rbd: do not allow remove of mounted-on image
[linux/fpc-iii.git] / mm / bootmem.c
blobaf3d5afb88f643b803f14497f2441f727dd0b07a
1 /*
2 * bootmem - A boot-time physical memory allocator and configurator
4 * Copyright (C) 1999 Ingo Molnar
5 * 1999 Kanoj Sarcar, SGI
6 * 2008 Johannes Weiner
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>
20 #include <asm/bug.h>
21 #include <asm/io.h>
22 #include <asm/processor.h>
24 #include "internal.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);
31 #endif
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)
45 bootmem_debug = 1;
46 return 0;
48 early_param("bootmem_debug", bootmem_debug_setup);
50 #define bdebug(fmt, args...) ({ \
51 if (unlikely(bootmem_debug)) \
52 printk(KERN_INFO \
53 "bootmem::%s " fmt, \
54 __func__, ## args); \
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));
64 /**
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;
76 * link bdata in order
78 static void __init link_bootmem(bootmem_data_t *bdata)
80 bootmem_data_t *ent;
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);
85 return;
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;
104 link_bootmem(bdata);
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);
116 return 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)
143 max_low_pfn = pages;
144 min_low_pfn = start;
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);
168 totalram_pages++;
172 static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)
174 struct page *page;
175 unsigned long start, end, pages, count = 0;
177 if (!bdata->node_bootmem_map)
178 return 0;
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;
188 unsigned shift;
190 map = bdata->node_bootmem_map;
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];
199 if (shift) {
200 vec >>= shift;
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
208 * it in one go.
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;
216 } else {
217 unsigned long cur = start;
219 start = ALIGN(start + 1, BITS_PER_LONG);
220 while (vec && cur != start) {
221 if (vec & 1) {
222 page = pfn_to_page(cur);
223 __free_pages_bootmem(page, 0);
224 count++;
226 vec >>= 1;
227 ++cur;
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);
235 count += pages;
236 while (pages--)
237 __free_pages_bootmem(page++, 0);
239 bdebug("nid=%td released=%lx\n", bdata - bootmem_node_data, count);
241 return count;
245 * free_all_bootmem_node - release a node's free pages to the buddy allocator
246 * @pgdat: node to be released
248 * Returns the number of pages actually released.
250 unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
252 register_page_bootmem_info_node(pgdat);
253 return free_all_bootmem_core(pgdat->bdata);
257 * free_all_bootmem - release free pages to the buddy allocator
259 * Returns the number of pages actually released.
261 unsigned long __init free_all_bootmem(void)
263 unsigned long total_pages = 0;
264 bootmem_data_t *bdata;
266 list_for_each_entry(bdata, &bdata_list, list)
267 total_pages += free_all_bootmem_core(bdata);
269 return total_pages;
272 static void __init __free(bootmem_data_t *bdata,
273 unsigned long sidx, unsigned long eidx)
275 unsigned long idx;
277 bdebug("nid=%td start=%lx end=%lx\n", bdata - bootmem_node_data,
278 sidx + bdata->node_min_pfn,
279 eidx + bdata->node_min_pfn);
281 if (bdata->hint_idx > sidx)
282 bdata->hint_idx = sidx;
284 for (idx = sidx; idx < eidx; idx++)
285 if (!test_and_clear_bit(idx, bdata->node_bootmem_map))
286 BUG();
289 static int __init __reserve(bootmem_data_t *bdata, unsigned long sidx,
290 unsigned long eidx, int flags)
292 unsigned long idx;
293 int exclusive = flags & BOOTMEM_EXCLUSIVE;
295 bdebug("nid=%td start=%lx end=%lx flags=%x\n",
296 bdata - bootmem_node_data,
297 sidx + bdata->node_min_pfn,
298 eidx + bdata->node_min_pfn,
299 flags);
301 for (idx = sidx; idx < eidx; idx++)
302 if (test_and_set_bit(idx, bdata->node_bootmem_map)) {
303 if (exclusive) {
