[linux.git] / mm / bootmem.c

/*
 *  linux/mm/bootmem.c
 *
 *  Copyright (C) 1999 Ingo Molnar
 *  Discontiguous memory support, Kanoj Sarcar, SGI, Nov 1999
 *
 *  simple boot-time physical memory area allocator and
 *  free memory collector. It's used to deal with reserved
 *  system memory and memory holes as well.
 */
#include <linux/init.h>
#include <linux/pfn.h>
#include <linux/bootmem.h>
#include <linux/module.h>

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

#include "internal.h"

/*
 * Access to this subsystem has to be serialized externally. (this is
 * true for the boot process anyway)
 */
unsigned long max_low_pfn;
unsigned long min_low_pfn;
unsigned long max_pfn;

static LIST_HEAD(bdata_list);
#ifdef CONFIG_CRASH_DUMP
/*
 * If we have booted due to a crash, max_pfn will be a very low value. We need
 * to know the amount of memory that the previous kernel used.
 */
unsigned long saved_max_pfn;
#endif

/* return the number of _pages_ that will be allocated for the boot bitmap */
unsigned long __init bootmem_bootmap_pages(unsigned long pages)
{
	unsigned long mapsize;

	mapsize = (pages+7)/8;
	mapsize = (mapsize + ~PAGE_MASK) & PAGE_MASK;
	mapsize >>= PAGE_SHIFT;

	return mapsize;
}

/*
 * link bdata in order
 */
static void __init link_bootmem(bootmem_data_t *bdata)
{
	bootmem_data_t *ent;

	if (list_empty(&bdata_list)) {
		list_add(&bdata->list, &bdata_list);
		return;
	}
	/* insert in order */
	list_for_each_entry(ent, &bdata_list, list) {
		if (bdata->node_boot_start < ent->node_boot_start) {
			list_add_tail(&bdata->list, &ent->list);
			return;
		}
	}
	list_add_tail(&bdata->list, &bdata_list);
}

/*
 * Given an initialised bdata, it returns the size of the boot bitmap
 */
static unsigned long __init get_mapsize(bootmem_data_t *bdata)
{
	unsigned long mapsize;
	unsigned long start = PFN_DOWN(bdata->node_boot_start);
	unsigned long end = bdata->node_low_pfn;

	mapsize = ((end - start) + 7) / 8;
	return ALIGN(mapsize, sizeof(long));
}

/*
 * Called once to set up the allocator itself.
 */
static unsigned long __init init_bootmem_core(pg_data_t *pgdat,
	unsigned long mapstart, unsigned long start, unsigned long end)
{
	bootmem_data_t *bdata = pgdat->bdata;
	unsigned long mapsize;

	bdata->node_bootmem_map = phys_to_virt(PFN_PHYS(mapstart));
	bdata->node_boot_start = PFN_PHYS(start);
	bdata->node_low_pfn = end;
	link_bootmem(bdata);

	/*
	 * Initially all pages are reserved - setup_arch() has to
	 * register free RAM areas explicitly.
	 */
	mapsize = get_mapsize(bdata);
	memset(bdata->node_bootmem_map, 0xff, mapsize);

	return mapsize;
}

/*
 * Marks a particular physical memory range as unallocatable. Usable RAM
 * might be used for boot-time allocations - or it might get added
 * to the free page pool later on.
 */
static void __init reserve_bootmem_core(bootmem_data_t *bdata, unsigned long addr,
					unsigned long size)
{
	unsigned long sidx, eidx;
	unsigned long i;

	/*
	 * round up, partially reserved pages are considered
	 * fully reserved.
	 */
	BUG_ON(!size);
	BUG_ON(PFN_DOWN(addr) >= bdata->node_low_pfn);
	BUG_ON(PFN_UP(addr + size) > bdata->node_low_pfn);

	sidx = PFN_DOWN(addr - bdata->node_boot_start);
	eidx = PFN_UP(addr + size - bdata->node_boot_start);

	for (i = sidx; i < eidx; i++)
		if (test_and_set_bit(i, bdata->node_bootmem_map)) {
#ifdef CONFIG_DEBUG_BOOTMEM
			printk("hm, page %08lx reserved twice.\n", i*PAGE_SIZE);
#endif
		}
}

static void __init free_bootmem_core(bootmem_data_t *bdata, unsigned long addr,
				     unsigned long size)
{
	unsigned long sidx, eidx;
	unsigned long i;

	/*
	 * round down end of usable mem, partially free pages are
	 * considered reserved.
	 */
	BUG_ON(!size);
	BUG_ON(PFN_DOWN(addr + size) > bdata->node_low_pfn);

	if (addr < bdata->last_success)
		bdata->last_success = addr;

