[deliverable/linux.git] / mm / nobootmem.c

/*
 *  bootmem - A boot-time physical memory allocator and configurator
 *
 *  Copyright (C) 1999 Ingo Molnar
 *                1999 Kanoj Sarcar, SGI
 *                2008 Johannes Weiner
 *
 * Access to this subsystem has to be serialized externally (which is true
 * for the boot process anyway).
 */
#include <linux/init.h>
#include <linux/pfn.h>
#include <linux/slab.h>
#include <linux/bootmem.h>
#include <linux/export.h>
#include <linux/kmemleak.h>
#include <linux/range.h>
#include <linux/memblock.h>

#include <asm/bug.h>
#include <asm/io.h>
#include <asm/processor.h>

#include "internal.h"

#ifndef CONFIG_NEED_MULTIPLE_NODES
struct pglist_data __refdata contig_page_data;
EXPORT_SYMBOL(contig_page_data);
#endif

unsigned long max_low_pfn;
unsigned long min_low_pfn;
unsigned long max_pfn;

static void * __init __alloc_memory_core_early(int nid, u64 size, u64 align,
					u64 goal, u64 limit)
{
	void *ptr;
	u64 addr;

	if (limit > memblock.current_limit)
		limit = memblock.current_limit;

	addr = find_memory_core_early(nid, size, align, goal, limit);

	if (addr == MEMBLOCK_ERROR)
		return NULL;

	ptr = phys_to_virt(addr);
	memset(ptr, 0, size);
	memblock_x86_reserve_range(addr, addr + size, "BOOTMEM");
	/*
	 * The min_count is set to 0 so that bootmem allocated blocks
	 * are never reported as leaks.
	 */
	kmemleak_alloc(ptr, size, 0, 0);
	return ptr;
}

/*
 * free_bootmem_late - free bootmem pages directly to page allocator
 * @addr: starting address of the range
 * @size: size of the range in bytes
 *
 * This is only useful when the bootmem allocator has already been torn
 * down, but we are still initializing the system.  Pages are given directly
 * to the page allocator, no bootmem metadata is updated because it is gone.
 */
void __init free_bootmem_late(unsigned long addr, unsigned long size)
{
	unsigned long cursor, end;

	kmemleak_free_part(__va(addr), size);

	cursor = PFN_UP(addr);
	end = PFN_DOWN(addr + size);

	for (; cursor < end; cursor++) {
		__free_pages_bootmem(pfn_to_page(cursor), 0);
		totalram_pages++;
	}
}

static void __init __free_pages_memory(unsigned long start, unsigned long end)
{
	int i;
	unsigned long start_aligned, end_aligned;
	int order = ilog2(BITS_PER_LONG);

	start_aligned = (start + (BITS_PER_LONG - 1)) & ~(BITS_PER_LONG - 1);
	end_aligned = end & ~(BITS_PER_LONG - 1);

	if (end_aligned <= start_aligned) {
		for (i = start; i < end; i++)
			__free_pages_bootmem(pfn_to_page(i), 0);

		return;
	}

	for (i = start; i < start_aligned; i++)
		__free_pages_bootmem(pfn_to_page(i), 0);

	for (i = start_aligned; i < end_aligned; i += BITS_PER_LONG)
		__free_pages_bootmem(pfn_to_page(i), order);

	for (i = end_aligned; i < end; i++)
		__free_pages_bootmem(pfn_to_page(i), 0);
}

unsigned long __init free_all_memory_core_early(int nodeid)
{
	int i;
	u64 start, end;
	unsigned long count = 0;
	struct range *range = NULL;
	int nr_range;

	nr_range = get_free_all_memory_range(&range, nodeid);

	for (i = 0; i < nr_range; i++) {
		start = range[i].start;
		end = range[i].end;
		count += end - start;
		__free_pages_memory(start, end);
	}

	return count;
}

/**
 * free_all_bootmem_node - release a node's free pages to the buddy allocator
 * @pgdat: node to be released
 *
 * Returns the number of pages actually released.
 */
unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
{
	register_page_bootmem_info_node(pgdat);