304 __free(bdata, sidx, idx);
305 return -EBUSY;
307 bdebug("silent double reserve of PFN %lx\n",
308 idx + bdata->node_min_pfn);
310 return 0;
313 static int __init mark_bootmem_node(bootmem_data_t *bdata,
314 unsigned long start, unsigned long end,
315 int reserve, int flags)
317 unsigned long sidx, eidx;
319 bdebug("nid=%td start=%lx end=%lx reserve=%d flags=%x\n",
320 bdata - bootmem_node_data, start, end, reserve, flags);
322 BUG_ON(start < bdata->node_min_pfn);
323 BUG_ON(end > bdata->node_low_pfn);
325 sidx = start - bdata->node_min_pfn;
326 eidx = end - bdata->node_min_pfn;
328 if (reserve)
329 return __reserve(bdata, sidx, eidx, flags);
330 else
331 __free(bdata, sidx, eidx);
332 return 0;
335 static int __init mark_bootmem(unsigned long start, unsigned long end,
336 int reserve, int flags)
338 unsigned long pos;
339 bootmem_data_t *bdata;
341 pos = start;
342 list_for_each_entry(bdata, &bdata_list, list) {
343 int err;
344 unsigned long max;
346 if (pos < bdata->node_min_pfn ||
347 pos >= bdata->node_low_pfn) {
348 BUG_ON(pos != start);
349 continue;
352 max = min(bdata->node_low_pfn, end);
354 err = mark_bootmem_node(bdata, pos, max, reserve, flags);
355 if (reserve && err) {
356 mark_bootmem(start, pos, 0, 0);
357 return err;
360 if (max == end)
361 return 0;
362 pos = bdata->node_low_pfn;
364 BUG();
368 * free_bootmem_node - mark a page range as usable
369 * @pgdat: node the range resides on
370 * @physaddr: starting address of the range
371 * @size: size of the range in bytes
373 * Partial pages will be considered reserved and left as they are.
375 * The range must reside completely on the specified node.
377 void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
378 unsigned long size)
380 unsigned long start, end;
382 kmemleak_free_part(__va(physaddr), size);
384 start = PFN_UP(physaddr);
385 end = PFN_DOWN(physaddr + size);
387 mark_bootmem_node(pgdat->bdata, start, end, 0, 0);
391 * free_bootmem - mark a page range as usable
392 * @addr: starting address of the range
393 * @size: size of the range in bytes
395 * Partial pages will be considered reserved and left as they are.
397 * The range must be contiguous but may span node boundaries.
399 void __init free_bootmem(unsigned long addr, unsigned long size)
401 unsigned long start, end;
403 kmemleak_free_part(__va(addr), size);
405 start = PFN_UP(addr);
406 end = PFN_DOWN(addr + size);
408 mark_bootmem(start, end, 0, 0);
412 * reserve_bootmem_node - mark a page range as reserved
413 * @pgdat: node the range resides on
414 * @physaddr: starting address of the range
415 * @size: size of the range in bytes
416 * @flags: reservation flags (see linux/bootmem.h)
418 * Partial pages will be reserved.
420 * The range must reside completely on the specified node.
422 int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
423 unsigned long size, int flags)
425 unsigned long start, end;
427 start = PFN_DOWN(physaddr);
428 end = PFN_UP(physaddr + size);
430 return mark_bootmem_node(pgdat->bdata, start, end, 1, flags);
434 * reserve_bootmem - mark a page range as reserved
435 * @addr: starting address of the range
436 * @size: size of the range in bytes
437 * @flags: reservation flags (see linux/bootmem.h)
439 * Partial pages will be reserved.
441 * The range must be contiguous but may span node boundaries.
443 int __init reserve_bootmem(unsigned long addr, unsigned long size,
444 int flags)
446 unsigned long start, end;
448 start = PFN_DOWN(addr);
449 end = PFN_UP(addr + size);
451 return mark_bootmem(start, end, 1, flags);
454 int __weak __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
455 int flags)
457 return reserve_bootmem(phys, len, flags);
460 static unsigned long __init align_idx(struct bootmem_data *bdata,
461 unsigned long idx, unsigned long step)
463 unsigned long base = bdata->node_min_pfn;
466 * Align the index with respect to the node start so that the
467 * combination of both satisfies the requested alignment.