	/*
	 * Round up the beginning of the address.
	 */
	sidx = PFN_UP(addr) - PFN_DOWN(bdata->node_boot_start);
	eidx = PFN_DOWN(addr + size - bdata->node_boot_start);

	for (i = sidx; i < eidx; i++) {
		if (unlikely(!test_and_clear_bit(i, bdata->node_bootmem_map)))
			BUG();
	}
}

/*
 * We 'merge' subsequent allocations to save space. We might 'lose'
 * some fraction of a page if allocations cannot be satisfied due to
 * size constraints on boxes where there is physical RAM space
 * fragmentation - in these cases (mostly large memory boxes) this
 * is not a problem.
 *
 * On low memory boxes we get it right in 100% of the cases.
 *
 * alignment has to be a power of 2 value.
 *
 * NOTE:  This function is _not_ reentrant.
 */
void * __init
__alloc_bootmem_core(struct bootmem_data *bdata, unsigned long size,
	      unsigned long align, unsigned long goal, unsigned long limit)
{
	unsigned long offset, remaining_size, areasize, preferred;
	unsigned long i, start = 0, incr, eidx, end_pfn;
	void *ret;

	if (!size) {
		printk("__alloc_bootmem_core(): zero-sized request\n");
		BUG();
	}
	BUG_ON(align & (align-1));

	if (limit && bdata->node_boot_start >= limit)
		return NULL;

	/* on nodes without memory - bootmem_map is NULL */
	if (!bdata->node_bootmem_map)
		return NULL;

	end_pfn = bdata->node_low_pfn;
	limit = PFN_DOWN(limit);
	if (limit && end_pfn > limit)
		end_pfn = limit;

	eidx = end_pfn - PFN_DOWN(bdata->node_boot_start);
	offset = 0;
	if (align && (bdata->node_boot_start & (align - 1UL)) != 0)
		offset = align - (bdata->node_boot_start & (align - 1UL));
	offset = PFN_DOWN(offset);

	/*
	 * We try to allocate bootmem pages above 'goal'
	 * first, then we try to allocate lower pages.
	 */
	if (goal && goal >= bdata->node_boot_start && PFN_DOWN(goal) < end_pfn) {
		preferred = goal - bdata->node_boot_start;

		if (bdata->last_success >= preferred)
			if (!limit || (limit && limit > bdata->last_success))
				preferred = bdata->last_success;
	} else
		preferred = 0;

	preferred = PFN_DOWN(ALIGN(preferred, align)) + offset;
	areasize = (size + PAGE_SIZE-1) / PAGE_SIZE;
	incr = align >> PAGE_SHIFT ? : 1;

restart_scan:
	for (i = preferred; i < eidx; i += incr) {
		unsigned long j;
		i = find_next_zero_bit(bdata->node_bootmem_map, eidx, i);
		i = ALIGN(i, incr);
		if (i >= eidx)
			break;
		if (test_bit(i, bdata->node_bootmem_map))
			continue;
		for (j = i + 1; j < i + areasize; ++j) {
			if (j >= eidx)
				goto fail_block;
			if (test_bit(j, bdata->node_bootmem_map))
				goto fail_block;
		}
		start = i;
		goto found;
	fail_block:
		i = ALIGN(j, incr);
	}

	if (preferred > offset) {
		preferred = offset;
		goto restart_scan;
	}
	return NULL;

found:
	bdata->last_success = PFN_PHYS(start);
	BUG_ON(start >= eidx);

	/*
	 * Is the next page of the previous allocation-end the start
	 * of this allocation's buffer? If yes then we can 'merge'
	 * the previous partial page with this allocation.
	 */
	if (align < PAGE_SIZE &&
	    bdata->last_offset && bdata->last_pos+1 == start) {
		offset = ALIGN(bdata->last_offset, align);
		BUG_ON(offset > PAGE_SIZE);
		remaining_size = PAGE_SIZE - offset;
		if (size < remaining_size) {
			areasize = 0;
			/* last_pos unchanged */
			bdata->last_offset = offset + size;
			ret = phys_to_virt(bdata->last_pos * PAGE_SIZE +
					   offset +
					   bdata->node_boot_start);
		} else {
			remaining_size = size - remaining_size;
			areasize = (remaining_size + PAGE_SIZE-1) / PAGE_SIZE;
			ret = phys_to_virt(bdata->last_pos * PAGE_SIZE +
					   offset +
					   bdata->node_boot_start);
			bdata->last_pos = start + areasize - 1;
			bdata->last_offset = remaining_size;
		}
		bdata->last_offset &= ~PAGE_MASK;
	} else {
		bdata->last_pos = start + areasize - 1;
		bdata->last_offset = size & ~PAGE_MASK;
		ret = phys_to_virt(start * PAGE_SIZE + bdata->node_boot_start);
	}

