linux/mm/bootmem.c
Max Filippov 10d73e655c mm: bootmem: fix free_all_bootmem_core() with odd bitmap alignment
Currently free_all_bootmem_core ignores that node_min_pfn may be not
multiple of BITS_PER_LONG.  Eg commit 6dccdcbe2c ("mm: bootmem: fix
checking the bitmap when finally freeing bootmem") shifts vec by lower
bits of start instead of lower bits of idx.  Also

  if (IS_ALIGNED(start, BITS_PER_LONG) && vec == ~0UL)

assumes that vec bit 0 corresponds to start pfn, which is only true when
node_min_pfn is a multiple of BITS_PER_LONG.  Also loop in the else
clause can double-free pages (e.g.  with node_min_pfn == start == 1,
map[0] == ~0 on 32-bit machine page 32 will be double-freed).

This bug causes the following message during xtensa kernel boot:

  bootmem::free_all_bootmem_core nid=0 start=1 end=8000
  BUG: Bad page state in process swapper  pfn:00001
  page:d04bd020 count:0 mapcount:-127 mapping:  (null) index:0x2
  page flags: 0x0()
  Call Trace:
    bad_page+0x8c/0x9c
    free_pages_prepare+0x5e/0x88
    free_hot_cold_page+0xc/0xa0
    __free_pages+0x24/0x38
    __free_pages_bootmem+0x54/0x56
    free_all_bootmem_core$part$11+0xeb/0x138
    free_all_bootmem+0x46/0x58
    mem_init+0x25/0xa4
    start_kernel+0x11e/0x25c
    should_never_return+0x0/0x3be7

The fix is the following:
 - always align vec so that its bit 0 corresponds to start
 - provide BITS_PER_LONG bits in vec, if those bits are available in the
   map
 - don't free pages past next start position in the else clause.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Prasad Koya <prasad.koya@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-11 14:54:55 -08:00

860 lines
21 KiB
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 = {
.bdata = &bootmem_node_data[0]
};
EXPORT_SYMBOL(contig_page_data);
#endif
unsigned long max_low_pfn;
unsigned long min_low_pfn;
unsigned long max_pfn;
bootmem_data_t bootmem_node_data[MAX_NUMNODES] __initdata;
static struct list_head bdata_list __initdata = LIST_HEAD_INIT(bdata_list);
static int bootmem_debug;
static int __init bootmem_debug_setup(char *buf)
{
bootmem_debug = 1;
return 0;
}
early_param("bootmem_debug", bootmem_debug_setup);
#define bdebug(fmt, args...) ({ \
if (unlikely(bootmem_debug)) \
printk(KERN_INFO \
"bootmem::%s " fmt, \
__func__, ## args); \
})
static unsigned long __init bootmap_bytes(unsigned long pages)
{
unsigned long bytes = DIV_ROUND_UP(pages, 8);
return ALIGN(bytes, sizeof(long));
}
/**
* bootmem_bootmap_pages - calculate bitmap size in pages
* @pages: number of pages the bitmap has to represent
*/
unsigned long __init bootmem_bootmap_pages(unsigned long pages)
{
unsigned long bytes = bootmap_bytes(pages);
return PAGE_ALIGN(bytes) >> PAGE_SHIFT;
}
/*
* link bdata in order
*/
static void __init link_bootmem(bootmem_data_t *bdata)
{
bootmem_data_t *ent;
list_for_each_entry(ent, &bdata_list, list) {
if (bdata->node_min_pfn < ent->node_min_pfn) {
list_add_tail(&bdata->list, &ent->list);
return;
}
}
list_add_tail(&bdata->list, &bdata_list);
}
/*
* Called once to set up the allocator itself.
*/
static unsigned long __init init_bootmem_core(bootmem_data_t *bdata,
unsigned long mapstart, unsigned long start, unsigned long end)
{
unsigned long mapsize;
mminit_validate_memmodel_limits(&start, &end);
bdata->node_bootmem_map = phys_to_virt(PFN_PHYS(mapstart));
bdata->node_min_pfn = start;
bdata->node_low_pfn = end;
link_bootmem(bdata);
/*
* Initially all pages are reserved - setup_arch() has to
* register free RAM areas explicitly.