470 return ALIGN(base + idx, step) - base;
473 static unsigned long __init align_off(struct bootmem_data *bdata,
474 unsigned long off, unsigned long align)
476 unsigned long base = PFN_PHYS(bdata->node_min_pfn);
478 /* Same as align_idx for byte offsets */
480 return ALIGN(base + off, align) - base;
483 static void * __init alloc_bootmem_bdata(struct bootmem_data *bdata,
484 unsigned long size, unsigned long align,
485 unsigned long goal, unsigned long limit)
487 unsigned long fallback = 0;
488 unsigned long min, max, start, sidx, midx, step;
490 bdebug("nid=%td size=%lx [%lu pages] align=%lx goal=%lx limit=%lx\n",
491 bdata - bootmem_node_data, size, PAGE_ALIGN(size) >> PAGE_SHIFT,
492 align, goal, limit);
494 BUG_ON(!size);
495 BUG_ON(align & (align - 1));
496 BUG_ON(limit && goal + size > limit);
498 if (!bdata->node_bootmem_map)
499 return NULL;
501 min = bdata->node_min_pfn;
502 max = bdata->node_low_pfn;
504 goal >>= PAGE_SHIFT;
505 limit >>= PAGE_SHIFT;
507 if (limit && max > limit)
508 max = limit;
509 if (max <= min)
510 return NULL;
512 step = max(align >> PAGE_SHIFT, 1UL);
514 if (goal && min < goal && goal < max)
515 start = ALIGN(goal, step);
516 else
517 start = ALIGN(min, step);
519 sidx = start - bdata->node_min_pfn;
520 midx = max - bdata->node_min_pfn;
522 if (bdata->hint_idx > sidx) {
524 * Handle the valid case of sidx being zero and still
525 * catch the fallback below.
527 fallback = sidx + 1;
528 sidx = align_idx(bdata, bdata->hint_idx, step);
531 while (1) {
532 int merge;
533 void *region;
534 unsigned long eidx, i, start_off, end_off;
535 find_block:
536 sidx = find_next_zero_bit(bdata->node_bootmem_map, midx, sidx);
537 sidx = align_idx(bdata, sidx, step);
538 eidx = sidx + PFN_UP(size);
540 if (sidx >= midx || eidx > midx)
541 break;
543 for (i = sidx; i < eidx; i++)
544 if (test_bit(i, bdata->node_bootmem_map)) {
545 sidx = align_idx(bdata, i, step);
546 if (sidx == i)
547 sidx += step;
548 goto find_block;
551 if (bdata->last_end_off & (PAGE_SIZE - 1) &&
552 PFN_DOWN(bdata->last_end_off) + 1 == sidx)
553 start_off = align_off(bdata, bdata->last_end_off, align);
554 else
555 start_off = PFN_PHYS(sidx);
557 merge = PFN_DOWN(start_off) < sidx;
558 end_off = start_off + size;
560 bdata->last_end_off = end_off;
561 bdata->hint_idx = PFN_UP(end_off);
564 * Reserve the area now:
566 if (__reserve(bdata, PFN_DOWN(start_off) + merge,
567 PFN_UP(end_off), BOOTMEM_EXCLUSIVE))
568 BUG();
570 region = phys_to_virt(PFN_PHYS(bdata->node_min_pfn) +
571 start_off);
572 memset(region, 0, size);
574 * The min_count is set to 0 so that bootmem allocated blocks
575 * are never reported as leaks.