	/*
	 * Reserve the area now:
	 */
	for (i = start; i < start + areasize; i++)
		if (unlikely(test_and_set_bit(i, bdata->node_bootmem_map)))
			BUG();
	memset(ret, 0, size);
	return ret;
}

static unsigned long __init free_all_bootmem_core(pg_data_t *pgdat)
{
	struct page *page;
	unsigned long pfn;
	bootmem_data_t *bdata = pgdat->bdata;
	unsigned long i, count, total = 0;
	unsigned long idx;
	unsigned long *map; 
	int gofast = 0;

	BUG_ON(!bdata->node_bootmem_map);

	count = 0;
	/* first extant page of the node */
	pfn = PFN_DOWN(bdata->node_boot_start);
	idx = bdata->node_low_pfn - pfn;
	map = bdata->node_bootmem_map;
	/* Check physaddr is O(LOG2(BITS_PER_LONG)) page aligned */
	if (bdata->node_boot_start == 0 ||
	    ffs(bdata->node_boot_start) - PAGE_SHIFT > ffs(BITS_PER_LONG))
		gofast = 1;
	for (i = 0; i < idx; ) {
		unsigned long v = ~map[i / BITS_PER_LONG];

		if (gofast && v == ~0UL) {
			int order;

			page = pfn_to_page(pfn);
			count += BITS_PER_LONG;
			order = ffs(BITS_PER_LONG) - 1;
			__free_pages_bootmem(page, order);
			i += BITS_PER_LONG;
			page += BITS_PER_LONG;
		} else if (v) {
			unsigned long m;

			page = pfn_to_page(pfn);
			for (m = 1; m && i < idx; m<<=1, page++, i++) {
				if (v & m) {
					count++;
					__free_pages_bootmem(page, 0);
				}
			}
		} else {
			i += BITS_PER_LONG;
		}
		pfn += BITS_PER_LONG;
	}
	total += count;

	/*
	 * Now free the allocator bitmap itself, it's not
	 * needed anymore:
	 */
	page = virt_to_page(bdata->node_bootmem_map);
	count = 0;
	idx = (get_mapsize(bdata) + PAGE_SIZE-1) >> PAGE_SHIFT;
	for (i = 0; i < idx; i++, page++) {
		__free_pages_bootmem(page, 0);
		count++;
	}
	total += count;
	bdata->node_bootmem_map = NULL;

	return total;
}

unsigned long __init init_bootmem_node(pg_data_t *pgdat, unsigned long freepfn,
				unsigned long startpfn, unsigned long endpfn)
{
	return init_bootmem_core(pgdat, freepfn, startpfn, endpfn);
}

void __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
				 unsigned long size)
{
	reserve_bootmem_core(pgdat->bdata, physaddr, size);
}

void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
			      unsigned long size)
{
	free_bootmem_core(pgdat->bdata, physaddr, size);
}

unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
{
	return free_all_bootmem_core(pgdat);
}

unsigned long __init init_bootmem(unsigned long start, unsigned long pages)
{
	max_low_pfn = pages;
	min_low_pfn = start;
	return init_bootmem_core(NODE_DATA(0), start, 0, pages);
}

#ifndef CONFIG_HAVE_ARCH_BOOTMEM_NODE
void __init reserve_bootmem(unsigned long addr, unsigned long size)
{
	reserve_bootmem_core(NODE_DATA(0)->bdata, addr, size);
}
#endif /* !CONFIG_HAVE_ARCH_BOOTMEM_NODE */

void __init free_bootmem(unsigned long addr, unsigned long size)
{
	free_bootmem_core(NODE_DATA(0)->bdata, addr, size);
}

unsigned long __init free_all_bootmem(void)
{
	return free_all_bootmem_core(NODE_DATA(0));
}

void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align,
				      unsigned long goal)
{
	bootmem_data_t *bdata;
	void *ptr;

	list_for_each_entry(bdata, &bdata_list, list) {
		ptr = __alloc_bootmem_core(bdata, size, align, goal, 0);
		if (ptr)
			return ptr;
	}
	return NULL;
}

void * __init __alloc_bootmem(unsigned long size, unsigned long align,
			      unsigned long goal)
{
	void *mem = __alloc_bootmem_nopanic(size,align,goal);