*/
mapsize = bootmap_bytes(end - start);
memset(bdata->node_bootmem_map, 0xff, mapsize);
bdebug("nid=%td start=%lx map=%lx end=%lx mapsize=%lx\n",
bdata - bootmem_node_data, start, mapstart, end, mapsize);
return mapsize;
}
/**
* init_bootmem_node - register a node as boot memory
* @pgdat: node to register
* @freepfn: pfn where the bitmap for this node is to be placed
* @startpfn: first pfn on the node
* @endpfn: first pfn after the node
*
* Returns the number of bytes needed to hold the bitmap for this node.
*/
unsigned long __init init_bootmem_node(pg_data_t *pgdat, unsigned long freepfn,
unsigned long startpfn, unsigned long endpfn)
{
return init_bootmem_core(pgdat->bdata, freepfn, startpfn, endpfn);
}
/**
* init_bootmem - register boot memory
* @start: pfn where the bitmap is to be placed
* @pages: number of available physical pages
*
* Returns the number of bytes needed to hold the bitmap.
*/
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)->bdata, start, 0, pages);
}
/*
* free_bootmem_late - free bootmem pages directly to page allocator
* @addr: starting physical 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 physaddr, unsigned long size)
{
unsigned long cursor, end;
kmemleak_free_part(__va(physaddr), size);
cursor = PFN_UP(physaddr);
end = PFN_DOWN(physaddr + size);
for (; cursor < end; cursor++) {
__free_pages_bootmem(pfn_to_page(cursor), 0);
totalram_pages++;
}
}
static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)
{
struct page *page;
unsigned long start, end, pages, count = 0;
if (!bdata->node_bootmem_map)
return 0;
start = bdata->node_min_pfn;
end = bdata->node_low_pfn;
bdebug("nid=%td start=%lx end=%lx\n",
bdata - bootmem_node_data, start, end);
while (start < end) {
unsigned long *map, idx, vec;
unsigned shift;
map = bdata->node_bootmem_map;
idx = start - bdata->node_min_pfn;
shift = idx & (BITS_PER_LONG - 1);
/*
* vec holds at most BITS_PER_LONG map bits,
* bit 0 corresponds to start.
*/
vec = ~map[idx / BITS_PER_LONG];
if (shift) {
vec >>= shift;
if (end - start >= BITS_PER_LONG)
vec |= ~map[idx / BITS_PER_LONG + 1] <<
(BITS_PER_LONG - shift);
}
/*
* If we have a properly aligned and fully unreserved
* BITS_PER_LONG block of pages in front of us, free
* it in one go.
*/
if (IS_ALIGNED(start, BITS_PER_LONG) && vec == ~0UL) {
int order = ilog2(BITS_PER_LONG);
__free_pages_bootmem(pfn_to_page(start), order);
count += BITS_PER_LONG;
start += BITS_PER_LONG;
} else {
unsigned long cur = start;
start = ALIGN(start + 1, BITS_PER_LONG);
while (vec && cur != start) {
if (vec & 1) {
page = pfn_to_page(cur);
__free_pages_bootmem(page, 0);
count++;
}
vec >>= 1;
++cur;
}
}
}
page = virt_to_page(bdata->node_bootmem_map);
pages = bdata->node_low_pfn - bdata->node_min_pfn;
pages = bootmem_bootmap_pages(pages);
count += pages;
while (pages--)
__free_pages_bootmem(page++, 0);
bdebug("nid=%td released=%lx\n", bdata - bootmem_node_data, count);
return count;
}
static void reset_node_lowmem_managed_pages(pg_data_t *pgdat)
{
struct zone *z;
/*
* In free_area_init_core(), highmem zone's managed_pages is set to
* present_pages, and bootmem allocator doesn't allocate from highmem
* zones. So there's no need to recalculate managed_pages because all
* highmem pages will be managed by the buddy system. Here highmem
* zone also includes highmem movable zone.