577 kmemleak_alloc(region, size, 0, 0);
578 return region;
581 if (fallback) {
582 sidx = align_idx(bdata, fallback - 1, step);
583 fallback = 0;
584 goto find_block;
587 return NULL;
590 static void * __init alloc_arch_preferred_bootmem(bootmem_data_t *bdata,
591 unsigned long size, unsigned long align,
592 unsigned long goal, unsigned long limit)
594 if (WARN_ON_ONCE(slab_is_available()))
595 return kzalloc(size, GFP_NOWAIT);
597 #ifdef CONFIG_HAVE_ARCH_BOOTMEM
599 bootmem_data_t *p_bdata;
601 p_bdata = bootmem_arch_preferred_node(bdata, size, align,
602 goal, limit);
603 if (p_bdata)
604 return alloc_bootmem_bdata(p_bdata, size, align,
605 goal, limit);
607 #endif
608 return NULL;
611 static void * __init alloc_bootmem_core(unsigned long size,
612 unsigned long align,
613 unsigned long goal,
614 unsigned long limit)
616 bootmem_data_t *bdata;
617 void *region;
619 region = alloc_arch_preferred_bootmem(NULL, size, align, goal, limit);
620 if (region)
621 return region;
623 list_for_each_entry(bdata, &bdata_list, list) {
624 if (goal && bdata->node_low_pfn <= PFN_DOWN(goal))
625 continue;
626 if (limit && bdata->node_min_pfn >= PFN_DOWN(limit))
627 break;
629 region = alloc_bootmem_bdata(bdata, size, align, goal, limit);
630 if (region)
631 return region;
634 return NULL;
637 static void * __init ___alloc_bootmem_nopanic(unsigned long size,
638 unsigned long align,
639 unsigned long goal,
640 unsigned long limit)
642 void *ptr;
644 restart:
645 ptr = alloc_bootmem_core(size, align, goal, limit);
646 if (ptr)
647 return ptr;
648 if (goal) {
649 goal = 0;
650 goto restart;
653 return NULL;
657 * __alloc_bootmem_nopanic - allocate boot memory without panicking
658 * @size: size of the request in bytes
659 * @align: alignment of the region
660 * @goal: preferred starting address of the region
662 * The goal is dropped if it can not be satisfied and the allocation will
663 * fall back to memory below @goal.
665 * Allocation may happen on any node in the system.
667 * Returns NULL on failure.
669 void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align,
670 unsigned long goal)
672 unsigned long limit = 0;
674 return ___alloc_bootmem_nopanic(size, align, goal, limit);
677 static void * __init ___alloc_bootmem(unsigned long size, unsigned long align,
678 unsigned long goal, unsigned long limit)
680 void *mem = ___alloc_bootmem_nopanic(size, align, goal, limit);
682 if (mem)
683 return mem;
685 * Whoops, we cannot satisfy the allocation request.
687 printk(KERN_ALERT "bootmem alloc of %lu bytes failed!\n", size);
688 panic("Out of memory");
689 return NULL;
693 * __alloc_bootmem - allocate boot memory
694 * @size: size of the request in bytes
695 * @align: alignment of the region
696 * @goal: preferred starting address of the region
698 * The goal is dropped if it can not be satisfied and the allocation will
699 * fall back to memory below @goal.
701 * Allocation may happen on any node in the system.
703 * The function panics if the request can not be satisfied.