	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;
}


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

	ptr = __alloc_bootmem_core(pgdat->bdata, size, align, goal, 0);
	if (ptr)
		return ptr;

	return __alloc_bootmem(size, align, goal);
}

#ifndef ARCH_LOW_ADDRESS_LIMIT
#define ARCH_LOW_ADDRESS_LIMIT	0xffffffffUL
#endif

void * __init __alloc_bootmem_low(unsigned long size, unsigned long align,
				  unsigned long goal)
{
	bootmem_data_t *bdata;
	void *ptr;

	list_for_each_entry(bdata, &bdata_list, list) {
		ptr = __alloc_bootmem_core(bdata, size, align, goal,
						ARCH_LOW_ADDRESS_LIMIT);
		if (ptr)
			return ptr;
	}

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

void * __init __alloc_bootmem_low_node(pg_data_t *pgdat, unsigned long size,
				       unsigned long align, unsigned long goal)
{
	return __alloc_bootmem_core(pgdat->bdata, size, align, goal,
				    ARCH_LOW_ADDRESS_LIMIT);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/mm/bootmem.c
	3	*
	4	* Copyright (C) 1999 Ingo Molnar
	5	* Discontiguous memory support, Kanoj Sarcar, SGI, Nov 1999
	6	*
	7	* simple boot-time physical memory area allocator and
	8	* free memory collector. It's used to deal with reserved
	9	* system memory and memory holes as well.
	10	*/
1da177e4	11	#include <linux/init.h>
bbc7b92e	12	#include <linux/pfn.h>
1da177e4	13	#include <linux/bootmem.h>
1da177e4	14	#include <linux/module.h>
e786e86a FBH	15
e786e86a FBH	16	#include <asm/bug.h>
1da177e4	17	#include <asm/io.h>
dfd54cbc	18	#include <asm/processor.h>
e786e86a	19
1da177e4 LT	20	#include "internal.h"
	21
	22	/*
	23	* Access to this subsystem has to be serialized externally. (this is
	24	* true for the boot process anyway)
	25	*/
	26	unsigned long max_low_pfn;
	27	unsigned long min_low_pfn;
	28	unsigned long max_pfn;
	29
679bc9fb	30	static LIST_HEAD(bdata_list);
92aa63a5 VG	31	#ifdef CONFIG_CRASH_DUMP
	32	/*
	33	* If we have booted due to a crash, max_pfn will be a very low value. We need
	34	* to know the amount of memory that the previous kernel used.
	35	*/
	36	unsigned long saved_max_pfn;
	37	#endif
	38
1da177e4	39	/* return the number of _pages_ that will be allocated for the boot bitmap */
f71bf0ca	40	unsigned long __init bootmem_bootmap_pages(unsigned long pages)
1da177e4 LT	41	{
	42	unsigned long mapsize;
	43
	44	mapsize = (pages+7)/8;
	45	mapsize = (mapsize + ~PAGE_MASK) & PAGE_MASK;
	46	mapsize >>= PAGE_SHIFT;
	47
	48	return mapsize;
	49	}
f71bf0ca	50
679bc9fb KH	51	/*
	52	* link bdata in order
	53	*/
69d49e68	54	static void __init link_bootmem(bootmem_data_t *bdata)
679bc9fb KH	55	{
679bc9fb KH	56	bootmem_data_t *ent;
f71bf0ca	57
679bc9fb KH	58	if (list_empty(&bdata_list)) {
	59	list_add(&bdata->list, &bdata_list);
	60	return;
	61	}
	62	/* insert in order */
	63	list_for_each_entry(ent, &bdata_list, list) {
	64	if (bdata->node_boot_start < ent->node_boot_start) {
	65	list_add_tail(&bdata->list, &ent->list);
	66	return;
	67	}
	68	}
	69	list_add_tail(&bdata->list, &bdata_list);
679bc9fb KH	70	}
679bc9fb KH	71
bbc7b92e FBH	72	/*
	73	* Given an initialised bdata, it returns the size of the boot bitmap
	74	*/
	75	static unsigned long __init get_mapsize(bootmem_data_t *bdata)
	76	{
	77	unsigned long mapsize;
	78	unsigned long start = PFN_DOWN(bdata->node_boot_start);
	79	unsigned long end = bdata->node_low_pfn;
	80
	81	mapsize = ((end - start) + 7) / 8;
