/*
* 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/bootmem.h>
#include <linux/module.h>
#include <asm/bug.h>
#include <asm/io.h>
#include <asm/processor.h>
#include "internal.h"
unsigned long max_low_pfn;
unsigned long min_low_pfn;
unsigned long max_pfn;
#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
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, \
__FUNCTION__, ## args); \
})
static unsigned long __init bootmap_bytes(unsigned long pages)
{
unsigned long bytes = (pages + 7) / 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)
{
struct list_head *iter;
list_for_each(iter, &bdata_list) {
bootmem_data_t *ent;
ent = list_entry(iter, bootmem_data_t, list);
if (bdata->node_boot_start < ent->node_boot_start)
break;
}
list_add_tail(&bdata->list, iter);
}
/*
* 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_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 = 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);
}
static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)
{
int aligned;
struct page *page;
unsigned long start, end, pages, count = 0;
if (!bdata->node_bootmem_map)
return 0;
start = PFN_DOWN(bdata->node_boot_start);
end = bdata->node_low_pfn;
/*
* If the start is aligned to the machines wordsize, we might
* be able to free pages in bulks of that order.
*/
aligned = !(start & (BITS_PER_LONG - 1));
bdebug("nid=%td start=%lx end=%lx aligned=%d\n",
bdata - bootmem_node_data, start, end, aligned);
while (start < end) {
unsigned long *map, idx, vec;
map = bdata->node_bootmem_map;
idx = start - PFN_DOWN(bdata->node_boot_start);
vec = ~map[idx / BITS_PER_LONG];
if (aligned && vec == ~0UL && start + BITS_PER_LONG < end) {
int order = ilog2(BITS_PER_LONG);
__free_pages_bootmem(pfn_to_page(start), order);
count += BITS_PER_LONG;
} else {
unsigned long off = 0;
while (vec && off < BITS_PER_LONG) {
if (vec & 1) {
page = pfn_to_page(start + off);
__free_pages_bootmem(page, 0);
count++;
}
vec >>= 1;
off++;
}
}
start += BITS_PER_LONG;
}
page = virt_to_page(bdata->node_bootmem_map);
pages = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);
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;
}
/**
* 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);
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)
{
return free_all_bootmem_core(NODE_DATA(0)->bdata);
}
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 + PFN_DOWN(bdata->node_boot_start),
eidx + PFN_DOWN(bdata->node_boot_start));
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 + PFN_DOWN(bdata->node_boot_start),
eidx + PFN_DOWN(bdata->node_boot_start),
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 + PFN_DOWN(bdata->node_boot_start));
}
return 0;
}
static void __init free_bootmem_core(bootmem_data_t *bdata, unsigned long addr,
unsigned long size)
{
unsigned long sidx, eidx;
unsigned long i;
BUG_ON(!size);
/* out range */
if (addr + size < bdata->node_boot_start ||
PFN_DOWN(addr) > bdata->node_low_pfn)
return;
/*
* round down end of usable mem, partially free pages are
* considered reserved.
*/
if (addr >= bdata->node_boot_start &&
PFN_DOWN(addr - bdata->node_boot_start) < bdata->hint_idx)
bdata->hint_idx = PFN_DOWN(addr - bdata->node_boot_start);
/*
* Round up to index to the range.
*/
if (PFN_UP(addr) > PFN_DOWN(bdata->node_boot_start))
sidx = PFN_UP(addr) - PFN_DOWN(bdata->node_boot_start);
else
sidx = 0;
eidx = PFN_DOWN(addr + size - bdata->node_boot_start);
if (eidx > bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start))
eidx = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);
__free(bdata, sidx, eidx);
}
/**
* 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.
*
* Only physical pages that actually reside on @pgdat are marked.
*/
void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
unsigned long size)
{
free_bootmem_core(pgdat->bdata, 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.
*
* All physical pages within the range are marked, no matter what
* node they reside on.
*/
void __init free_bootmem(unsigned long addr, unsigned long size)
{
bootmem_data_t *bdata;
list_for_each_entry(bdata, &bdata_list, list)
free_bootmem_core(bdata, addr, size);
}
/*
* 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 int __init can_reserve_bootmem_core(bootmem_data_t *bdata,
unsigned long addr, unsigned long size, int flags)
{
unsigned long sidx, eidx;
unsigned long i;
BUG_ON(!size);
/* out of range, don't hold other */
if (addr + size < bdata->node_boot_start ||
PFN_DOWN(addr) > bdata->node_low_pfn)
return 0;
/*
* Round up to index to the range.
