
279 list_for_each_entry(bdata, &bdata_list, list)
280 total_pages += free_all_bootmem_core(bdata);
282 totalram_pages += total_pages;
287 static void __init __free(bootmem_data_t *bdata,
288 unsigned long sidx, unsigned long eidx)
292 bdebug("nid=%td start=%lx end=%lx\n", bdata - bootmem_node_data,
293 sidx + bdata->node_min_pfn,
294 eidx + bdata->node_min_pfn);
296 if (bdata->hint_idx > sidx)
297 bdata->hint_idx = sidx;
299 for (idx = sidx; idx < eidx; idx++)
300 if (!test_and_clear_bit(idx, bdata->node_bootmem_map))
304 static int __init __reserve(bootmem_data_t *bdata, unsigned long sidx,
305 unsigned long eidx, int flags)
308 int exclusive = flags & BOOTMEM_EXCLUSIVE;
310 bdebug("nid=%td start=%lx end=%lx flags=%x\n",
311 bdata - bootmem_node_data,
312 sidx + bdata->node_min_pfn,
313 eidx + bdata->node_min_pfn,
316 for (idx = sidx; idx < eidx; idx++)
317 if (test_and_set_bit(idx, bdata->node_bootmem_map)) {
319 __free(bdata, sidx, idx);
322 bdebug("silent double reserve of PFN %lx\n",
323 idx + bdata->node_min_pfn);
328 static int __init mark_bootmem_node(bootmem_data_t *bdata,
329 unsigned long start, unsigned long end,
330 int reserve, int flags)
332 unsigned long sidx, eidx;
334 bdebug("nid=%td start=%lx end=%lx reserve=%d flags=%x\n",
335 bdata - bootmem_node_data, start, end, reserve, flags);
337 BUG_ON(start < bdata->node_min_pfn);
338 BUG_ON(end > bdata->node_low_pfn);
340 sidx = start - bdata->node_min_pfn;
341 eidx = end - bdata->node_min_pfn;
344 return __reserve(bdata, sidx, eidx, flags);
346 __free(bdata, sidx, eidx);
350 static int __init mark_bootmem(unsigned long start, unsigned long end,
351 int reserve, int flags)
354 bootmem_data_t *bdata;
357 list_for_each_entry(bdata, &bdata_list, list) {
361 if (pos < bdata->node_min_pfn ||
362 pos >= bdata->node_low_pfn) {
363 BUG_ON(pos != start);
367 max = min(bdata->node_low_pfn, end);
369 err = mark_bootmem_node(bdata, pos, max, reserve, flags);
370 if (reserve && err) {
371 mark_bootmem(start, pos, 0, 0);
377 pos = bdata->node_low_pfn;
383 * free_bootmem_node - mark a page range as usable
384 * @pgdat: node the range resides on
385 * @physaddr: starting address of the range
386 * @size: size of the range in bytes
388 * Partial pages will be considered reserved and left as they are.
390 * The range must reside completely on the specified node.
392 void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
395 unsigned long start, end;
397 kmemleak_free_part(__va(physaddr), size);
399 start = PFN_UP(physaddr);
400 end = PFN_DOWN(physaddr + size);
402 mark_bootmem_node(pgdat->bdata, start, end, 0, 0);
406 * free_bootmem - mark a page range as usable
407 * @addr: starting physical address of the range
408 * @size: size of the range in bytes
410 * Partial pages will be considered reserved and left as they are.
412 * The range must be contiguous but may span node boundaries.
414 void __init free_bootmem(unsigned long physaddr, unsigned long size)
416 unsigned long start, end;
418 kmemleak_free_part(__va(physaddr), size);
420 start = PFN_UP(physaddr);
421 end = PFN_DOWN(physaddr + size);
423 mark_bootmem(start, end, 0, 0);
427 * reserve_bootmem_node - mark a page range as reserved
428 * @pgdat: node the range resides on
429 * @physaddr: starting address of the range
430 * @size: size of the range in bytes
431 * @flags: reservation flags (see linux/bootmem.h)
433 * Partial pages will be reserved.
435 * The range must reside completely on the specified node.
437 int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
438 unsigned long size, int flags)
440 unsigned long start, end;
442 start = PFN_DOWN(physaddr);
443 end = PFN_UP(physaddr + size);
445 return mark_bootmem_node(pgdat->bdata, start, end, 1, flags);
449 * reserve_bootmem - mark a page range as reserved
450 * @addr: starting address of the range
451 * @size: size of the range in bytes
452 * @flags: reservation flags (see linux/bootmem.h)
454 * Partial pages will be reserved.
456 * The range must be contiguous but may span node boundaries.
458 int __init reserve_bootmem(unsigned long addr, unsigned long size,
461 unsigned long start, end;
463 start = PFN_DOWN(addr);
464 end = PFN_UP(addr + size);
466 return mark_bootmem(start, end, 1, flags);
469 static unsigned long __init align_idx(struct bootmem_data *bdata,
470 unsigned long idx, unsigned long step)
472 unsigned long base = bdata->node_min_pfn;
475 * Align the index with respect to the node start so that the
476 * combination of both satisfies the requested alignment.