*/
for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
if (!is_highmem(z))
z->managed_pages = 0;
}
/**
* 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);
reset_node_lowmem_managed_pages(pgdat);
return free_all_bootmem_core(pgdat->bdata);
}
/**
* free_all_bootmem - release free pages to the buddy allocator
*
* Returns the number of pages actually released.
*/
unsigned long __init free_all_bootmem(void)
{
unsigned long total_pages = 0;
bootmem_data_t *bdata;
struct pglist_data *pgdat;
for_each_online_pgdat(pgdat)
reset_node_lowmem_managed_pages(pgdat);
list_for_each_entry(bdata, &bdata_list, list)
total_pages += free_all_bootmem_core(bdata);
return total_pages;
}
static void __init __free(bootmem_data_t *bdata,
unsigned long sidx, unsigned long eidx)
{
unsigned long idx;
bdebug("nid=%td start=%lx end=%lx\n", bdata - bootmem_node_data,
sidx + bdata->node_min_pfn,
eidx + bdata->node_min_pfn);
if (bdata->hint_idx > sidx)
bdata->hint_idx = sidx;
for (idx = sidx; idx < eidx; idx++)
if (!test_and_clear_bit(idx, bdata->node_bootmem_map))
BUG();
}
static int __init __reserve(bootmem_data_t *bdata, unsigned long sidx,
unsigned long eidx, int flags)
{
unsigned long idx;
int exclusive = flags & BOOTMEM_EXCLUSIVE;
bdebug("nid=%td start=%lx end=%lx flags=%x\n",
bdata - bootmem_node_data,
sidx + bdata->node_min_pfn,
eidx + bdata->node_min_pfn,
flags);
for (idx = sidx; idx < eidx; idx++)
if (test_and_set_bit(idx, bdata->node_bootmem_map)) {
if (exclusive) {
__free(bdata, sidx, idx);
return -EBUSY;
}
bdebug("silent double reserve of PFN %lx\n",
idx + bdata->node_min_pfn);
}
return 0;
}
static int __init mark_bootmem_node(bootmem_data_t *bdata,
unsigned long start, unsigned long end,
int reserve, int flags)
{
unsigned long sidx, eidx;
bdebug("nid=%td start=%lx end=%lx reserve=%d flags=%x\n",
bdata - bootmem_node_data, start, end, reserve, flags);
BUG_ON(start < bdata->node_min_pfn);
BUG_ON(end > bdata->node_low_pfn);
sidx = start - bdata->node_min_pfn;
eidx = end - bdata->node_min_pfn;
if (reserve)
return __reserve(bdata, sidx, eidx, flags);
else
__free(bdata, sidx, eidx);
return 0;
}
static int __init mark_bootmem(unsigned long start, unsigned long end,
int reserve, int flags)
{
unsigned long pos;
bootmem_data_t *bdata;
pos = start;
list_for_each_entry(bdata, &bdata_list, list) {
int err;
unsigned long max;
if (pos < bdata->node_min_pfn ||
pos >= bdata->node_low_pfn) {
BUG_ON(pos != start);
continue;
}
max = min(bdata->node_low_pfn, end);
err = mark_bootmem_node(bdata, pos, max, reserve, flags);
if (reserve && err) {
mark_bootmem(start, pos, 0, 0);
return err;
}
if (max == end)
return 0;
pos = bdata->node_low_pfn;
}
BUG();
}
/**
* 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)
{
unsigned long start, end;
kmemleak_free_part(__va(physaddr), size);
start = PFN_UP(physaddr);
end = PFN_DOWN(physaddr + size);
mark_bootmem_node(pgdat->bdata, start, end, 0, 0);
}
/**
* free_bootmem - mark a page range as usable
* @addr: starting physical 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 physaddr, unsigned long size)
{
unsigned long start, end;
kmemleak_free_part(__va(physaddr), size);
start = PFN_UP(physaddr);
end = PFN_DOWN(physaddr + size);
mark_bootmem(start, end, 0, 0);
}
/**
* reserve_bootmem_node - mark a page range as reserved
* @pgdat: node the range resides on
* @physaddr: starting address of the range
* @size: size of the range in bytes
* @flags: reservation flags (see linux/bootmem.h)
*
* Partial pages will be reserved.