	/* free_all_memory_core_early(MAX_NUMNODES) will be called later */
	return 0;
}

/**
 * free_all_bootmem - release free pages to the buddy allocator
 *
 * Returns the number of pages actually released.
 */
unsigned long __init free_all_bootmem(void)
{
	/*
	 * We need to use MAX_NUMNODES instead of NODE_DATA(0)->node_id
	 *  because in some case like Node0 doesn't have RAM installed
	 *  low ram will be on Node1
	 * Use MAX_NUMNODES will make sure all ranges in early_node_map[]
	 *  will be used instead of only Node0 related
	 */
	return free_all_memory_core_early(MAX_NUMNODES);
}

/**
 * free_bootmem_node - mark a page range as usable
 * @pgdat: node the range resides on
 * @physaddr: starting address of the range
 * @size: size of the range in bytes
 *
 * Partial pages will be considered reserved and left as they are.
 *
 * The range must reside completely on the specified node.
 */
void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
			      unsigned long size)
{
	kmemleak_free_part(__va(physaddr), size);
	memblock_x86_free_range(physaddr, physaddr + size);
}

/**
 * free_bootmem - mark a page range as usable
 * @addr: starting address of the range
 * @size: size of the range in bytes
 *
 * Partial pages will be considered reserved and left as they are.
 *
 * The range must be contiguous but may span node boundaries.
 */
void __init free_bootmem(unsigned long addr, unsigned long size)
{
	kmemleak_free_part(__va(addr), size);
	memblock_x86_free_range(addr, addr + size);
}

static void * __init ___alloc_bootmem_nopanic(unsigned long size,
					unsigned long align,
					unsigned long goal,
					unsigned long limit)
{
	void *ptr;

	if (WARN_ON_ONCE(slab_is_available()))
		return kzalloc(size, GFP_NOWAIT);

restart:

	ptr = __alloc_memory_core_early(MAX_NUMNODES, size, align, goal, limit);

	if (ptr)
		return ptr;

	if (goal != 0) {
		goal = 0;
		goto restart;
	}

	return NULL;
}

/**
 * __alloc_bootmem_nopanic - allocate boot memory without panicking
 * @size: size of the request in bytes
 * @align: alignment of the region
 * @goal: preferred starting address of the region
 *
 * The goal is dropped if it can not be satisfied and the allocation will
 * fall back to memory below @goal.
 *
 * Allocation may happen on any node in the system.
 *
 * Returns NULL on failure.
 */
void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align,
					unsigned long goal)
{
	unsigned long limit = -1UL;

	return ___alloc_bootmem_nopanic(size, align, goal, limit);
}

static void * __init ___alloc_bootmem(unsigned long size, unsigned long align,
					unsigned long goal, unsigned long limit)
{
	void *mem = ___alloc_bootmem_nopanic(size, align, goal, limit);

	if (mem)
		return mem;
	/*
	 * Whoops, we cannot satisfy the allocation request.
	 */
	printk(KERN_ALERT "bootmem alloc of %lu bytes failed!\n", size);
	panic("Out of memory");
	return NULL;
}

/**
 * __alloc_bootmem - allocate boot memory
 * @size: size of the request in bytes
 * @align: alignment of the region
 * @goal: preferred starting address of the region
 *
 * The goal is dropped if it can not be satisfied and the allocation will
 * fall back to memory below @goal.
 *
 * Allocation may happen on any node in the system.
 *
 * The function panics if the request can not be satisfied.
 */
void * __init __alloc_bootmem(unsigned long size, unsigned long align,
			      unsigned long goal)
{
	unsigned long limit = -1UL;

	return ___alloc_bootmem(size, align, goal, limit);
}

/**
 * __alloc_bootmem_node - allocate boot memory from a specific node
 * @pgdat: node to allocate from
 * @size: size of the request in bytes
 * @align: alignment of the region
 * @goal: preferred starting address of the region
 *
 * The goal is dropped if it can not be satisfied and the allocation will
 * fall back to memory below @goal.
 *
 * Allocation may fall back to any node in the system if the specified node
 * can not hold the requested memory.
 *
 * The function panics if the request can not be satisfied.
 */
void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
				   unsigned long align, unsigned long goal)
{
	void *ptr;

	if (WARN_ON_ONCE(slab_is_available()))
		return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);

	ptr = __alloc_memory_core_early(pgdat->node_id, size, align,
					 goal, -1ULL);
	if (ptr)
		return ptr;

	return __alloc_memory_core_early(MAX_NUMNODES, size, align,
					 goal, -1ULL);
}

void * __init __alloc_bootmem_node_high(pg_data_t *pgdat, unsigned long size,
				   unsigned long align, unsigned long goal)
{
	return __alloc_bootmem_node(pgdat, size, align, goal);
}