705 void * __init __alloc_bootmem(unsigned long size, unsigned long align,
706 unsigned long goal)
708 unsigned long limit = 0;
710 return ___alloc_bootmem(size, align, goal, limit);
713 void * __init ___alloc_bootmem_node_nopanic(pg_data_t *pgdat,
714 unsigned long size, unsigned long align,
715 unsigned long goal, unsigned long limit)
717 void *ptr;
719 again:
720 ptr = alloc_arch_preferred_bootmem(pgdat->bdata, size,
721 align, goal, limit);
722 if (ptr)
723 return ptr;
725 /* do not panic in alloc_bootmem_bdata() */
726 if (limit && goal + size > limit)
727 limit = 0;
729 ptr = alloc_bootmem_bdata(pgdat->bdata, size, align, goal, limit);
730 if (ptr)
731 return ptr;
733 ptr = alloc_bootmem_core(size, align, goal, limit);
734 if (ptr)
735 return ptr;
737 if (goal) {
738 goal = 0;
739 goto again;
742 return NULL;
745 void * __init __alloc_bootmem_node_nopanic(pg_data_t *pgdat, unsigned long size,
746 unsigned long align, unsigned long goal)
748 if (WARN_ON_ONCE(slab_is_available()))
749 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
751 return ___alloc_bootmem_node_nopanic(pgdat, size, align, goal, 0);
754 void * __init ___alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
755 unsigned long align, unsigned long goal,
756 unsigned long limit)
758 void *ptr;
760 ptr = ___alloc_bootmem_node_nopanic(pgdat, size, align, goal, 0);
761 if (ptr)
762 return ptr;
764 printk(KERN_ALERT "bootmem alloc of %lu bytes failed!\n", size);
765 panic("Out of memory");
766 return NULL;
770 * __alloc_bootmem_node - allocate boot memory from a specific node
771 * @pgdat: node to allocate from
772 * @size: size of the request in bytes
773 * @align: alignment of the region
774 * @goal: preferred starting address of the region
776 * The goal is dropped if it can not be satisfied and the allocation will
777 * fall back to memory below @goal.
779 * Allocation may fall back to any node in the system if the specified node
780 * can not hold the requested memory.
782 * The function panics if the request can not be satisfied.
784 void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
785 unsigned long align, unsigned long goal)
787 if (WARN_ON_ONCE(slab_is_available()))
788 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
790 return ___alloc_bootmem_node(pgdat, size, align, goal, 0);
793 void * __init __alloc_bootmem_node_high(pg_data_t *pgdat, unsigned long size,
794 unsigned long align, unsigned long goal)
796 #ifdef MAX_DMA32_PFN
797 unsigned long end_pfn;
799 if (WARN_ON_ONCE(slab_is_available()))
800 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
802 /* update goal according ...MAX_DMA32_PFN */
803 end_pfn = pgdat->node_start_pfn + pgdat->node_spanned_pages;
805 if (end_pfn > MAX_DMA32_PFN + (128 >> (20 - PAGE_SHIFT)) &&
806 (goal >> PAGE_SHIFT) < MAX_DMA32_PFN) {
807 void *ptr;
808 unsigned long new_goal;
810 new_goal = MAX_DMA32_PFN << PAGE_SHIFT;
811 ptr = alloc_bootmem_bdata(pgdat->bdata, size, align,
812 new_goal, 0);
813 if (ptr)
814 return ptr;
816 #endif
818 return __alloc_bootmem_node(pgdat, size, align, goal);
822 #ifndef ARCH_LOW_ADDRESS_LIMIT
823 #define ARCH_LOW_ADDRESS_LIMIT 0xffffffffUL
824 #endif
827 * __alloc_bootmem_low - allocate low boot memory
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 happen on any node in the system.
837 * The function panics if the request can not be satisfied.
839 void * __init __alloc_bootmem_low(unsigned long size, unsigned long align,
840 unsigned long goal)
842 return ___alloc_bootmem(size, align, goal, ARCH_LOW_ADDRESS_LIMIT);
846 * __alloc_bootmem_low_node - allocate low boot memory from a specific node
847 * @pgdat: node to allocate from
848 * @size: size of the request in bytes
849 * @align: alignment of the region
850 * @goal: preferred starting address of the region
852 * The goal is dropped if it can not be satisfied and the allocation will
853 * fall back to memory below @goal.
855 * Allocation may fall back to any node in the system if the specified node
856 * can not hold the requested memory.
858 * The function panics if the request can not be satisfied.
860 void * __init __alloc_bootmem_low_node(pg_data_t *pgdat, unsigned long size,
861 unsigned long align, unsigned long goal)
863 if (WARN_ON_ONCE(slab_is_available()))
864 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
866 return ___alloc_bootmem_node(pgdat, size, align,
867 goal, ARCH_LOW_ADDRESS_LIMIT);