*
* The range must reside completely on the specified node.
*/
int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
unsigned long size, int flags)
{
unsigned long start, end;
start = PFN_DOWN(physaddr);
end = PFN_UP(physaddr + size);
return mark_bootmem_node(pgdat->bdata, start, end, 1, flags);
}
/**
* reserve_bootmem - mark a page range as reserved
* @addr: starting address of the range
* @size: size of the range in bytes
* @flags: reservation flags (see linux/bootmem.h)
*
* Partial pages will be reserved.
*
* The range must be contiguous but may span node boundaries.
*/
int __init reserve_bootmem(unsigned long addr, unsigned long size,
int flags)
{
unsigned long start, end;
start = PFN_DOWN(addr);
end = PFN_UP(addr + size);
return mark_bootmem(start, end, 1, flags);
}
static unsigned long __init align_idx(struct bootmem_data *bdata,
unsigned long idx, unsigned long step)
{
unsigned long base = bdata->node_min_pfn;
/*
* Align the index with respect to the node start so that the
* combination of both satisfies the requested alignment.
*/
return ALIGN(base + idx, step) - base;
}
static unsigned long __init align_off(struct bootmem_data *bdata,
unsigned long off, unsigned long align)
{
unsigned long base = PFN_PHYS(bdata->node_min_pfn);
/* Same as align_idx for byte offsets */
return ALIGN(base + off, align) - base;
}
static void * __init alloc_bootmem_bdata(struct bootmem_data *bdata,
unsigned long size, unsigned long align,
unsigned long goal, unsigned long limit)
{
unsigned long fallback = 0;
unsigned long min, max, start, sidx, midx, step;
bdebug("nid=%td size=%lx [%lu pages] align=%lx goal=%lx limit=%lx\n",
bdata - bootmem_node_data, size, PAGE_ALIGN(size) >> PAGE_SHIFT,
align, goal, limit);
BUG_ON(!size);
BUG_ON(align & (align - 1));
BUG_ON(limit && goal + size > limit);
if (!bdata->node_bootmem_map)
return NULL;
min = bdata->node_min_pfn;
max = bdata->node_low_pfn;
goal >>= PAGE_SHIFT;
limit >>= PAGE_SHIFT;
if (limit && max > limit)
max = limit;
if (max <= min)
return NULL;
step = max(align >> PAGE_SHIFT, 1UL);
if (goal && min < goal && goal < max)
start = ALIGN(goal, step);
else
start = ALIGN(min, step);
sidx = start - bdata->node_min_pfn;
midx = max - bdata->node_min_pfn;
if (bdata->hint_idx > sidx) {
/*
* Handle the valid case of sidx being zero and still
* catch the fallback below.
*/
fallback = sidx + 1;
sidx = align_idx(bdata, bdata->hint_idx, step);
}
while (1) {
int merge;
void *region;
unsigned long eidx, i, start_off, end_off;
find_block:
sidx = find_next_zero_bit(bdata->node_bootmem_map, midx, sidx);
sidx = align_idx(bdata, sidx, step);
eidx = sidx + PFN_UP(size);
if (sidx >= midx || eidx > midx)
break;
for (i = sidx; i < eidx; i++)
if (test_bit(i, bdata->node_bootmem_map)) {
sidx = align_idx(bdata, i, step);
if (sidx == i)
sidx += step;
goto find_block;
}
if (bdata->last_end_off & (PAGE_SIZE - 1) &&
PFN_DOWN(bdata->last_end_off) + 1 == sidx)
start_off = align_off(bdata, bdata->last_end_off, align);
else
start_off = PFN_PHYS(sidx);
merge = PFN_DOWN(start_off) < sidx;
end_off = start_off + size;
bdata->last_end_off = end_off;
bdata->hint_idx = PFN_UP(end_off);
/*
* Reserve the area now:
*/
if (__reserve(bdata, PFN_DOWN(start_off) + merge,
PFN_UP(end_off), BOOTMEM_EXCLUSIVE))
BUG();
region = phys_to_virt(PFN_PHYS(bdata->node_min_pfn) +
start_off);
memset(region, 0, size);
/*
* The min_count is set to 0 so that bootmem allocated blocks
* are never reported as leaks.