479 return ALIGN(base + idx, step) - base;
482 static unsigned long __init align_off(struct bootmem_data *bdata,
483 unsigned long off, unsigned long align)
485 unsigned long base = PFN_PHYS(bdata->node_min_pfn);
487 /* Same as align_idx for byte offsets */
489 return ALIGN(base + off, align) - base;
492 static void * __init alloc_bootmem_bdata(struct bootmem_data *bdata,
493 unsigned long size, unsigned long align,
494 unsigned long goal, unsigned long limit)
496 unsigned long fallback = 0;
497 unsigned long min, max, start, sidx, midx, step;
499 bdebug("nid=%td size=%lx [%lu pages] align=%lx goal=%lx limit=%lx\n",
500 bdata - bootmem_node_data, size, PAGE_ALIGN(size) >> PAGE_SHIFT,
504 BUG_ON(align & (align - 1));
505 BUG_ON(limit && goal + size > limit);
507 if (!bdata->node_bootmem_map)
510 min = bdata->node_min_pfn;
511 max = bdata->node_low_pfn;
514 limit >>= PAGE_SHIFT;
516 if (limit && max > limit)
521 step = max(align >> PAGE_SHIFT, 1UL);
523 if (goal && min < goal && goal < max)
524 start = ALIGN(goal, step);
526 start = ALIGN(min, step);
528 sidx = start - bdata->node_min_pfn;
529 midx = max - bdata->node_min_pfn;
531 if (bdata->hint_idx > sidx) {
533 * Handle the valid case of sidx being zero and still
534 * catch the fallback below.
537 sidx = align_idx(bdata, bdata->hint_idx, step);
543 unsigned long eidx, i, start_off, end_off;
545 sidx = find_next_zero_bit(bdata->node_bootmem_map, midx, sidx);
546 sidx = align_idx(bdata, sidx, step);
547 eidx = sidx + PFN_UP(size);
549 if (sidx >= midx || eidx > midx)
552 for (i = sidx; i < eidx; i++)
553 if (test_bit(i, bdata->node_bootmem_map)) {
554 sidx = align_idx(bdata, i, step);
560 if (bdata->last_end_off & (PAGE_SIZE - 1) &&
561 PFN_DOWN(bdata->last_end_off) + 1 == sidx)
562 start_off = align_off(bdata, bdata->last_end_off, align);
564 start_off = PFN_PHYS(sidx);
566 merge = PFN_DOWN(start_off) < sidx;
567 end_off = start_off + size;
569 bdata->last_end_off = end_off;
570 bdata->hint_idx = PFN_UP(end_off);
573 * Reserve the area now:
575 if (__reserve(bdata, PFN_DOWN(start_off) + merge,
576 PFN_UP(end_off), BOOTMEM_EXCLUSIVE))
579 region = phys_to_virt(PFN_PHYS(bdata->node_min_pfn) +
581 memset(region, 0, size);
583 * The min_count is set to 0 so that bootmem allocated blocks
584 * are never reported as leaks.
586 kmemleak_alloc(region, size, 0, 0);
591 sidx = align_idx(bdata, fallback - 1, step);
599 static void * __init alloc_bootmem_core(unsigned long size,
604 bootmem_data_t *bdata;
607 if (WARN_ON_ONCE(slab_is_available()))
608 return kzalloc(size, GFP_NOWAIT);
610 list_for_each_entry(bdata, &bdata_list, list) {
611 if (goal && bdata->node_low_pfn <= PFN_DOWN(goal))
613 if (limit && bdata->node_min_pfn >= PFN_DOWN(limit))
616 region = alloc_bootmem_bdata(bdata, size, align, goal, limit);
624 static void * __init ___alloc_bootmem_nopanic(unsigned long size,
632 ptr = alloc_bootmem_core(size, align, goal, limit);
644 * __alloc_bootmem_nopanic - allocate boot memory without panicking
645 * @size: size of the request in bytes
646 * @align: alignment of the region
647 * @goal: preferred starting address of the region
649 * The goal is dropped if it can not be satisfied and the allocation will
650 * fall back to memory below @goal.
652 * Allocation may happen on any node in the system.
654 * Returns NULL on failure.
656 void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align,
659 unsigned long limit = 0;
661 return ___alloc_bootmem_nopanic(size, align, goal, limit);
664 static void * __init ___alloc_bootmem(unsigned long size, unsigned long align,
665 unsigned long goal, unsigned long limit)
667 void *mem = ___alloc_bootmem_nopanic(size, align, goal, limit);
672 * Whoops, we cannot satisfy the allocation request.