#ifdef CONFIG_SPARSEMEM
/**
 * alloc_bootmem_section - allocate boot memory from a specific section
 * @size: size of the request in bytes
 * @section_nr: sparse map section to allocate from
 *
 * Return NULL on failure.
 */
void * __init alloc_bootmem_section(unsigned long size,
				    unsigned long section_nr)
{
	unsigned long pfn, goal, limit;

	pfn = section_nr_to_pfn(section_nr);
	goal = pfn << PAGE_SHIFT;
	limit = section_nr_to_pfn(section_nr + 1) << PAGE_SHIFT;

	return __alloc_memory_core_early(early_pfn_to_nid(pfn), size,
					 SMP_CACHE_BYTES, goal, limit);
}
#endif

void * __init __alloc_bootmem_node_nopanic(pg_data_t *pgdat, unsigned long size,
				   unsigned long align, unsigned long goal)
{
	void *ptr;

	if (WARN_ON_ONCE(slab_is_available()))
		return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);

	ptr =  __alloc_memory_core_early(pgdat->node_id, size, align,
						 goal, -1ULL);
	if (ptr)
		return ptr;

	return __alloc_bootmem_nopanic(size, align, goal);
}

#ifndef ARCH_LOW_ADDRESS_LIMIT
#define ARCH_LOW_ADDRESS_LIMIT	0xffffffffUL
#endif

/**
 * __alloc_bootmem_low - allocate low boot memory
 * @size: size of the request in bytes
 * @align: alignment of the region
 * @goal: preferred starting address of the region
 *
 * The goal is dropped if it can not be satisfied and the allocation will
 * fall back to memory below @goal.
 *
 * Allocation may happen on any node in the system.
 *
 * The function panics if the request can not be satisfied.
 */
void * __init __alloc_bootmem_low(unsigned long size, unsigned long align,
				  unsigned long goal)
{
	return ___alloc_bootmem(size, align, goal, ARCH_LOW_ADDRESS_LIMIT);
}

/**
 * __alloc_bootmem_low_node - allocate low boot memory from a specific node
 * @pgdat: node to allocate from
 * @size: size of the request in bytes
 * @align: alignment of the region
 * @goal: preferred starting address of the region
 *
 * The goal is dropped if it can not be satisfied and the allocation will
 * fall back to memory below @goal.
 *
 * Allocation may fall back to any node in the system if the specified node
 * can not hold the requested memory.
 *
 * The function panics if the request can not be satisfied.
 */
void * __init __alloc_bootmem_low_node(pg_data_t *pgdat, unsigned long size,
				       unsigned long align, unsigned long goal)
{
	void *ptr;

	if (WARN_ON_ONCE(slab_is_available()))
		return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);

	ptr = __alloc_memory_core_early(pgdat->node_id, size, align,
				goal, ARCH_LOW_ADDRESS_LIMIT);
	if (ptr)
		return ptr;