	82	return ALIGN(mapsize, sizeof(long));
	83	}
1da177e4 LT	84
	85	/*
	86	* Called once to set up the allocator itself.
	87	*/
f71bf0ca	88	static unsigned long __init init_bootmem_core(pg_data_t *pgdat,
1da177e4 LT	89	unsigned long mapstart, unsigned long start, unsigned long end)
	90	{
	91	bootmem_data_t *bdata = pgdat->bdata;
bbc7b92e	92	unsigned long mapsize;
1da177e4	93
bbc7b92e FBH	94	bdata->node_bootmem_map = phys_to_virt(PFN_PHYS(mapstart));
bbc7b92e FBH	95	bdata->node_boot_start = PFN_PHYS(start);
1da177e4	96	bdata->node_low_pfn = end;
679bc9fb	97	link_bootmem(bdata);
1da177e4 LT	98
	99	/*
	100	* Initially all pages are reserved - setup_arch() has to
	101	* register free RAM areas explicitly.
	102	*/
bbc7b92e	103	mapsize = get_mapsize(bdata);
1da177e4 LT	104	memset(bdata->node_bootmem_map, 0xff, mapsize);
	105
	106	return mapsize;
	107	}
	108
	109	/*
	110	* Marks a particular physical memory range as unallocatable. Usable RAM
	111	* might be used for boot-time allocations - or it might get added
	112	* to the free page pool later on.
	113	*/
bb0923a6 FBH	114	static void __init reserve_bootmem_core(bootmem_data_t *bdata, unsigned long addr,
bb0923a6 FBH	115	unsigned long size)
1da177e4	116	{
bbc7b92e	117	unsigned long sidx, eidx;
1da177e4	118	unsigned long i;
bbc7b92e	119
1da177e4 LT	120	/*
	121	* round up, partially reserved pages are considered
	122	* fully reserved.
	123	*/
1da177e4	124	BUG_ON(!size);
bbc7b92e FBH	125	BUG_ON(PFN_DOWN(addr) >= bdata->node_low_pfn);
	126	BUG_ON(PFN_UP(addr + size) > bdata->node_low_pfn);
	127
	128	sidx = PFN_DOWN(addr - bdata->node_boot_start);
	129	eidx = PFN_UP(addr + size - bdata->node_boot_start);
1da177e4 LT	130
	131	for (i = sidx; i < eidx; i++)
	132	if (test_and_set_bit(i, bdata->node_bootmem_map)) {
	133	#ifdef CONFIG_DEBUG_BOOTMEM
	134	printk("hm, page %08lx reserved twice.\n", i*PAGE_SIZE);
	135	#endif
	136	}
	137	}
	138
bb0923a6 FBH	139	static void __init free_bootmem_core(bootmem_data_t *bdata, unsigned long addr,
bb0923a6 FBH	140	unsigned long size)
1da177e4	141	{
bbc7b92e	142	unsigned long sidx, eidx;
1da177e4	143	unsigned long i;
bbc7b92e	144
1da177e4 LT	145	/*
	146	* round down end of usable mem, partially free pages are
	147	* considered reserved.
	148	*/
1da177e4	149	BUG_ON(!size);
bbc7b92e	150	BUG_ON(PFN_DOWN(addr + size) > bdata->node_low_pfn);
1da177e4 LT	151
	152	if (addr < bdata->last_success)
	153	bdata->last_success = addr;
	154
	155	/*
	156	* Round up the beginning of the address.
	157	*/
bbc7b92e FBH	158	sidx = PFN_UP(addr) - PFN_DOWN(bdata->node_boot_start);
bbc7b92e FBH	159	eidx = PFN_DOWN(addr + size - bdata->node_boot_start);
1da177e4 LT	160
	161	for (i = sidx; i < eidx; i++) {
	162	if (unlikely(!test_and_clear_bit(i, bdata->node_bootmem_map)))
	163	BUG();
	164	}
	165	}
	166
	167	/*
	168	* We 'merge' subsequent allocations to save space. We might 'lose'
	169	* some fraction of a page if allocations cannot be satisfied due to
	170	* size constraints on boxes where there is physical RAM space
	171	* fragmentation - in these cases (mostly large memory boxes) this
	172	* is not a problem.
	173	*
	174	* On low memory boxes we get it right in 100% of the cases.
	175	*
	176	* alignment has to be a power of 2 value.
	177	*
	178	* NOTE: This function is _not_ reentrant.
	179	*/
267b4801	180	void * __init
1da177e4	181	__alloc_bootmem_core(struct bootmem_data *bdata, unsigned long size,