*/
kmemleak_alloc(region, size, 0, 0);
return region;
}
if (fallback) {
sidx = align_idx(bdata, fallback - 1, step);
fallback = 0;
goto find_block;
}
return NULL;
}
static void * __init alloc_bootmem_core(unsigned long size,
unsigned long align,
unsigned long goal,
unsigned long limit)
{
bootmem_data_t *bdata;
void *region;
if (WARN_ON_ONCE(slab_is_available()))
return kzalloc(size, GFP_NOWAIT);
list_for_each_entry(bdata, &bdata_list, list) {
if (goal && bdata->node_low_pfn <= PFN_DOWN(goal))
continue;
if (limit && bdata->node_min_pfn >= PFN_DOWN(limit))
break;
region = alloc_bootmem_bdata(bdata, size, align, goal, limit);
if (region)
return region;
}
return NULL;
}
static void * __init ___alloc_bootmem_nopanic(unsigned long size,
unsigned long align,
unsigned long goal,
unsigned long limit)
{
void *ptr;
restart:
ptr = alloc_bootmem_core(size, align, goal, limit);
if (ptr)
return ptr;
if (goal) {
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 = 0;
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 = 0;
return ___alloc_bootmem(size, align, goal, limit);
}
void * __init ___alloc_bootmem_node_nopanic(pg_data_t *pgdat,
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);
again:
/* do not panic in alloc_bootmem_bdata() */
if (limit && goal + size > limit)
limit = 0;
ptr = alloc_bootmem_bdata(pgdat->bdata, size, align, goal, limit);
if (ptr)
return ptr;
ptr = alloc_bootmem_core(size, align, goal, limit);
if (ptr)
return ptr;
if (goal) {
goal = 0;
goto again;
}
return NULL;
}
void * __init __alloc_bootmem_node_nopanic(pg_data_t *pgdat, unsigned long size,
unsigned long align, unsigned long goal)
{
if (WARN_ON_ONCE(slab_is_available()))
return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
return ___alloc_bootmem_node_nopanic(pgdat, size, align, goal, 0);
}
void * __init ___alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
unsigned long align, unsigned long goal,
unsigned long limit)
{
void *ptr;
ptr = ___alloc_bootmem_node_nopanic(pgdat, size, align, goal, 0);
if (ptr)
return ptr;
printk(KERN_ALERT "bootmem alloc of %lu bytes failed!\n", size);
panic("Out of memory");
return NULL;
}
/**
* __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)
{
if (WARN_ON_ONCE(slab_is_available()))
return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
return ___alloc_bootmem_node(pgdat, size, align, goal, 0);
}
void * __init __alloc_bootmem_node_high(pg_data_t *pgdat, unsigned long size,
unsigned long align, unsigned long goal)
{
#ifdef MAX_DMA32_PFN
unsigned long end_pfn;
if (WARN_ON_ONCE(slab_is_available()))
return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
/* update goal according ...MAX_DMA32_PFN */
end_pfn = pgdat->node_start_pfn + pgdat->node_spanned_pages;
if (end_pfn > MAX_DMA32_PFN + (128 >> (20 - PAGE_SHIFT)) &&
(goal >> PAGE_SHIFT) < MAX_DMA32_PFN) {
void *ptr;
unsigned long new_goal;
new_goal = MAX_DMA32_PFN << PAGE_SHIFT;
ptr = alloc_bootmem_bdata(pgdat->bdata, size, align,
new_goal, 0);
if (ptr)
return ptr;
}
#endif
return __alloc_bootmem_node(pgdat, 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)
{
if (WARN_ON_ONCE(slab_is_available()))
return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
return ___alloc_bootmem_node(pgdat, size, align,
goal, ARCH_LOW_ADDRESS_LIMIT);
}