	return  __alloc_memory_core_early(MAX_NUMNODES, size, align,
				goal, ARCH_LOW_ADDRESS_LIMIT);
}
Commit	Line	Data
09325873 YL	1	/*
	2	* bootmem - A boot-time physical memory allocator and configurator
	3	*
	4	* Copyright (C) 1999 Ingo Molnar
	5	* 1999 Kanoj Sarcar, SGI
	6	* 2008 Johannes Weiner
	7	*
	8	* Access to this subsystem has to be serialized externally (which is true
	9	* for the boot process anyway).
	10	*/
	11	#include <linux/init.h>
	12	#include <linux/pfn.h>
	13	#include <linux/slab.h>
	14	#include <linux/bootmem.h>
b95f1b31	15	#include <linux/export.h>
09325873 YL	16	#include <linux/kmemleak.h>
	17	#include <linux/range.h>
	18	#include <linux/memblock.h>
	19
	20	#include <asm/bug.h>
	21	#include <asm/io.h>
	22	#include <asm/processor.h>
	23
	24	#include "internal.h"
	25
e782ab42 YL	26	#ifndef CONFIG_NEED_MULTIPLE_NODES
	27	struct pglist_data __refdata contig_page_data;
	28	EXPORT_SYMBOL(contig_page_data);
	29	#endif
	30
09325873 YL	31	unsigned long max_low_pfn;
	32	unsigned long min_low_pfn;
	33	unsigned long max_pfn;
	34
8bc1f91e YL	35	static void * __init __alloc_memory_core_early(int nid, u64 size, u64 align,
	36	u64 goal, u64 limit)
	37	{
	38	void *ptr;
	39	u64 addr;
	40
	41	if (limit > memblock.current_limit)
	42	limit = memblock.current_limit;
	43
	44	addr = find_memory_core_early(nid, size, align, goal, limit);
	45
	46	if (addr == MEMBLOCK_ERROR)
	47	return NULL;
	48
	49	ptr = phys_to_virt(addr);
	50	memset(ptr, 0, size);
	51	memblock_x86_reserve_range(addr, addr + size, "BOOTMEM");
	52	/*
	53	* The min_count is set to 0 so that bootmem allocated blocks
	54	* are never reported as leaks.
	55	*/
	56	kmemleak_alloc(ptr, size, 0, 0);
	57	return ptr;
	58	}
	59
09325873 YL	60	/*
	61	* free_bootmem_late - free bootmem pages directly to page allocator
	62	* @addr: starting address of the range
	63	* @size: size of the range in bytes
	64	*
	65	* This is only useful when the bootmem allocator has already been torn
	66	* down, but we are still initializing the system. Pages are given directly
	67	* to the page allocator, no bootmem metadata is updated because it is gone.
	68	*/
	69	void __init free_bootmem_late(unsigned long addr, unsigned long size)
	70	{
	71	unsigned long cursor, end;
	72
	73	kmemleak_free_part(__va(addr), size);
	74
	75	cursor = PFN_UP(addr);
	76	end = PFN_DOWN(addr + size);
	77
	78	for (; cursor < end; cursor++) {
	79	__free_pages_bootmem(pfn_to_page(cursor), 0);
	80	totalram_pages++;
	81	}
	82	}
	83
	84	static void __init __free_pages_memory(unsigned long start, unsigned long end)
	85	{
	86	int i;
	87	unsigned long start_aligned, end_aligned;
	88	int order = ilog2(BITS_PER_LONG);
	89
	90	start_aligned = (start + (BITS_PER_LONG - 1)) & ~(BITS_PER_LONG - 1);
	91	end_aligned = end & ~(BITS_PER_LONG - 1);
	92
	93	if (end_aligned <= start_aligned) {
	94	for (i = start; i < end; i++)
	95	__free_pages_bootmem(pfn_to_page(i), 0);
	96
	97	return;
	98	}
	99
	100	for (i = start; i < start_aligned; i++)
	101	__free_pages_bootmem(pfn_to_page(i), 0);
	102
	103	for (i = start_aligned; i < end_aligned; i += BITS_PER_LONG)
	104	__free_pages_bootmem(pfn_to_page(i), order);
	105
	106	for (i = end_aligned; i < end; i++)
	107	__free_pages_bootmem(pfn_to_page(i), 0);
	108	}
	109
	110	unsigned long __init free_all_memory_core_early(int nodeid)
	111	{
	112	int i;
	113	u64 start, end;
	114	unsigned long count = 0;
	115	struct range *range = NULL;
	116	int nr_range;
	117
	118	nr_range = get_free_all_memory_range(&range, nodeid);
	119
	120	for (i = 0; i < nr_range; i++) {
	121	start = range[i].start;
	122	end = range[i].end;
	123	count += end - start;
124	__free_pages_memory(start, end);
125	}
126
127	return count;
128	}
129
130	/**
131	* free_all_bootmem_node - release a node's free pages to the buddy allocator
132	* @pgdat: node to be released
133	*
134	* Returns the number of pages actually released.
135	*/
136	unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
137	{
138	register_page_bootmem_info_node(pgdat);
139
140	/* free_all_memory_core_early(MAX_NUMNODES) will be called later */