281dd25c	182	unsigned long align, unsigned long goal, unsigned long limit)
1da177e4 LT	183	{
1da177e4 LT	184	unsigned long offset, remaining_size, areasize, preferred;
bbc7b92e	185	unsigned long i, start = 0, incr, eidx, end_pfn;
1da177e4 LT	186	void *ret;
1da177e4 LT	187
f71bf0ca	188	if (!size) {
1da177e4 LT	189	printk("__alloc_bootmem_core(): zero-sized request\n");
	190	BUG();
	191	}
	192	BUG_ON(align & (align-1));
	193
281dd25c YG	194	if (limit && bdata->node_boot_start >= limit)
	195	return NULL;
	196
7c309a64 CK	197	/* on nodes without memory - bootmem_map is NULL */
	198	if (!bdata->node_bootmem_map)
	199	return NULL;
	200
bbc7b92e FBH	201	end_pfn = bdata->node_low_pfn;
bbc7b92e FBH	202	limit = PFN_DOWN(limit);
281dd25c YG	203	if (limit && end_pfn > limit)
	204	end_pfn = limit;
	205
bbc7b92e	206	eidx = end_pfn - PFN_DOWN(bdata->node_boot_start);
1da177e4	207	offset = 0;
bbc7b92e FBH	208	if (align && (bdata->node_boot_start & (align - 1UL)) != 0)
	209	offset = align - (bdata->node_boot_start & (align - 1UL));
	210	offset = PFN_DOWN(offset);
1da177e4 LT	211
	212	/*
	213	* We try to allocate bootmem pages above 'goal'
	214	* first, then we try to allocate lower pages.
	215	*/
bbc7b92e	216	if (goal && goal >= bdata->node_boot_start && PFN_DOWN(goal) < end_pfn) {
1da177e4 LT	217	preferred = goal - bdata->node_boot_start;
	218
	219	if (bdata->last_success >= preferred)
281dd25c YG	220	if (!limit \|\| (limit && limit > bdata->last_success))
281dd25c YG	221	preferred = bdata->last_success;
1da177e4 LT	222	} else
	223	preferred = 0;
	224
bbc7b92e FBH	225	preferred = PFN_DOWN(ALIGN(preferred, align)) + offset;
bbc7b92e FBH	226	areasize = (size + PAGE_SIZE-1) / PAGE_SIZE;
1da177e4 LT	227	incr = align >> PAGE_SHIFT ? : 1;
	228
	229	restart_scan:
	230	for (i = preferred; i < eidx; i += incr) {
	231	unsigned long j;
	232	i = find_next_zero_bit(bdata->node_bootmem_map, eidx, i);
	233	i = ALIGN(i, incr);
66d43e98 HM	234	if (i >= eidx)
66d43e98 HM	235	break;
1da177e4 LT	236	if (test_bit(i, bdata->node_bootmem_map))
	237	continue;
	238	for (j = i + 1; j < i + areasize; ++j) {
	239	if (j >= eidx)
	240	goto fail_block;
f71bf0ca	241	if (test_bit(j, bdata->node_bootmem_map))
1da177e4 LT	242	goto fail_block;
	243	}
	244	start = i;
	245	goto found;
	246	fail_block:
	247	i = ALIGN(j, incr);
	248	}
	249
	250	if (preferred > offset) {
	251	preferred = offset;
	252	goto restart_scan;
	253	}
	254	return NULL;
	255
	256	found:
bbc7b92e	257	bdata->last_success = PFN_PHYS(start);
1da177e4 LT	258	BUG_ON(start >= eidx);
	259
	260	/*
	261	* Is the next page of the previous allocation-end the start
	262	* of this allocation's buffer? If yes then we can 'merge'
	263	* the previous partial page with this allocation.
	264	*/
	265	if (align < PAGE_SIZE &&
	266	bdata->last_offset && bdata->last_pos+1 == start) {
8c0e33c1	267	offset = ALIGN(bdata->last_offset, align);
1da177e4	268	BUG_ON(offset > PAGE_SIZE);
f71bf0ca	269	remaining_size = PAGE_SIZE - offset;
1da177e4 LT	270	if (size < remaining_size) {
	271	areasize = 0;
	272	/* last_pos unchanged */
f71bf0ca FBH	273	bdata->last_offset = offset + size;
	274	ret = phys_to_virt(bdata->last_pos * PAGE_SIZE +
	275	offset +
	276	bdata->node_boot_start);
1da177e4 LT	277	} else {
1da177e4 LT	278	remaining_size = size - remaining_size;
f71bf0ca FBH	279	areasize = (remaining_size + PAGE_SIZE-1) / PAGE_SIZE;