674 printk(KERN_ALERT "bootmem alloc of %lu bytes failed!\n", size);
675 panic("Out of memory");
680 * __alloc_bootmem - allocate boot memory
681 * @size: size of the request in bytes
682 * @align: alignment of the region
683 * @goal: preferred starting address of the region
685 * The goal is dropped if it can not be satisfied and the allocation will
686 * fall back to memory below @goal.
688 * Allocation may happen on any node in the system.
690 * The function panics if the request can not be satisfied.
692 void * __init __alloc_bootmem(unsigned long size, unsigned long align,
695 unsigned long limit = 0;
697 return ___alloc_bootmem(size, align, goal, limit);
700 void * __init ___alloc_bootmem_node_nopanic(pg_data_t *pgdat,
701 unsigned long size, unsigned long align,
702 unsigned long goal, unsigned long limit)
706 if (WARN_ON_ONCE(slab_is_available()))
707 return kzalloc(size, GFP_NOWAIT);
710 /* do not panic in alloc_bootmem_bdata() */
711 if (limit && goal + size > limit)
714 ptr = alloc_bootmem_bdata(pgdat->bdata, size, align, goal, limit);
718 ptr = alloc_bootmem_core(size, align, goal, limit);
730 void * __init __alloc_bootmem_node_nopanic(pg_data_t *pgdat, unsigned long size,
731 unsigned long align, unsigned long goal)
733 if (WARN_ON_ONCE(slab_is_available()))
734 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
736 return ___alloc_bootmem_node_nopanic(pgdat, size, align, goal, 0);
739 void * __init ___alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
740 unsigned long align, unsigned long goal,
745 ptr = ___alloc_bootmem_node_nopanic(pgdat, size, align, goal, 0);
749 printk(KERN_ALERT "bootmem alloc of %lu bytes failed!\n", size);
750 panic("Out of memory");
755 * __alloc_bootmem_node - allocate boot memory from a specific node
756 * @pgdat: node to allocate from
757 * @size: size of the request in bytes
758 * @align: alignment of the region
759 * @goal: preferred starting address of the region
761 * The goal is dropped if it can not be satisfied and the allocation will
762 * fall back to memory below @goal.
764 * Allocation may fall back to any node in the system if the specified node
765 * can not hold the requested memory.
767 * The function panics if the request can not be satisfied.
769 void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
770 unsigned long align, unsigned long goal)
772 if (WARN_ON_ONCE(slab_is_available()))
773 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
775 return ___alloc_bootmem_node(pgdat, size, align, goal, 0);
778 void * __init __alloc_bootmem_node_high(pg_data_t *pgdat, unsigned long size,
779 unsigned long align, unsigned long goal)
782 unsigned long end_pfn;
784 if (WARN_ON_ONCE(slab_is_available()))
785 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
787 /* update goal according ...MAX_DMA32_PFN */
788 end_pfn = pgdat_end_pfn(pgdat);
790 if (end_pfn > MAX_DMA32_PFN + (128 >> (20 - PAGE_SHIFT)) &&
791 (goal >> PAGE_SHIFT) < MAX_DMA32_PFN) {
793 unsigned long new_goal;
795 new_goal = MAX_DMA32_PFN << PAGE_SHIFT;
796 ptr = alloc_bootmem_bdata(pgdat->bdata, size, align,
803 return __alloc_bootmem_node(pgdat, size, align, goal);
807 #ifndef ARCH_LOW_ADDRESS_LIMIT
808 #define ARCH_LOW_ADDRESS_LIMIT 0xffffffffUL
812 * __alloc_bootmem_low - allocate low boot memory
813 * @size: size of the request in bytes
814 * @align: alignment of the region
815 * @goal: preferred starting address of the region
817 * The goal is dropped if it can not be satisfied and the allocation will
818 * fall back to memory below @goal.
820 * Allocation may happen on any node in the system.
822 * The function panics if the request can not be satisfied.
824 void * __init __alloc_bootmem_low(unsigned long size, unsigned long align,
827 return ___alloc_bootmem(size, align, goal, ARCH_LOW_ADDRESS_LIMIT);
830 void * __init __alloc_bootmem_low_nopanic(unsigned long size,
834 return ___alloc_bootmem_nopanic(size, align, goal,
835 ARCH_LOW_ADDRESS_LIMIT);
839 * __alloc_bootmem_low_node - allocate low boot memory from a specific node
840 * @pgdat: node to allocate from
841 * @size: size of the request in bytes
842 * @align: alignment of the region
843 * @goal: preferred starting address of the region
845 * The goal is dropped if it can not be satisfied and the allocation will
846 * fall back to memory below @goal.
848 * Allocation may fall back to any node in the system if the specified node
849 * can not hold the requested memory.
851 * The function panics if the request can not be satisfied.
853 void * __init __alloc_bootmem_low_node(pg_data_t *pgdat, unsigned long size,
854 unsigned long align, unsigned long goal)
856 if (WARN_ON_ONCE(slab_is_available()))
857 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
859 return ___alloc_bootmem_node(pgdat, size, align,
860 goal, ARCH_LOW_ADDRESS_LIMIT);