*/
if (addr > bdata->node_boot_start)
sidx= PFN_DOWN(addr - bdata->node_boot_start);
else
sidx = 0;
eidx = PFN_UP(addr + size - bdata->node_boot_start);
if (eidx > bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start))
eidx = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);
for (i = sidx; i < eidx; i++) {
if (test_bit(i, bdata->node_bootmem_map)) {
if (flags & BOOTMEM_EXCLUSIVE)
return -EBUSY;
}
}
return 0;
}
static void __init reserve_bootmem_core(bootmem_data_t *bdata,
unsigned long addr, unsigned long size, int flags)
{
unsigned long sidx, eidx;
unsigned long i;
BUG_ON(!size);
/* out of range */
if (addr + size < bdata->node_boot_start ||
PFN_DOWN(addr) > bdata->node_low_pfn)
return;
/*
* Round up to index to the range.
*/
if (addr > bdata->node_boot_start)
sidx= PFN_DOWN(addr - bdata->node_boot_start);
else
sidx = 0;
eidx = PFN_UP(addr + size - bdata->node_boot_start);
if (eidx > bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start))
eidx = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);
return __reserve(bdata, sidx, eidx, flags);
}
/**
* 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.
*
* Only physical pages that actually reside on @pgdat are marked.
*/
int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
unsigned long size, int flags)
{
int ret;
ret = can_reserve_bootmem_core(pgdat->bdata, physaddr, size, flags);
if (ret < 0)
return -ENOMEM;
reserve_bootmem_core(pgdat->bdata, physaddr, size, flags);
return 0;
}
#ifndef CONFIG_HAVE_ARCH_BOOTMEM_NODE
/**
* reserve_bootmem - mark a page range as usable
* @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.
*
* All physical pages within the range are marked, no matter what
* node they reside on.
*/
int __init reserve_bootmem(unsigned long addr, unsigned long size,
int flags)
{
bootmem_data_t *bdata;
int ret;
list_for_each_entry(bdata, &bdata_list, list) {
ret = can_reserve_bootmem_core(bdata, addr, size, flags);
if (ret < 0)
return ret;
}
list_for_each_entry(bdata, &bdata_list, list)
reserve_bootmem_core(bdata, addr, size, flags);
return 0;
}
#endif /* !CONFIG_HAVE_ARCH_BOOTMEM_NODE */
static void * __init alloc_bootmem_core(struct bootmem_data *bdata,
unsigned long size, unsigned long align,
unsigned long goal, unsigned long limit)
{
unsigned long min, max, start, sidx, midx, step;
BUG_ON(!size);
BUG_ON(align & (align - 1));
BUG_ON(limit && goal + size > limit);
if (!bdata->node_bootmem_map)
return NULL;
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);
min = PFN_DOWN(bdata->node_boot_start);
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 - PFN_DOWN(bdata->node_boot_start);
midx = max - PFN_DOWN(bdata->node_boot_start);
if (bdata->hint_idx > sidx) {
/* Make sure we retry on failure */
goal = 1;
sidx = ALIGN(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(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(i, step);
if (sidx == i)
sidx += step;
goto find_block;
}
if (bdata->last_end_off &&
PFN_DOWN(bdata->last_end_off) + 1 == sidx)
start_off = ALIGN(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(bdata->node_boot_start + start_off);
memset(region, 0, size);
return region;
}
if (goal) {
goal = 0;
sidx = 0;
goto find_block;
}
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)
{
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;
}
/**
* __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)
{
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;
}
/**
* __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;
ptr = alloc_bootmem_core(pgdat->bdata, size, align, goal, 0);
if (ptr)
return ptr;
return __alloc_bootmem(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)
{
void *ptr;
unsigned long limit, goal, start_nr, end_nr, pfn;
struct pglist_data *pgdat;
pfn = section_nr_to_pfn(section_nr);
goal = PFN_PHYS(pfn);
limit = PFN_PHYS(section_nr_to_pfn(section_nr + 1)) - 1;
pgdat = NODE_DATA(early_pfn_to_nid(pfn));
ptr = alloc_bootmem_core(pgdat->bdata, size, SMP_CACHE_BYTES, goal,
limit);
if (!ptr)
return NULL;
start_nr = pfn_to_section_nr(PFN_DOWN(__pa(ptr)));
end_nr = pfn_to_section_nr(PFN_DOWN(__pa(ptr) + size));
if (start_nr != section_nr || end_nr != section_nr) {
printk(KERN_WARNING "alloc_bootmem failed on section %ld.\n",
section_nr);
free_bootmem_core(pgdat->bdata, __pa(ptr), size);
ptr = NULL;
}
return ptr;
}
#endif
void * __init __alloc_bootmem_node_nopanic(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_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)
{
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;
}
/**
* __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)
{
return alloc_bootmem_core(pgdat->bdata, size, align, goal,
ARCH_LOW_ADDRESS_LIMIT);
}