	280	ret = phys_to_virt(bdata->last_pos * PAGE_SIZE +
	281	offset +
	282	bdata->node_boot_start);
	283	bdata->last_pos = start + areasize - 1;
1da177e4 LT	284	bdata->last_offset = remaining_size;
	285	}
	286	bdata->last_offset &= ~PAGE_MASK;
	287	} else {
	288	bdata->last_pos = start + areasize - 1;
	289	bdata->last_offset = size & ~PAGE_MASK;
	290	ret = phys_to_virt(start * PAGE_SIZE + bdata->node_boot_start);
	291	}
	292
	293	/*
	294	* Reserve the area now:
	295	*/
f71bf0ca	296	for (i = start; i < start + areasize; i++)
1da177e4 LT	297	if (unlikely(test_and_set_bit(i, bdata->node_bootmem_map)))
	298	BUG();
	299	memset(ret, 0, size);
	300	return ret;
	301	}
	302
	303	static unsigned long __init free_all_bootmem_core(pg_data_t *pgdat)
	304	{
	305	struct page *page;
d41dee36	306	unsigned long pfn;
1da177e4 LT	307	bootmem_data_t *bdata = pgdat->bdata;
	308	unsigned long i, count, total = 0;
	309	unsigned long idx;
	310	unsigned long *map;
	311	int gofast = 0;
	312
	313	BUG_ON(!bdata->node_bootmem_map);
	314
	315	count = 0;
	316	/* first extant page of the node */
bbc7b92e FBH	317	pfn = PFN_DOWN(bdata->node_boot_start);
bbc7b92e FBH	318	idx = bdata->node_low_pfn - pfn;
1da177e4 LT	319	map = bdata->node_bootmem_map;
	320	/* Check physaddr is O(LOG2(BITS_PER_LONG)) page aligned */
	321	if (bdata->node_boot_start == 0 \|\|
	322	ffs(bdata->node_boot_start) - PAGE_SHIFT > ffs(BITS_PER_LONG))
	323	gofast = 1;
	324	for (i = 0; i < idx; ) {
	325	unsigned long v = ~map[i / BITS_PER_LONG];
d41dee36	326
1da177e4	327	if (gofast && v == ~0UL) {
a226f6c8	328	int order;
1da177e4	329
d41dee36	330	page = pfn_to_page(pfn);
1da177e4	331	count += BITS_PER_LONG;
1da177e4	332	order = ffs(BITS_PER_LONG) - 1;
a226f6c8	333	__free_pages_bootmem(page, order);
1da177e4 LT	334	i += BITS_PER_LONG;
	335	page += BITS_PER_LONG;
	336	} else if (v) {
	337	unsigned long m;
d41dee36 AW	338
d41dee36 AW	339	page = pfn_to_page(pfn);
1da177e4 LT	340	for (m = 1; m && i < idx; m<<=1, page++, i++) {
	341	if (v & m) {
	342	count++;
a226f6c8	343	__free_pages_bootmem(page, 0);
1da177e4 LT	344	}
	345	}
	346	} else {
f71bf0ca	347	i += BITS_PER_LONG;
1da177e4	348	}
d41dee36	349	pfn += BITS_PER_LONG;
1da177e4 LT	350	}
	351	total += count;
	352
	353	/*
	354	* Now free the allocator bitmap itself, it's not
	355	* needed anymore:
	356	*/
	357	page = virt_to_page(bdata->node_bootmem_map);
	358	count = 0;
bbc7b92e FBH	359	idx = (get_mapsize(bdata) + PAGE_SIZE-1) >> PAGE_SHIFT;
bbc7b92e FBH	360	for (i = 0; i < idx; i++, page++) {
a226f6c8	361	__free_pages_bootmem(page, 0);
bbc7b92e	362	count++;
1da177e4 LT	363	}
	364	total += count;
	365	bdata->node_bootmem_map = NULL;
	366
	367	return total;
	368	}
	369
f71bf0ca	370	unsigned long __init init_bootmem_node(pg_data_t *pgdat, unsigned long freepfn,
bb0923a6	371	unsigned long startpfn, unsigned long endpfn)
1da177e4	372	{
f71bf0ca	373	return init_bootmem_core(pgdat, freepfn, startpfn, endpfn);
1da177e4 LT	374	}
1da177e4 LT	375
f71bf0ca FBH	376	void __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
f71bf0ca FBH	377	unsigned long size)
1da177e4 LT	378	{
	379	reserve_bootmem_core(pgdat->bdata, physaddr, size);
	380	}
	381
f71bf0ca FBH	382	void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
f71bf0ca FBH	383	unsigned long size)
1da177e4 LT	384	{
	385	free_bootmem_core(pgdat->bdata, physaddr, size);
	386	}
	387