141	return 0;
142	}
143
144	/**
145	* free_all_bootmem - release free pages to the buddy allocator
146	*
147	* Returns the number of pages actually released.
148	*/
149	unsigned long __init free_all_bootmem(void)
150	{
151	/*
152	* We need to use MAX_NUMNODES instead of NODE_DATA(0)->node_id
25985edc	153	* because in some case like Node0 doesn't have RAM installed
09325873 YL	154	* low ram will be on Node1
	155	* Use MAX_NUMNODES will make sure all ranges in early_node_map[]
	156	* will be used instead of only Node0 related
	157	*/
	158	return free_all_memory_core_early(MAX_NUMNODES);
	159	}
	160
	161	/**
	162	* free_bootmem_node - mark a page range as usable
	163	* @pgdat: node the range resides on
	164	* @physaddr: starting address of the range
	165	* @size: size of the range in bytes
	166	*
	167	* Partial pages will be considered reserved and left as they are.
	168	*
	169	* The range must reside completely on the specified node.
	170	*/
	171	void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
	172	unsigned long size)
	173	{
	174	kmemleak_free_part(__va(physaddr), size);
	175	memblock_x86_free_range(physaddr, physaddr + size);
	176	}
	177
	178	/**
	179	* free_bootmem - mark a page range as usable
	180	* @addr: starting address of the range
	181	* @size: size of the range in bytes
	182	*
	183	* Partial pages will be considered reserved and left as they are.
	184	*
	185	* The range must be contiguous but may span node boundaries.
	186	*/
	187	void __init free_bootmem(unsigned long addr, unsigned long size)
	188	{
	189	kmemleak_free_part(__va(addr), size);
	190	memblock_x86_free_range(addr, addr + size);
	191	}
	192
	193	static void * __init ___alloc_bootmem_nopanic(unsigned long size,
	194	unsigned long align,
	195	unsigned long goal,
	196	unsigned long limit)
	197	{
	198	void *ptr;
	199
	200	if (WARN_ON_ONCE(slab_is_available()))
	201	return kzalloc(size, GFP_NOWAIT);
	202
	203	restart:
	204
	205	ptr = __alloc_memory_core_early(MAX_NUMNODES, size, align, goal, limit);
	206
	207	if (ptr)
	208	return ptr;
	209
	210	if (goal != 0) {
	211	goal = 0;
	212	goto restart;
	213	}
	214
	215	return NULL;
	216	}
	217
218	/**
219	* __alloc_bootmem_nopanic - allocate boot memory without panicking
220	* @size: size of the request in bytes
221	* @align: alignment of the region
222	* @goal: preferred starting address of the region
223	*
224	* The goal is dropped if it can not be satisfied and the allocation will
225	* fall back to memory below @goal.
226	*
227	* Allocation may happen on any node in the system.
228	*
229	* Returns NULL on failure.
230	*/
231	void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align,
232	unsigned long goal)
233	{
234	unsigned long limit = -1UL;
235
236	return ___alloc_bootmem_nopanic(size, align, goal, limit);
237	}
238
239	static void * __init ___alloc_bootmem(unsigned long size, unsigned long align,
240	unsigned long goal, unsigned long limit)
241	{
242	void *mem = ___alloc_bootmem_nopanic(size, align, goal, limit);
243
244	if (mem)
245	return mem;
246	/*
247	* Whoops, we cannot satisfy the allocation request.
248	*/
249	printk(KERN_ALERT "bootmem alloc of %lu bytes failed!\n", size);
250	panic("Out of memory");
251	return NULL;
252	}
253
254	/**
255	* __alloc_bootmem - allocate boot memory
256	* @size: size of the request in bytes
257	* @align: alignment of the region
258	* @goal: preferred starting address of the region
259	*
260	* The goal is dropped if it can not be satisfied and the allocation will
261	* fall back to memory below @goal.
262	*
263	* Allocation may happen on any node in the system.
264	*
265	* The function panics if the request can not be satisfied.
266	*/
267	void * __init __alloc_bootmem(unsigned long size, unsigned long align,
268	unsigned long goal)
269	{
270	unsigned long limit = -1UL;
271
272	return ___alloc_bootmem(size, align, goal, limit);
273	}
274
275	/**
276	* __alloc_bootmem_node - allocate boot memory from a specific node
277	* @pgdat: node to allocate from
278	* @size: size of the request in bytes