f71bf0ca	388	unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
1da177e4	389	{
f71bf0ca	390	return free_all_bootmem_core(pgdat);
1da177e4 LT	391	}
1da177e4 LT	392
f71bf0ca	393	unsigned long __init init_bootmem(unsigned long start, unsigned long pages)
1da177e4 LT	394	{
	395	max_low_pfn = pages;
	396	min_low_pfn = start;
f71bf0ca	397	return init_bootmem_core(NODE_DATA(0), start, 0, pages);
1da177e4 LT	398	}
	399
	400	#ifndef CONFIG_HAVE_ARCH_BOOTMEM_NODE
f71bf0ca	401	void __init reserve_bootmem(unsigned long addr, unsigned long size)
1da177e4 LT	402	{
	403	reserve_bootmem_core(NODE_DATA(0)->bdata, addr, size);
	404	}
	405	#endif /* !CONFIG_HAVE_ARCH_BOOTMEM_NODE */
	406
f71bf0ca	407	void __init free_bootmem(unsigned long addr, unsigned long size)
1da177e4 LT	408	{
	409	free_bootmem_core(NODE_DATA(0)->bdata, addr, size);
	410	}
	411
f71bf0ca	412	unsigned long __init free_all_bootmem(void)
1da177e4	413	{
f71bf0ca	414	return free_all_bootmem_core(NODE_DATA(0));
1da177e4 LT	415	}
1da177e4 LT	416
bb0923a6 FBH	417	void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align,
bb0923a6 FBH	418	unsigned long goal)
1da177e4	419	{
679bc9fb	420	bootmem_data_t *bdata;
1da177e4 LT	421	void *ptr;
1da177e4 LT	422
f71bf0ca FBH	423	list_for_each_entry(bdata, &bdata_list, list) {
	424	ptr = __alloc_bootmem_core(bdata, size, align, goal, 0);
	425	if (ptr)
	426	return ptr;
	427	}
a8062231 AK	428	return NULL;
a8062231 AK	429	}
1da177e4	430
bb0923a6 FBH	431	void * __init __alloc_bootmem(unsigned long size, unsigned long align,
bb0923a6 FBH	432	unsigned long goal)
a8062231 AK	433	{
a8062231 AK	434	void *mem = __alloc_bootmem_nopanic(size,align,goal);
f71bf0ca	435
a8062231 AK	436	if (mem)
a8062231 AK	437	return mem;
1da177e4 LT	438	/*
	439	* Whoops, we cannot satisfy the allocation request.
	440	*/
	441	printk(KERN_ALERT "bootmem alloc of %lu bytes failed!\n", size);
	442	panic("Out of memory");
	443	return NULL;
	444	}
	445
281dd25c	446
bb0923a6 FBH	447	void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
bb0923a6 FBH	448	unsigned long align, unsigned long goal)
1da177e4 LT	449	{
	450	void *ptr;
	451
008857c1	452	ptr = __alloc_bootmem_core(pgdat->bdata, size, align, goal, 0);
1da177e4	453	if (ptr)
f71bf0ca	454	return ptr;
1da177e4	455
008857c1	456	return __alloc_bootmem(size, align, goal);
1da177e4 LT	457	}
1da177e4 LT	458
dfd54cbc HC	459	#ifndef ARCH_LOW_ADDRESS_LIMIT
	460	#define ARCH_LOW_ADDRESS_LIMIT 0xffffffffUL
	461	#endif
008857c1	462
bb0923a6 FBH	463	void * __init __alloc_bootmem_low(unsigned long size, unsigned long align,
bb0923a6 FBH	464	unsigned long goal)
008857c1	465	{
679bc9fb	466	bootmem_data_t *bdata;
008857c1 RT	467	void *ptr;
008857c1 RT	468
f71bf0ca	469	list_for_each_entry(bdata, &bdata_list, list) {
dfd54cbc HC	470	ptr = __alloc_bootmem_core(bdata, size, align, goal,
dfd54cbc HC	471	ARCH_LOW_ADDRESS_LIMIT);
f71bf0ca FBH	472	if (ptr)
	473	return ptr;
	474	}
008857c1 RT	475
	476	/*
	477	* Whoops, we cannot satisfy the allocation request.
	478	*/
	479	printk(KERN_ALERT "low bootmem alloc of %lu bytes failed!\n", size);
	480	panic("Out of low memory");
	481	return NULL;
	482	}
	483
	484	void * __init __alloc_bootmem_low_node(pg_data_t *pgdat, unsigned long size,
	485	unsigned long align, unsigned long goal)
	486	{
dfd54cbc HC	487	return __alloc_bootmem_core(pgdat->bdata, size, align, goal,
dfd54cbc HC	488	ARCH_LOW_ADDRESS_LIMIT);
008857c1	489	}