279	* @align: alignment of the region
280	* @goal: preferred starting address of the region
281	*
282	* The goal is dropped if it can not be satisfied and the allocation will
283	* fall back to memory below @goal.
284	*
285	* Allocation may fall back to any node in the system if the specified node
286	* can not hold the requested memory.
287	*
288	* The function panics if the request can not be satisfied.
289	*/
290	void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
291	unsigned long align, unsigned long goal)
292	{
293	void *ptr;
294
295	if (WARN_ON_ONCE(slab_is_available()))
296	return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
297
298	ptr = __alloc_memory_core_early(pgdat->node_id, size, align,
299	goal, -1ULL);
300	if (ptr)
301	return ptr;
302
303	return __alloc_memory_core_early(MAX_NUMNODES, size, align,
304	goal, -1ULL);
305	}
306
307	void * __init __alloc_bootmem_node_high(pg_data_t *pgdat, unsigned long size,
308	unsigned long align, unsigned long goal)
309	{
09325873	310	return __alloc_bootmem_node(pgdat, size, align, goal);
09325873 YL	311	}
	312
	313	#ifdef CONFIG_SPARSEMEM
	314	/**
	315	* alloc_bootmem_section - allocate boot memory from a specific section
	316	* @size: size of the request in bytes
	317	* @section_nr: sparse map section to allocate from
	318	*
	319	* Return NULL on failure.
	320	*/
	321	void * __init alloc_bootmem_section(unsigned long size,
	322	unsigned long section_nr)
	323	{
	324	unsigned long pfn, goal, limit;
	325
	326	pfn = section_nr_to_pfn(section_nr);
	327	goal = pfn << PAGE_SHIFT;
	328	limit = section_nr_to_pfn(section_nr + 1) << PAGE_SHIFT;
	329
	330	return __alloc_memory_core_early(early_pfn_to_nid(pfn), size,
	331	SMP_CACHE_BYTES, goal, limit);
	332	}
	333	#endif
	334
	335	void * __init __alloc_bootmem_node_nopanic(pg_data_t *pgdat, unsigned long size,
	336	unsigned long align, unsigned long goal)
	337	{
	338	void *ptr;
	339
	340	if (WARN_ON_ONCE(slab_is_available()))
	341	return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
	342
	343	ptr = __alloc_memory_core_early(pgdat->node_id, size, align,
	344	goal, -1ULL);
	345	if (ptr)
	346	return ptr;
	347
	348	return __alloc_bootmem_nopanic(size, align, goal);
	349	}
	350
	351	#ifndef ARCH_LOW_ADDRESS_LIMIT
	352	#define ARCH_LOW_ADDRESS_LIMIT 0xffffffffUL
	353	#endif
	354
	355	/**
	356	* __alloc_bootmem_low - allocate low boot memory
	357	* @size: size of the request in bytes
	358	* @align: alignment of the region
	359	* @goal: preferred starting address of the region
	360	*
	361	* The goal is dropped if it can not be satisfied and the allocation will
	362	* fall back to memory below @goal.
	363	*
	364	* Allocation may happen on any node in the system.
	365	*
	366	* The function panics if the request can not be satisfied.
	367	*/
	368	void * __init __alloc_bootmem_low(unsigned long size, unsigned long align,
	369	unsigned long goal)
	370	{
	371	return ___alloc_bootmem(size, align, goal, ARCH_LOW_ADDRESS_LIMIT);
	372	}
	373
	374	/**
375	* __alloc_bootmem_low_node - allocate low boot memory from a specific node
376	* @pgdat: node to allocate from
377	* @size: size of the request in bytes
378	* @align: alignment of the region
379	* @goal: preferred starting address of the region
380	*
381	* The goal is dropped if it can not be satisfied and the allocation will
382	* fall back to memory below @goal.
383	*
384	* Allocation may fall back to any node in the system if the specified node
385	* can not hold the requested memory.
386	*
387	* The function panics if the request can not be satisfied.
388	*/
389	void * __init __alloc_bootmem_low_node(pg_data_t *pgdat, unsigned long size,
390	unsigned long align, unsigned long goal)
391	{
392	void *ptr;
393
394	if (WARN_ON_ONCE(slab_is_available()))
395	return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
396
397	ptr = __alloc_memory_core_early(pgdat->node_id, size, align,
398	goal, ARCH_LOW_ADDRESS_LIMIT);
399	if (ptr)
400	return ptr;
401
402	return __alloc_memory_core_early(MAX_NUMNODES, size, align,
403	goal, ARCH_LOW_ADDRESS_LIMIT);
404	}